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Individual Fairness for Graph Neural Networks: A Ranking based Approach

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

1Yaochen Zhu 1Yinhan He 2Jing Ma 1 Mengxuan Hu 1Sheng Li 1Jundong Li

1University of Virginia

2Case Western Reserve University

Causal Inference with Latent Variables:

Recent Advances & Future Prospectives

1

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About This Tutorial

  • Background and Causal Inference Basics 2:00 – 2:45
  • Latent Confounding Analysis 2:50 – 3:20
  • Latent Mediation Analysis 3:20 – 3:35
  • Counterfactual Analysis 3:35 – 3:55
  • Generalization to Graphs 4:30 – 4:50
  • Challenges & Future Directions 4:50 – 5:00

2

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Schedule
  • Website
  • Survey Paper

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Outline

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Background and Causal Inference Basics

Counterfactual Analysis

Challenges & Future Directions

Latent Confounding Analysis

Generalization to Graphs

Latent Mediation Analysis

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Overview of Causal Inference

  • Causality studies “cause and effect” relations

4

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Overview of Causal Inference

  • Causality studies “cause and effect” relations
  • It has been widely discussed in many scientific fields

5

such as:

Medicine

Politics

Economy

Clinical trial

Geo-political influence

Econ-factors

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Overview of Causal Inference

  • Causality studies “cause and effect” relations
  • It also closely related to our lives

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Overview of Causal Inference

  • Causality studies “cause and effect” relations
  • It also closely related to our lives

7

attend this tutorial (T)

research productivity (Y)

For example, you may wonder about the following:

Jundong

Yaochen

* You

influence

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Overview of Causal Inference

  • Causality studies “cause and effect” relations
  • It also closely related to our lives

8

attend this tutorial (T)

research productivity (Y)

Jundong

Yaochen

Hopefully, the causal effect of T on Y is positive

influence

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

For example, you may wonder about the following:

* You

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Causal Inference Tasks

  • Treatment Effect Estimation

9

Estimate the causal effect of a treatment variable T on an outcome Y

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Causal Inference Tasks

  • Treatment Effect Estimation

10

Estimate the causal effect of a treatment variable T on an outcome Y

  • Average Treatment Effect (ATE)

Jundong

Yaochen

attending this tutorial (T = 1)

ignore this tutorial (T = 0)

compare

with the same group

average research productivity

average research productivity

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Causal Inference Tasks

  • Treatment Effect Estimation

11

Jundong

Yaochen

attending this tutorial (T = 1)

ignore this tutorial (T = 0)

compare

X = Ph.D. student

X = Professors

X = Area Chair

with the same sub-group

Estimate the causal effect of a treatment variable T on an outcome Y

average research productivity

average research productivity

X = Ph.D. student

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Conditional Average Treatment Effect (CATE)

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Causal Inference Tasks

  • Causal Mediation Analysis (CMA)

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The causal effect of a treatment variable T on an outcome Y

mediated via some other variables M

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Causal Inference Tasks

  • Causal Mediation Analysis (CMA)

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The causal effect of a treatment variable T on an outcome Y

mediated via some other variables M

attend this tutorial (T)

research productivity (Y)

Jundong

Yaochen

M1 = Jundong’s part

M2 = Yaochen’s part

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Causal Inference Tasks

  • Causal Mediation Analysis (CMA)

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The causal effect of a treatment variable T on an outcome Y

mediated via some other variables M

attend this tutorial (T)

research productivity (Y)

Jundong

Yaochen

M1 = Jundong’s part

M2 = Yaochen’s part

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

CMA considers fine-grained causal effect along specific causal chains

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Causal Inference Tasks

  • Counterfactual Analysis

15

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The effects of treatment T on outcome Y had X been x’

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Causal Inference Tasks

  • Counterfactual Analysis

16

Jundong

Yaochen

attended this tutorial

What if I had not attended this tutorial?

(For T=1, what Y would be had T been 0)

  • Average Treatment Effect on the Treated (ATT)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The effects of treatment T on outcome Y had X been x’

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Causal Inference Tasks

  • Counterfactual Analysis

17

Jundong

Yaochen

attended this tutorial

What if I had not attended this tutorial?

(For T=1, what Y would be had T been 0)

Similarly, we can study more fine-grained counterfactuals

  • Average Treatment Effect on the Treated (ATT)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The effects of treatment T on outcome Y had X been x’

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Causal Inference Tasks

  • Counterfactual Analysis

18

Jundong

Yaochen

M1 = Jundong’s part

M2 = Yaochen’s part

  • Path-Specific Counterfactuals

attended this tutorial

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The effects of treatment T on outcome Y had X been x’

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Causal Inference Tasks

  • Counterfactual Analysis

19

Jundong

Yaochen

M1 = Jundong’s part

M2 = Yaochen’s part

  • Path-Specific Counterfactuals

What if Judea Pearl had given Yaochen’s part?

M2 = Judea Pearl

attended this tutorial

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The effects of treatment T on outcome Y had X been x’

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Causal Inference Tasks

  • Counterfactual Analysis

20

Jundong

Yaochen

M1 = Jundong’s part

M2 = Yaochen’s part

  • Path-Specific Counterfactuals

What if Judea Pearl had given Yaochen’s part?

M2 = Judea Pearl

attended this tutorial

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

your research

The effects of treatment T on outcome Y had X been x’

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Fundamental Challenge of Causal Inference

  • Missing Data Problem

21

  • CI requires comparing the same units that undergoes different treatments

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Fundamental Challenge of Causal Inference

  • Missing Data Problem

Professors

22

Jundong

Yaochen

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

  • CI requires comparing the same units that undergoes different treatments

compare

with the same group

parallel universe 1

parallel universe 2

Ph.D. students

Area Chairs

Professors

Area Chairs

Ph.D. students

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e.,

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Fundamental Challenge of Causal Inference

  • Missing Data Problem

Professors

23

Jundong

Yaochen

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

  • CI requires comparing the same units that undergoes different treatments

compare

with the same group

parallel universe 1

parallel universe 2

Ph.D. students

Area Chairs

Professors

Area Chairs

Ph.D. students

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e.,

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Fundamental Challenge of Causal Inference

  • Missing Data Problem

Professors

24

Jundong

Yaochen

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

However, this is fundamentally impossible in real world…

  • CI requires comparing the same units that undergoes different treatments

compare

with the same group

parallel universe 1

parallel universe 2

Ph.D. students

Area Chairs

Professors

Area Chairs

Ph.D. students

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e.,

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Fundamental Challenge of Causal Inference

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  • One group of units we observe take the treatment
  • Missing Data Problem – what we have:

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Fundamental Challenge of Causal Inference

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  • One group of units we observe take the treatment

real universe

treatment group (T=1)

  • Missing Data Problem – what we have:

Jundong

Yaochen

Ph.D. students

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Fundamental Challenge of Causal Inference

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  • Another group of different units we observe take no treatment

real universe

real universe

treatment group (T=1)

non-treatment group (T=0)

  • Missing Data Problem – what we have:

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • One group of units we observe take the treatment

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Fundamental Challenge of Causal Inference

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Comparable?

Different units

  • Another group of different units we observe take no treatment

real universe

real universe

treatment group (T=1)

non-treatment group (T=0)

  • Missing Data Problem – what we have:

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • One group of units we observe take the treatment

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Fundamental Challenge of Causal Inference

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  • What if we ignore the missing data mechanism?

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Fundamental Challenge of Causal Inference

  • Consider the following case

30

Y before

Y before

real universe

real universe

treatment group (T=1)

non-treatment group (T=0)

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • People need more causal knowledge turned to attend this tutorial

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Fundamental Challenge of Causal Inference

  • Consider the following case

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  • People need more causal knowledge turned to attend this tutorial

Y after

  • These people can gain more knowledge than experts who ignore the tutorial

Y before

Y before

Y after

real universe

real universe

treatment group (T=1)

non-treatment group (T=0)

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Fundamental Challenge of Causal Inference

  • Consider the following case

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  • People need more causal knowledge turned to attend this tutorial

Y after

  • These people can gain more knowledge than experts who ignore the tutorial

Y before

Y before

Y after

real universe

real universe

treatment group (T=1)

non-treatment group (T=0)

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

group-wise, attending tutorial helps your productivity (which makes us happy)

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Fundamental Challenge of Causal Inference

  • Consider the following case

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Y after

Y before

Y before

Y after

unobserved

unobserved

comparison across group leads us to believe that tutorial hurts productivity

treatment group (T=1)

non-treatment group (T=0)

real universe

real universe

  • People need more causal knowledge turned to attend this tutorial
  • These people can gain more knowledge than experts who ignore the tutorial

Jundong

Yaochen

Ph.D. students

Professors

Area Chairs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Causal Inference in a Nutshell

  • Symbol Systems

34

to reason with causal relations

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Causal Inference in a Nutshell

  • Symbol Systems

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  • Identifiability Theorems

to show that under certain conditions, causal reasoning can be derived from observed statistical relations

to reason with causal relations

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Common Definitions

  • Unit (i)

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the atomic research object in the study.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Common Definitions

  • Unit (i)

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  • Treatment (T)

(the cause we wanna study)

the atomic research object in the study.

an action that applies to a unit.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

attend causal inference tutorial

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Common Definitions

  • Unit (i)

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  • Treatment (T)

(the cause we wanna study)

  • Outcome (Y)

(the effect we are interested in)

the atomic research object in the study.

an action that applies to a unit.

response of the units after treatment.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

attend causal inference tutorial

I have a good idea

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Rubin’s Causal Model (RCM)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • Stable Unit Treatment Value Assumption (SUTVA)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • Stable Unit Treatment Value Assumption (SUTVA)

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  • PO does not vary with the treatment assigned to other units

Jundong

Yaochen

attend this tutorial (T = 1)

real universe for i

Ti = 1

Yi (1)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • Stable Unit Treatment Value Assumption (SUTVA)

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  • PO does not vary with the treatment assigned to other units
  • There are no different forms of treatments

Jundong

Yaochen

attend this tutorial (T = 1)

real universe for i

Ti = 1

Yi (1)

Jundong

Yaochen

attend this tutorial (T = 1)

real universe for i

leave half-way

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • Potential Outcome

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

def. the outcome Y if treatment t is applied on unit i.

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Rubin’s Causal Model (RCM)

  • Potential Outcome

real universe for i

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def. the outcome Y if treatment t is applied on unit i.

Jundong

Yaochen

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

i

i

Yi(1)

Yi(0)

parallel universe 2

e.g., in our previous example,

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • Potential Outcome

real universe for i

45

Jundong

Yaochen

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

i

i

parallel universe 2

potential outcomes Yi(1) and Yi(0) cannot be simultaneously observed

e.g., in our previous example,

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Yi(1)

Yi(0)

def. the outcome Y if treatment t is applied on unit i.

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Rubin’s Causal Model (RCM)

  • Observed Outcome

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

def. the actual outcome Y on unit i under observed treatment.

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Rubin’s Causal Model (RCM)

  • Observed Outcome

47

Jundong

Yaochen

i

i

Yi(0)

real universe for i

counterfactual universe for i

e.g., in our previous example, if unit i attends the tutorial

unobserved

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Yi

def. the actual outcome Y on unit i under observed treatment.

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Rubin’s Causal Model (RCM)

  • Observed Outcome

48

Jundong

Yaochen

i

i

Yi(0)

real universe for i

counterfactual universe for i

Yi(t) and Yi reason with outcome from an individual perspective

e.g., in our previous example, if unit i attends the tutorial

unobserved

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Yi

def. the actual outcome Y on unit i under observed treatment.

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Rubin’s Causal Model (RCM)

  • Potential Outcome Random Variable

49

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

def. distribution of outcome Y if treatment t is uniformly applied

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Rubin’s Causal Model (RCM)

50

Jundong

Yaochen

Y (1)

parallel universe 1

parallel universe 2

e.g., in our previous example,

Y (0)

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Potential Outcome Random Variable

def. distribution of outcome Y if treatment t is uniformly applied

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Rubin’s Causal Model (RCM)

  • Potential Outcome Random Variable

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Jundong

Yaochen

Y (1)

parallel universe 1

parallel universe 2

Y(T=t) cannot be measured due to unobserved potential outcomes

e.g., in our previous example,

Y (0)

attend this tutorial (T = 1)

ignore this tutorial (T = 0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

def. distribution of outcome Y if treatment t is uniformly applied

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Rubin’s Causal Model (RCM)

  • With potential outcome, we can define:

52

  • average treatment effect (ATE)

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

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  • average treatment effect (ATE)
  • average treatment effect on the treated (ATT)

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • With potential outcome, we can define:

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Rubin’s Causal Model (RCM)

  • With potential outcome, we can define:

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  • average treatment effect (ATE)
  • average treatment effect on the treated (ATT)

 

  • conditional average treatment effect (CATE)

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

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  • individual treatment effect (ITE)

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • average treatment effect (ATE)
  • average treatment effect on the treated (ATT)

 

  • conditional average treatment effect (CATE)

 

 

  • With potential outcome, we can define:

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Rubin’s Causal Model (RCM)

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  • individual treatment effect (ITE)

 

Question: How to estimate the above causal estimands?

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • average treatment effect (ATE)
  • average treatment effect on the treated (ATT)

 

  • conditional average treatment effect (CATE)

 

 

  • With potential outcome, we can define:

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Rubin’s Causal Model (RCM)

  • A Naïve Estimator for ATE

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

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Rubin’s Causal Model (RCM)

  • A Naïve Estimator for ATE

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Jundong

real universe

real universe

 

average Y for treated students

average Y for non-treated professors

Ph.D. students

Professors

Area Chairs

treatment group (T=1)

Yaochen

non-treatment group (T=0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Rubin’s Causal Model (RCM)

  • A Naïve Estimator for ATE

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Jundong

real universe

real universe

 

average Y for treated students

average Y for non-treated professors

Ph.D. students

Professors

Area Chairs

treatment group (T=1)

Yaochen

non-treatment group (T=0)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

There are systematic differences between the treatment/non-treatment group

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Rubin’s Causal Model (RCM)

  • A Naïve Estimator for ATE

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Jundong

real universe

real universe

 

average Y for treated students

average Y for non-treated professors

With no further assumptions, the naïve estimator is biased!!

Ph.D. students

Professors

Area Chairs

treatment group (T=1)

Yaochen

non-treatment group (T=0)

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Rubin’s Causal Model (RCM)

  • Positivity Assumption

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Treatment assignment cannot be deterministic

P(T = 1, 0|X = x) > 0 for all X = x

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Rubin’s Causal Model (RCM)

  • Positivity Assumption

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Treatment assignment cannot be deterministic

P(T = 1, 0|X = x) > 0 for all X = x

Jundong

real universe

Ph.D. students

Professors

Area Chairs

treatment group (T=1)

Yaochen

non-treatment group (T=0)

Bad universe that violates the positivity assumption!

real universe

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Rubin’s Causal Model (RCM)

  • Positivity Assumption

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Jundong

Yaochen

Ph.D. students

real universe

Professors

treatment group (T=1)

non-treatment group (T=0)

real universe

Area Chairs

Area Chairs

Professors

Treatment assignment cannot be deterministic

P(T = 1, 0|X = x) > 0 for all X = x

Ph.D. students

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Rubin’s Causal Model (RCM)

  • Positivity Assumption

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Jundong

Yaochen

Ph.D. students

real universe

Professors

treatment group (T=1)

non-treatment group (T=0)

real universe

Area Chairs

Area Chairs

Professors

Treatment assignment cannot be deterministic

P(T = 1, 0|X = x) > 0 for all X = x

Ph.D. students

Difference between two groups is alleviated, as student/AC/Prof. are in both groups

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Rubin’s Causal Model (RCM)

  • Unconfoundedness

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

PO R.V. Y(T) are independent of treatment assignment T

Y(t) ⊥ T, for all T = t

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Rubin’s Causal Model (RCM)

  • Unconfoundedness

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

real universe

treatment group (T=1)

non-treatment group (T=0)

real universe

PO R.V. Y(T) are independent of treatment assignment T

Y(t) ⊥ T, for all T = t

Ph.D. students

Area Chairs

Professors

Professors

Area Chairs

Ph.D. students

Jundong

Yaochen

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Rubin’s Causal Model (RCM)

  • Unconfoundedness

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

real universe

treatment group (T=1)

non-treatment group (T=0)

real universe

PO R.V. Y(T) are independent of treatment assignment T

Y(t) ⊥ T, for all T = t

Ph.D. students

Area Chairs

Professors

Professors

Area Chairs

Ph.D. students

Jundong

Yaochen

Difference between two groups is vanished!!

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Rubin’s Causal Model (RCM)

  • Unconfoundedness

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

real universe

treatment group (T=1)

non-treatment group (T=0)

real universe

PO R.V. Y(T) are independent of treatment assignment T

Y(t) ⊥ T, for all T = t

Ph.D. students

Area Chairs

Professors

Professors

Area Chairs

Ph.D. students

Jundong

Yaochen

Problem: too strong…conditional version introduced later…

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Structural Causal Model (SCM)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Structural Causal Model (SCM)

  • Causal Graph (G)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. A direct acyclic graph (DAG) that encodes the assumed causal relations among variables of interest

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Structural Causal Model (SCM)

  • Causal Graph (G)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • three atomic structures

(a) Chain

T

M

Y

tutorial

presenter

research productivity

Def. A direct acyclic graph (DAG) that encodes the assumed causal relations among variables of interest

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Structural Causal Model (SCM)

  • Causal Graph (G)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • three atomic structures

(a) Chain

(b) Fork

T

M

Y

T

Y

C

tutorial

presenter

research productivity

tutorial

research productivity

knowledge level of audience

Def. A direct acyclic graph (DAG) that encodes the assumed causal relations among variables of interest

Spuriously correlates T and Y if C is NOT considered!!

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Structural Causal Model (SCM)

  • Causal Graph (G)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. A direct acyclic graph (DAG) that encodes the assumed causal relations among variables of interest

  • three atomic structures

Spuriously correlates T and Y if M is conditioned on!!

(b) Fork

(c) V-structure

T

Y

C

Y

T

M

tutorial

research productivity

knowledge level of audience

tutorial

research productivity

# papers

(a) Chain

T

M

Y

tutorial

presenter

research productivity

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Structural Causal Model (SCM)

  • Exogenous Variables (U)

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Def. Variables out of the study that influence variables in the study

(i.e., endogenous variables)

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Structural Causal Model (SCM)

  • Exogenous Variables (U)

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Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Variables out of the study that influence variables in the study

(a) population level

T

Y

C

tutorial

research productivity

knowledge level of audience

  • take the fork structure as an example:

(i.e., endogenous variables)

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Structural Causal Model (SCM)

  • Exogenous Variables (U)

76

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Variables out of the study that influence variables in the study

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

T

Y

C

tutorial

research productivity

knowledge level of audience

  • take the fork structure as an example:

(b) individual level

(a) population level

U1

U2

U3

77 of 384

Structural Causal Model (SCM)

  • Exogenous Variables (U)

77

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Variables out of the study that influence variables in the study

U are important to consider for individual treatment effects!

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

T

Y

C

tutorial

research productivity

knowledge level of audience

  • take the fork structure as an example:

(b) individual level

(a) population level

U1

U2

U3

78 of 384

Structural Causal Model (SCM)

  • Structure Equations (F)

78

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify the causal influence of causal parents to the child node

79 of 384

Structural Causal Model (SCM)

  • Structure Equations (F)

79

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify the causal influence of causal parents to the child node

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

U1

U2

U3

qualify causal relations

  • causal graph

80 of 384

Structural Causal Model (SCM)

  • Structure Equations (F)

80

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify the causal influence of causal parents to the child node

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

U1

U2

U3

  • C = fc (U2)

  • T = ft (U1, C)

  • Y = fy (U3, C, T)

qualify causal relations

quantify causal influence

  • causal graph
  • structural eqs.

81 of 384

Structural Causal Model (SCM)

  • Structure Equations (F)

81

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify the causal influence of causal parents to the child node

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

U1

U2

U3

  • C = fc (U2)

  • T = ft (U1, C)

  • Y = fy (U3, C, T)

qualify causal relations

quantify causal influence

  • causal graph
  • structural eqs.

remark#1. structural equations represent the underlying physical world

82 of 384

Structural Causal Model (SCM)

  • Structure Equations (F)

82

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify the causal influence of causal parents to the child node

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

U1

U2

U3

  • C = fc (U2)

  • T = ft (U1, C)

  • Y = fy (U3, C, T)

qualify causal relations

quantify causal influence

  • causal graph
  • structural eqs.

remark#2. structural equations usually needs to be estimated from data

83 of 384

Structural Causal Model (SCM)

  • Intervention on SCM

83

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Study the causal influence of treatment node on the target node

84 of 384

Structural Causal Model (SCM)

  • Intervention on SCM

84

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Study the causal influence of treatment node on the target node

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

U1

U2

U3

  • causal graph

85 of 384

Structural Causal Model (SCM)

  • Intervention on SCM

85

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Study the causal influence of treatment node on the target node

do(T=1)

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

U2

U3

  • intervened causal graph

your mood

U1

86 of 384

Structural Causal Model (SCM)

  • Intervention on SCM

86

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Study the causal influence of treatment node on the target node

Y

C

research productivity

knowledge level of audience

your perseverance

your previous education

U2

U3

  • intervened causal graph

force everyone to attend the tutorial

your mood

U1

regardless of the mood, previous education, etc.

do(T=1)

tutorial

87 of 384

Structural Causal Model (SCM)

  • Intervention on SCM

87

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Study the causal influence of treatment node on the target node

Y

C

research productivity

knowledge level of audience

your perseverance

your previous education

U2

U3

  • intervened causal graph

force everyone to attend the tutorial

your mood

U1

regardless of the mood, previous education, etc.

  • C = fc (U2)

  • T = ft (U1, C) -> T = 1

  • Y = fy (U3, C, T)
  • intervened structural Eqs

do(T=1)

tutorial

88 of 384

Latent Variables in Causal Inference

  • Latent variables are ubiquitous in various CI tasks

88

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

89 of 384

Latent Variables in Causal Inference

  • Latent variables are ubiquitous in various CI tasks

89

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Carelessly addressing them jeopardizes the inference results

90 of 384

Latent Variables in Causal Inference

  • Treatment Effect Estimation

90

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between T and Y

91 of 384

Latent Variables in Causal Inference

  • Treatment Effect Estimation

91

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between T and Y

T

Y

C

tutorial

research productivity

knowledge level of audience

T

Y

tutorial

research productivity

(a) no confounder

(b) unobserved confounder

92 of 384

Latent Variables in Causal Inference

  • Treatment Effect Estimation

92

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level of audience

C may not be observed if we don’t have the attendant demographical data

T

Y

tutorial

research productivity

(a) no confounder

(b) unobserved confounder

confounders C leads to spurious correlation between T and Y

93 of 384

Latent Variables in Causal Inference

  • Causal Mediation Analysis

93

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between

  • T and Y
  • T and M
  • M and Y

T

M

Y

tutorial

different parts

research productivity

94 of 384

Latent Variables in Causal Inference

  • Causal Mediation Analysis

94

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between

  • T and Y
  • T and M
  • M and Y

T

M

Y

tutorial

different parts

research productivity

C

research interest

Determines whether or not you will attend it

95 of 384

Latent Variables in Causal Inference

  • Causal Mediation Analysis

95

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between

  • T and Y
  • T and M
  • M and Y

T

M

Y

tutorial

different parts

research productivity

C

research interest

Determines which part you pay most attention to

Determines whether or not you will attend it

96 of 384

Latent Variables in Causal Inference

  • Causal Mediation Analysis

96

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between

  • T and Y
  • T and M
  • M and Y

T

M

Y

tutorial

different parts

research productivity

C

research interest

Determines which part you pay most attention to

Determines also research productivity

Determines whether or not you will attend it

97 of 384

Latent Variables in Causal Inference

  • Causal Mediation Analysis

97

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounders C leads to spurious correlation between

  • T and Y
  • T and M
  • M and Y

T

M

Y

tutorial

different parts

research productivity

C

research interest

Determines which part you pay most attention to

Determines also research productivity

C may not be observed if we don’t have the attendant background data

Determines whether or not you will attend it

98 of 384

Latent Variables in Causal Inference

  • Counterfactual Analysis

98

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Individual factors (i.e., exogenous variables) are usually not observed

99 of 384

Latent Variables in Causal Inference

  • Counterfactual Analysis

99

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Individual factors (i.e., exogenous variables) are usually not observed

T

Y

C

tutorial

research productivity

knowledge level of audience

your perseverance

your previous education

your mood

100 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

100

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

101 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

101

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Circumvention-based Method

Show that under certain conditions, we can eschew the latent variables

102 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

102

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Circumvention-based Method

Show that under certain conditions, we can eschew the latent variables

T

Y

C

tutorial

research productivity

knowledge level of audience

  • we anticipate that:
  • we decide to:

T

Y

tutorial

research productivity

I

draw lots

e.g.,

103 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

103

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Circumvention-based Method

Since T is randomly assigned, C cannot be a causal parent of T

Show that under certain conditions, we can eschew the latent variables

T

Y

C

tutorial

research productivity

knowledge level of audience

  • we anticipate that:
  • we decide to:

T

Y

tutorial

research productivity

I

draw lots

e.g.,

104 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

104

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Inference-based Method

Infer the latent variables from other observed covariates

105 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

105

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Inference-based Method

Infer the latent variables from other observed covariates

T

Y

C

tutorial

research productivity

knowledge level of audience

  • we anticipate that:

E.g.,

  • but we observe age

106 of 384

Latent Variables in Causal Inference

  • Two Strategies to Address Latent Variables

106

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Inference-based Method

Infer the latent variables from other observed covariates

T

Y

C

tutorial

research productivity

knowledge level of audience

  • we anticipate that:

E.g.,

  • but we observe age

Age could be an indicator for the knowledge level!

107 of 384

Outline

Background and Causal Inference Basics

Counterfactual Analysis

Latent Confounding Analysis

107

Latent Mediation Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Challenges & Future Directions

Generalization to Graphs

108 of 384

Background Knowledge

  • Confounder Revisits

108

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Covariates that simultaneously affect the treatment T and outcome Y

109 of 384

Background Knowledge

  • Confounder Revisits

109

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Covariates that simultaneously affect the treatment T and outcome Y

T

Y

C

tutorial

research productivity

knowledge level of audience

  • causal graph

110 of 384

Background Knowledge

  • Confounder Revisits

110

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Covariates that simultaneously affect the treatment T and outcome Y

  • causal graph
  • sample-based view

T

Y

C

tutorial

research productivity

knowledge level of audience

treatment group (T=1)

non-treatment group (T=0)

111 of 384

Background Knowledge

  • Confounder Revisits

111

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Covariates that simultaneously affect the treatment T and outcome Y

  • causal graph
  • omniscient view

T

Y

C

tutorial

research productivity

knowledge level of audience

treatment group (T=1)

non-treatment group (T=0)

lead to systematic difference between the treatment/non-treatment groups

Professors

Area chair

Area chairs

Professors

Ph.D. level

Ph.D. level

112 of 384

Traditional Methods

  • Conditional Ignorability Assumption

112

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

113 of 384

Traditional Methods

  • Conditional Ignorability Assumption

113

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

research productivity

knowledge level

(one possible case)

  • causal graph

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

114 of 384

Traditional Methods

  • Conditional Ignorability Assumption

114

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

research productivity

knowledge level

  • causal graph

giving you an exam before you enter this tutorial

measured by

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

(one possible case)

115 of 384

Traditional Methods

  • Conditional Ignorability Assumption

115

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • causal graph
  • sample-based view

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

(one possible case)

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

116 of 384

Traditional Methods

  • Conditional Ignorability Assumption

116

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Wholistically, the treatment are not randomly assigned

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • causal graph
  • sample-based view

(one possible case)

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

117 of 384

Traditional Methods

  • Conditional Ignorability Assumption

117

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

For each sub-population, treatment are randomly assigned (same color)

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • causal graph
  • sample-based view

(one possible case)

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

118 of 384

Traditional Methods

  • Conditional Ignorability Assumption

118

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

For each sub-population, treatment are randomly assigned (same color)

(with possibly different probability of treatment assignment)

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • causal graph
  • sample-based view

(one possible case)

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

119 of 384

Traditional Methods

  • Conditional Ignorability Assumption

119

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Expected Y(0) for sub-treatment group should be same as sub-non-treatment group

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • causal graph
  • sample-based view

(one possible case)

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

E[Y(0)|x]

E[Y(0)|x]

120 of 384

Traditional Methods

  • Conditional Ignorability Assumption

120

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Expected Y(1) for sub-non-treatment group should be same as sub-treatment group

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • sample-based view

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

T

Y

X

tutorial

  • causal graph

(one possible case)

knowledge level

research productivity

E[Y(1)|x]

E[Y(1)|x]

121 of 384

Traditional Methods

  • Conditional Ignorability Assumption

121

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • causal graph that violates CI

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

122 of 384

Traditional Methods

  • Conditional Ignorability Assumption

122

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

  • causal graph that violates CI

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

123 of 384

Traditional Methods

  • Conditional Ignorability Assumption

123

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

  • causal graph that violates CI

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

C

seniority level

124 of 384

Traditional Methods

  • Conditional Ignorability Assumption

124

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

Ph.D. level

Professors

Ph.D. level

Area chair

Area chairs

Professors

treatment group (T=1)

non-treatment group (T=0)

  • causal graph that violates CI
  • sample-based view

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

C

seniority level

125 of 384

Traditional Methods

  • Conditional Ignorability Assumption

125

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

Ph.D. level

APs

Senior Ph.D.

Area chair

SAC

Full Prof.

treatment group (T=1)

non-treatment group (T=0)

  • causal graph that violates CI

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

C

seniority level

  • omniscient view

126 of 384

Traditional Methods

  • Conditional Ignorability Assumption

126

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

X

tutorial

Ph.D. level

APs

Senior Ph.D.

Area chair

SAC

Full Prof.

treatment group (T=1)

non-treatment group (T=0)

  • causal graph that violates CI

Y(t) are independent of treatment T given observed covariates X

Y(t) ⊥ T | X = x, for all T = t, X=x

knowledge level

research productivity

C

seniority level

  • omniscient view

Conditional on X CANNOT eliminate the systematic difference between two groups

127 of 384

Traditional Methods

  • Covariate Adjustment

127

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

128 of 384

Traditional Methods

  • Covariate Adjustment

128

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Controlling for the effects of observed confounders

129 of 384

Traditional Methods

  • Covariate Adjustment

129

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

  • Derivation

(the definition of ATE)

  • sample-based view

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

Controlling for the effects of observed confounders

130 of 384

Traditional Methods

  • Covariate Adjustment

130

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

(the definition of ATE)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 0

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

131 of 384

Traditional Methods

  • Covariate Adjustment

131

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

(the definition of ATE)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 1

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

132 of 384

Traditional Methods

  • Covariate Adjustment

132

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

(the definition of ATE)

(law of total expectation)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

133 of 384

Traditional Methods

  • Covariate Adjustment

133

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

(the definition of ATE)

(law of total expectation)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

(we first ignore the outer E, and focus on the inter with X = Ph.D. student)

134 of 384

Traditional Methods

  • Covariate Adjustment

134

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

(the definition of ATE)

(law of total expectation)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 0

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

(we first ignore the outer E, and focus on the inter with X = Ph.D. student)

135 of 384

Traditional Methods

  • Covariate Adjustment

135

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

(the definition of ATE)

(law of total expectation)

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 1

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

136 of 384

Traditional Methods

  • Covariate Adjustment

136

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

137 of 384

Traditional Methods

  • Covariate Adjustment

137

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 0

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

138 of 384

Traditional Methods

  • Covariate Adjustment

138

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

139 of 384

Traditional Methods

  • Covariate Adjustment

139

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

missing data from T = 1

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

140 of 384

Traditional Methods

  • Covariate Adjustment

140

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

141 of 384

Traditional Methods

  • Covariate Adjustment

141

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

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Traditional Methods

  • Covariate Adjustment

142

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

is just the average observed Y for T=1

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

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Traditional Methods

  • Covariate Adjustment

143

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

chairs

treatment group (T=1)

non-treatment group (T=0)

Prof.

Ph.D.

 

is just the average observed Y for T=0

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

144 of 384

Traditional Methods

  • Covariate Adjustment

144

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Ph.D. effects

chairs effects

treatment group (T=1)

non-treatment group (T=0)

Prof. effects

(weighted average)

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

145 of 384

Traditional Methods

  • Covariate Adjustment

145

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Ph.D. effects

chairs effects

treatment group (T=1)

non-treatment group (T=0)

Prof. effects

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

Causal estimands are reduced to correlations measurable in dataset

Controlling for the effects of observed confounders

  • Derivation
  • sample-based view

(weighted average)

146 of 384

Traditional Methods

  • Covariate Adjustment

146

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

(a) linear regression

Causal estimands are reduced to correlations measurable in dataset

Controlling for the effects of observed confounders

  • Derivation
  • estimators

147 of 384

Traditional Methods

  • Covariate Adjustment

147

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

(a) linear regression

(b) trees

Causal estimands are reduced to correlations measurable in dataset

Controlling for the effects of observed confounders

  • Derivation
  • estimators

148 of 384

Traditional Methods

  • Covariate Adjustment

148

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

(the definition of ATE)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(consistency)

 

(a) linear regression

(b) trees

(c) deep neural networks

Causal estimands are reduced to correlations measurable in dataset

Controlling for the effects of observed confounders

  • Derivation
  • estimators

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Traditional Methods

  • Inverse Propensity Score Weighting

149

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

150 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

150

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Propensity Score: e = p(T | X = x)

151 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

151

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Def. Propensity Score: e = p(T | X = x)

i.e., the probability treatment is assigned for sub-population X = x

152 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

152

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • Theorem

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Traditional Methods

  • Inverse Propensity Score Weighting

153

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • Theorem

expected Y(T=1) for the whole population

  • sample-based view

treatment group (T=1)

non-treatment group (T=0)

Ph.D.

Area Chair

 

missing data from T = 0

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Traditional Methods

  • Inverse Propensity Score Weighting

154

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • Theorem

reweighted observed Y for the treatment group

  • sample-based view

treatment group (T=1)

non-treatment group (T=0)

Ph.D.

Area Chair

 

155 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

155

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • Theorem

 

156 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

156

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • sample-based view

treatment group (T=1)

non-treatment group (T=0)

Ph.D.

 

Area Chair

Profs.

 

e = 3/4

e = 1/3

e = 1/4

  • Theorem

157 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

157

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • sample-based view

treatment group (T=1)

non-treatment group (T=0)

Ph.D.

 

Area Chair

Profs.

 

e = 3/4

e = 1/3

e = 1/4

reweight by 4/3

  • Theorem

158 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

158

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • sample-based view

non-treatment group (T=0)

Ph.D.

Area Chair

Profs.

 

treatment group (T=1)

 

  • Theorem

159 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

159

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

Def. Propensity Score: e = p(T | X = x)

  • sample-based view

non-treatment group (T=0)

Ph.D.

Area Chair

Profs.

 

treatment group (T=1)

 

  • Theorem

160 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

160

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

(binary treatment + consistency)

(law of total expectation)

conditional ignorability, Y(t) ⊥ T | X = x

 

 

(definition of propensity score)

 

law of total expectation

Def. Propensity Score: e = p(T | X = x)

  • Derivation
  • sample-based view

non-treatment group (T=0)

Ph.D.

Area Chair

Profs.

treatment group (T=1)

 

161 of 384

Traditional Methods

  • Inverse Propensity Score Weighting

161

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

(binary treatment + consistency)

(law of total expectation)

(conditional ignorability, Y(t) ⊥ T | X = x

(definition of propensity score)

(law of total expectation)

Def. Propensity Score: e = p(T | X = x)

  • Derivation
  • sample-based view

non-treatment group (T=0)

Ph.D.

Area Chair

Profs.

treatment group (T=1)

 

e can be estimated via linear regression, trees, and deep neural networks

 

 

 

 

 

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Question

  • What if Conditional Ignorability Does Not Hold?

162

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e., some confounders are not observed in X

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Question

  • What if Conditional Ignorability Does Not Hold?

163

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e., some confounders are not observed in X

x

treatment group (T=1)

non-treatment group (T=0)

age: young

age: old

age: young

age: old

  • sample-based view

observed covariates X

164 of 384

Question

  • What if Conditional Ignorability Does Not Hold?

164

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e., some confounders are not observed in X

The population

Ph.D.

Area Chair

Profs.

treatment group (T=1)

non-treatment group (T=0)

age: young

age: old

age: young

age: old

  • omniscient view

select

select

observed covariates X

true confounders C

165 of 384

Question

  • What if Conditional Ignorability Does Not Hold?

165

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

i.e., some confounders are not observed in X

The population

Ph.D.

Area Chair

Profs.

treatment group (T=1)

non-treatment group (T=0)

age: young

age: old

age: young

age: old

  • omniscient view

select

select

In each sub-population specified by X = x, systematic difference still exists

166 of 384

Circumvention-based Method

  • Objective

166

show that under certain conditions, we can eschew the latent variable

while obtain unbiased estimate of the causal estimands

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

167 of 384

Circumvention-based Method

  • With Randomized Data

167

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

168 of 384

Circumvention-based Method

  • With Randomized Data

168

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The naïve estimator ER[Y|T=1] - ER[Y|T=0] is unbiased for ATE

randomized data distribution

169 of 384

Circumvention-based Method

  • With Randomized Data

169

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The population

treatment group (T=1)

non-treatment group (T=0)

age: young

The naïve estimator ER[Y|T=1] - ER[Y|T=0] is unbiased for ATE

randomized data distribution

However, the size of randomized data could be very small:

age: old

age: old

age: young

Ph.D.

Area Chair

Profs.

170 of 384

Circumvention-based Method

  • With Randomized Data

170

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

However, the size of randomized data could be very small:

The population

treatment group (T=1)

non-treatment group (T=0)

random sample

random sample

The naïve estimator ER[Y|T=1] - ER[Y|T=0] is unbiased for ATE

randomized data distribution

age: young

age: young

age: old

age: old

Ph.D.

Area Chair

Profs.

171 of 384

Circumvention-based Method

  • With Randomized Data

171

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

However, the size of randomized data could be very small:

The population

treatment group (T=1)

non-treatment group (T=0)

random sample

random sample

The naïve estimator ER[Y|T=1] - ER[Y|T=0] is unbiased for ATE

randomized data distribution

age: young

age: young

age: old

age: old

Ph.D.

Area Chair

Profs.

172 of 384

Circumvention-based Method

  • With Randomized Data

172

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

However, the size of randomized data could be very small:

The population

treatment group (T=1)

non-treatment group (T=0)

random sample

random sample

The naïve estimator ER[Y|T=1] - ER[Y|T=0] is unbiased for ATE

randomized data distribution

age: young

age: old

age: young

age: old

The variance of the estimator will be very large

Ph.D.

Area Chair

Profs.

173 of 384

Circumvention-based Method

  • With Randomized Data

173

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

A large observational data DO with unobserved confounders

A small randomized data DR

Problem Setting:

174 of 384

Circumvention-based Method

  • With Randomized Data

174

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data
  • Randomized data

Problem Setting:

X = young

X = old

X = young

X = old

175 of 384

Circumvention-based Method

  • With Randomized Data

175

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

fit a base estimator y = fO(x, t)

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

Problem Setting:

  • Randomized data

X = young

X = old

X = young

X = old

Kallus, Nathan, Aahlad Manas Puli, and Uri Shalit. "Removing hidden confounding by experimental grounding." Advances in neural information processing systems 31 (2018).

176 of 384

Circumvention-based Method

  • With Randomized Data

176

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

Problem Setting:

X = young

X = old

X = young

X = old

  • Randomized data

due to selection on true confounder C

fit a base estimator y = fO(x, t)

It is biased for E [Y(t) | X=x]

177 of 384

Circumvention-based Method

  • With Randomized Data

177

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

evaluate the residual of fO(x, t) on DO

fit a base estimator y = fO(x, t)

It is biased for E [Y(t) | X=x]

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

Problem Setting:

X = young

X = old

X = young

X = old

due to selection on true confounder C

  • Randomized data

178 of 384

Circumvention-based Method

  • With Randomized Data

178

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

evaluate the residual of fO(x, t) on DO

fit fR(x, t) on the residual

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

Problem Setting:

X = young

X = old

X = young

X = old

fit a base estimator y = fO(x, t)

It is biased for E [Y(t) | X=x]

due to selection on true confounder C

  • Randomized data

179 of 384

Circumvention-based Method

  • With Randomized Data

179

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

fO(x, t) + fR(x, t) is an unbiased estimator for E [Y(t) | X=x]

fit fR(x, t) on the residual

A large observational data DO with unobserved confounders

A small randomized data DR

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

Problem Setting:

X = young

X = old

X = young

X = old

fit a base estimator y = fO(x, t)

It is biased for E [Y(t) | X=x]

due to selection on true confounder C

evaluate the residual of fO(x, t) on DO

  • Randomized data

180 of 384

Circumvention-based Method

  • With Randomized Data

180

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

If residual is small, estimation variance can be substantially reduced

fit fR(x, t) on the residual

randomized treatment group (T=1)

treatment group (T=1)

  • Observational data

X = young

X = old

X = young

X = old

fit a base estimator y = fO(x, t)

It is biased for E [Y(t) | X=x]

due to selection on true confounder C

A large observational data DO with unobserved confounders

A small randomized data DR

Problem Setting:

  • Randomized data

evaluate the residual of fO(x, t) on DO

181 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

181

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

182 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

182

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(i) has no confounding with the outcome Y

  • Causal Graph

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

183 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

183

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

184 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

184

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(iii) affects the outcome 𝑌 only through 𝑇 (restriction)

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

185 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

185

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(iii) affects the outcome 𝑌 only through 𝑇 (restriction)

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

I

X

advisor randomly coerce Ph.D. to attend tutorial based on their mood

treatment

outcome

unobserved confounder

instrumental variable

observed covariates

IV (advisor coercion):

186 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

186

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(iii) affects the outcome 𝑌 only through 𝑇 (restriction)

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

I

X

treatment

outcome

unobserved confounder

instrumental variable

observed covariates

whether or not you wanna listen to them by attending this tutorial

T (attend the tutorial):

advisor randomly coerce Ph.D. to attend tutorial based on their mood

IV (advisor coercion):

187 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

187

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(iii) affects the outcome 𝑌 only through 𝑇 (restriction)

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

I

X

treatment

outcome

unobserved confounder

instrumental variable

observed covariates

whether or not you wanna listen to them by attending this tutorial

T (attend the tutorial):

advisor randomly coerce Ph.D. to attend tutorial based on their mood

IV (advisor coercion):

compliance to treatment (I -> T measures intention for treatment)

188 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

188

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

IV is a variable that

(iii) affects the outcome 𝑌 only through 𝑇 (restriction)

(i) has no confounding with the outcome Y

(ii) affects the treatment T (relevance)

  • Causal Graph

T

Y

C

I

X

treatment

outcome

unobserved confounder

instrumental variable

observed covariates

whether or not you wanna listen to them by attending this tutorial

T (attend the tutorial):

advisor randomly coerce Ph.D. to attend tutorial based on their mood

IV (advisor coercion):

The effect between T and Y is what we really wanna estimate…

189 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

189

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

The two stage algorithm

190 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

190

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Causal Graph

The two stage algorithm

191 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

191

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Assumption

Y = f(X, T) + C

(additive confounders)

(1)

  • Causal Graph

The two stage algorithm

192 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

192

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Assumption
  • Causal Graph

Y = f(X, T) + C

(additive confounders)

  • Analysis

E[Y|X, I] = E[f(X, T)|X, I] +E[C|X]

(1)

(taking expectation of Eq. 1)

The two stage algorithm

193 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

193

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Assumption
  • Causal Graph

Y = f(X, T) + C

(additive confounders)

  • Analysis

E[Y|X, I] = E[f(X, T)|X, I] +E[C|X]

(1)

(taking expectation of Eq. 1)

 

(law of total expectation)

The two stage algorithm

194 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

194

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Assumption
  • Causal Graph

Y = f(X, T) + C

(additive confounders)

  • Analysis

E[Y|X, I] = E[f(X, T)|X, I] +E[C|X]

(1)

(taking expectation of Eq. 1)

 

(law of total expectation)

 

(change of name)

The two stage algorithm

195 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

195

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

treatment

outcome

unobserved confounder

I

instrumental variable

observed covariates

X

  • Assumption
  • Causal Graph

Y = f(X, T) + C

(additive confounders)

  • Analysis

E[Y|X, I] = E[f(X, T)|X, I] +E[C|X]

(1)

(taking expectation of Eq. 1)

 

(law of total expectation)

 

(change of name)

The two stage algorithm

exactly the causal estimand we are interested in

196 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

196

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

From the above derivation we have:

 

a new T conditional on X, I

causal estimand

The two stage algorithm

observed Y

197 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

197

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

a new T conditional on X, I

causal estimand

The two stage algorithm

observed Y

198 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

198

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Algorithm
  • Regress X, I on T and get the predicted value T’
  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

a new T conditional on X, I

causal estimand

The two stage algorithm

observed Y

199 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

199

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Algorithm
  • Regress X, I on T and get the predicted value T’
  • Regress T’, X on Y, where the coefficient gives the CATE
  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

observed Y

a new T conditional on X, I

causal estimand

The two stage algorithm

200 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

200

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Algorithm
  • Regress X, I on T and get the predicted value T’
  • Regress T’, X on Y, where the coefficient gives the CATE
  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

observed Y

a new T conditional on X, I

causal estimand

The two stage algorithm

  • Regress T’ on Y, where the coefficient gives the ATE

201 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

201

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Algorithm
  • Regress X, I on T and get the predicted value T’
  • Regress T’, X on Y, where the coefficient gives the CATE
  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

observed Y

a new T conditional on X, I

causal estimand

The two stage algorithm

  • Regress T’ on Y, where the coefficient gives the ATE

Issue #1: Instrumental variables are difficult to obtain

202 of 384

Circumvention-based Method

  • Instrumental Variables (IV)

202

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Algorithm
  • Regress X, I on T and get the predicted value T’
  • Regress T’, X on Y, where the coefficient gives the CATE
  • Assumption

The relation between Y, X, I, T are linear

From the above derivation we have:

 

observed Y

a new T conditional on X, I

causal estimand

The two stage algorithm

  • Regress T’ on Y, where the coefficient gives the ATE

Issue #2: Weak IV leads to high estimation variance

This will be very small

203 of 384

Circumvention-based Method

  • Front-door Adjustment

203

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

204 of 384

Circumvention-based Method

  • Front-door Adjustment

204

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

smoke

lung cancer

T

  • Exemplar causal graph

205 of 384

Circumvention-based Method

  • Front-door Adjustment

205

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

smoke

lung cancer

T

  • Exemplar causal graph

C

smoking gene

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Circumvention-based Method

  • Front-door Adjustment

206

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

C

smoke

lung cancer

T

M

smoking gene

  • Exemplar causal graph

tar deposit

207 of 384

Circumvention-based Method

  • Front-door Adjustment

207

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

C

smoke

lung cancer

T

M

smoking gene

  • Exemplar causal graph

tar deposit

tar deposit satisfy the front-door criterion!

208 of 384

Circumvention-based Method

  • Front-door Adjustment

208

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

C

smoke

lung cancer

T

M

smoking gene

  • Exemplar causal graph

tar deposit

tar deposit satisfy the front-door criterion!

  • Strategy:

p(M | do(T)) = p(M | T)

causal influence from T to M:

209 of 384

Circumvention-based Method

  • Front-door Adjustment

209

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

C

smoke

lung cancer

T

M

smoking gene

  • Exemplar causal graph

tar deposit

tar deposit satisfy the front-door criterion!

  • Strategy:

p(M | do(T)) = p(M | T)

causal influence from T to M:

causal influence from M to Y:

 

As Y <- C -> T -> M forms a backdoor path

210 of 384

Circumvention-based Method

  • Front-door Adjustment

210

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

ATE can be identified with known, unconfounded, sufficient mediator

Y

C

smoke

lung cancer

T

M

smoking gene

  • Exemplar causal graph

tar deposit

tar deposit satisfy the front-door criterion!

  • Strategy:

the treatment effect can be calculated as

 

p(M | do(T)) = p(M | T)

causal influence from T to M:

causal influence from M to Y:

 

As Y <- C -> T -> M forms a backdoor path

211 of 384

Inference-based Method

  • Objective

211

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

show that under certain conditions, latent confounders can be inferred

from other observed variables

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Inference-based Method

  • Proxy-based Method

212

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

213 of 384

Inference-based Method

  • Proxy-based Method

213

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

General analysis of proxy of confounders

214 of 384

Inference-based Method

  • Proxy-based Method

214

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

General analysis of proxy of confounders

age for knowledge level

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Inference-based Method

  • Proxy-based Method

215

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • Theorem

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

General analysis of proxy of confounders

ATE can be unbiasedly estimated if

p(T, Y, C, X) can be identified.

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Inference-based Method

  • Proxy-based Method

216

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • Theorem

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

  • Proof

 

(law of total expectation)

General analysis of proxy of confounders

ATE can be unbiasedly estimated if

p(T, Y, C, X) can be identified.

217 of 384

Inference-based Method

  • Proxy-based Method

217

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • Theorem

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

  • Proof

 

 

(law of total expectation)

(conditional ignorability)

General analysis of proxy of confounders

ATE can be unbiasedly estimated if

p(T, Y, C, X) can be identified.

218 of 384

Inference-based Method

  • Proxy-based Method

218

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

T

Y

C

X

treatment

outcome

unobserved confounders

confounder proxies

  • Proof

(law of total expectation)

(conditional ignorability)

Both p(Y|X, T, C) and p(C, T|X) can be derived from p(T, Y, C, X)

General analysis of proxy of confounders

 

 

  • Theorem

ATE can be unbiasedly estimated if

p(T, Y, C, X) can be identified.

219 of 384

Inference-based Method

  • Proxy-based Method

219

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal effect variational auto-encoder (CEVAE)

220 of 384

Inference-based Method

  • Proxy-based Method

220

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

Non-treatment branch

Treatment branch

Covariate

branch

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

221 of 384

Inference-based Method

  • Proxy-based Method

221

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal effect variational auto-encoder (CEVAE)

p(T, Y, C, X) = p(C) ⨉ p(T | C) ⨉ p(Y | C, T) ⨉ p(X | C)

T

Y

C

X

222 of 384

Inference-based Method

  • Proxy-based Method

222

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

T

Y

C

X

p(T, Y, C, X) = p(C)p(T | C) ⨉ p(Y | C, T) ⨉ p(X | C)

223 of 384

Inference-based Method

  • Proxy-based Method

223

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

p(T, Y, C, X) = p(C) ⨉ p(T | C) p(Y | C, T) ⨉ p(X | C)

224 of 384

Inference-based Method

  • Proxy-based Method

224

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

Non-treatment branch

Treatment branch

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

p(T, Y, C, X) = p(C) ⨉ p(T | C) ⨉ p(Y | C, T) p(X | C)

225 of 384

Inference-based Method

  • Proxy-based Method

225

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

Non-treatment branch

Treatment branch

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

p(T, Y, C, X) = p(C) ⨉ p(T | C) ⨉ p(Y | C, T) p(X | C)

two-branch network to avoid ignoring the T information

226 of 384

Inference-based Method

  • Proxy-based Method

226

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

Non-treatment branch

Treatment branch

Covariate

branch

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

p(T, Y, C, X) = p(C) ⨉ p(T | C) ⨉ p(Y | C, T) ⨉ p(X | C)

227 of 384

Inference-based Method

  • Proxy-based Method

227

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Generation Stage

Non-treatment branch

Treatment branch

Covariate

branch

latent confounder C

P(T | C)

P(X | C)

P(Y | C, T=0)

P(Y | C, T=1)

Causal effect variational auto-encoder (CEVAE)

Treatment prediction

T

Y

C

X

p(T, Y, C, X) = p(C) ⨉ p(T | C) ⨉ p(Y | C, T) ⨉ p(X | C)

The generation network can be trained with observed (X, T, Y)

228 of 384

Inference-based Method

  • Proxy-based Method

228

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal effect variational auto-encoder (CEVAE)

Q(C|T, Y, X) - > variational posterior

229 of 384

Inference-based Method

  • Proxy-based Method

229

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounder proxies X

Q(T|X)

Q(C|Y, T=0, X)

Q(C|Y, T=0, X)

Non-treatment branch

Treatment branch

Causal effect variational auto-encoder (CEVAE)

  • Inference Stage

Q(C|T, Y, X) - > variational posterior

two-branch network to avoid ignoring the T information

Q(Y|T=0, X)

Q(Y|T=1, X)

230 of 384

Inference-based Method

  • Proxy-based Method

230

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

confounder proxies X

Q(T|X)

Q(Y|T=0, X)

Q(Y|T=1, X)

Q(C|Y, T=0, X)

Q(C|Y, T=0, X)

Cascade inference to allow estimation for test data with missing covariates

Non-treatment branch

Treatment branch

Causal effect variational auto-encoder (CEVAE)

  • Inference Stage

Q(C|T, Y, X) - > variational posterior

231 of 384

Inference-based Method

  • Covariate Disentanglement

231

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

General analysis of latent variables in X

232 of 384

Inference-based Method

  • Covariate Disentanglement

232

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

General analysis of latent variables in X

233 of 384

Inference-based Method

  • Covariate Disentanglement

233

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • General Analysis
  • Controlling confounder C:

reduce bias

General analysis of latent variables in X

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

234 of 384

Inference-based Method

  • Covariate Disentanglement

234

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • General Analysis

adjustors

  • Controlling confounder C:

reduce bias

  • Controlling adjustor A:

reduce variance

General analysis of latent variables in X

(less variability of Y when A is controlled)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

I.V.

235 of 384

Inference-based Method

  • Covariate Disentanglement

235

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • General Analysis
  • Controlling confounder C:

reduce bias

  • Controlling adjustor A:

reduce variance

  • Controlling IV I:

increase both bias and variance

General analysis of latent variables in X

(less variability of Y when A is controlled)

(may leave open backdoor path)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

236 of 384

Inference-based Method

  • Covariate Disentanglement

236

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • General Analysis
  • Controlling confounder C:

reduce bias

  • Controlling adjustor A:

reduce variance

  • Controlling IV I:

increase both bias and variance

General analysis of latent variables in X

(less variability of Y when A is controlled)

(may leave open backdoor path)

(imbalance treatment/non-treatment group)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

237 of 384

Inference-based Method

  • Covariate Disentanglement

237

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • General Analysis
  • Controlling confounder C:

reduce bias

  • Controlling adjustor A:

reduce variance

  • Controlling IV I:

increase both bias and variance

We should exclude latent IV from the control set

General analysis of latent variables in X

(less variability of Y when A is controlled)

(may leave open backdoor path)

(imbalance treatment/non-treatment group)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

238 of 384

Inference-based Method

  • Covariate Disentanglement

238

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

I.V.

Treatment effect estimation with disentangled latent factors (TEDVAE)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

239 of 384

Inference-based Method

  • Covariate Disentanglement

239

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • Observation

I is predictive only for T

A is predictive only for Y

C is predictive for both T and Y

Treatment effect estimation with disentangled latent factors (TEDVAE)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

240 of 384

Inference-based Method

  • Covariate Disentanglement

240

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph
  • Observation

I is predictive only for T

A is predictive only for Y

C is predictive for both T and Y

  • Approach

infer Z = {I, A, C} via CEVAE

max. p(T|C, I), p(Y|C, A)

Treatment effect estimation with disentangled latent factors (TEDVAE)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

241 of 384

Inference-based Method

  • Covariate Disentanglement

241

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal Graph

The constraint encourages the disentanglement of I, C, A

  • Observation

I is predictive only for T

A is predictive only for Y

C is predictive for both T and Y

  • Approach

Treatment effect estimation with disentangled latent factors (TEDVAE)

infer Z = {I, A, C} via CEVAE

max. p(T|C, I), p(Y|C, A)

T

Y

C

X

treatment

outcome

confounders

confounder proxies

I

A

adjustors

I.V.

242 of 384

Outline

242

Background and Causal Inference Basics

Counterfactual Analysis

Latent Confounding Analysis

Latent Mediation Analysis

Challenges & Future Directions

Generalization to Graphs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

243 of 384

243

 

 

Latent Mediation Analysis

  • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health situation

244 of 384

244

 

 

 

(nutrition)

Latent Mediation Analysis

  • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health situation

245 of 384

245

 

 

 

 

(nutrition)

Latent Mediation Analysis

  • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

emotions

good diet

health situation

246 of 384

246

 

 

 

 

(nutrition)

Latent Mediation Analysis

  • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

emotions

good diet

health situation

247 of 384

247

 

 

 

 

 

emotions

Latent Mediation Analysis

  • Background

(nutrition)

good diet

health situation

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

248 of 384

248

  • Mediation Effects Formulation

Latent Mediation Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Natural indirect effect

 

249 of 384

Latent Mediation Analysis

249

 

 

 

bad diet

emotions

(nutrition)

 

good diet

health

nested potential outcome

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

intervention T = 1 on path T -> M -> Y

intervention T = 0 on path T -> Y

  • Mediation Effects Formulation
  • Natural indirect effect

 

250 of 384

Latent Mediation Analysis

  • Mediation Effects Formulation

250

intervention T = 1 on path T -> M -> Y

intervention T = 0 on path T -> Y

 

 

 

 

intervention T = 0 on path T -> M -> Y

intervention T = 0 on path T -> Y

 

 

 

bad diet

emotions

(nutrition)

health

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

bad diet

emotions

good diet

health

nested potential outcome

  • Natural indirect effect

 

(nutrition)

251 of 384

Latent Mediation Analysis

  • Mediation Effects Formulation

251

intervention T = 0 on path T -> M -> Y

intervention T = 1 on path T -> Y

 

 

 

 

intervention T = 0 on path T -> M -> Y

intervention T = 0 on path T -> Y

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

(nutrition)

bad diet

emotions

(nutrition)

health

good diet

emotions

bad diet

health

 

  • Natural direct effect

252 of 384

252

T

M

 

 

 

 

 

 

  • Sequential Ignorability:

good diet

health situation

(nutrition)

Latent Mediation Analysis

  • Assumptions for Traditional Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

253 of 384

253

T

M

 

 

 

 

 

 

 

  • Sequential Ignorability:

stress level

emotions

 

(nutrition)

Latent Mediation Analysis

  • Assumptions for Traditional Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health situation

254 of 384

254

T

Y

M

 

 

 

 

  • Sequential Ignorability:

social support

 

(nutrition)

Latent Mediation Analysis

  • Assumptions for Traditional Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

emotions

good diet

health situation

255 of 384

255

T

Y

M

 

 

 

 

  • Sequential Ignorability:

environmental factors

(e.g., pollution)

good diet

health situation

(nutrition)

 

Latent Mediation Analysis

  • Assumptions for Traditional Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

emotions

256 of 384

Latent Mediation Analysis

  • Assumptions for Traditional Methods

256

 

 

 

  • Sequential Ignorability:

  • Measurable Mediator:

 

(nutrition)

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health situation

emotions

257 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

257

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Natural indirect effect

 

258 of 384

Latent Mediation Analysis

258

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Natural indirect effect

 

  • Quantify Mediation Effects

259 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

259

control for observed confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

  • Natural indirect effect

 

260 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

260

Let T=1 affect Y through M

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

  • Natural indirect effect

 

261 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

261

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Let T=1 affect Y through M

 

 

Let T=0 affect Y through M

  • Natural indirect effect

262 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

262

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

  • Natural indirect effect

Let T=0 directly affect Y

263 of 384

Latent Mediation Analysis

  • Quantify Mediation Effects

263

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

  • Natural indirect effect

Let T=0 directly affect Y

  • Natural direct effect

264 of 384

Latent Mediation Analysis

  • Traditional Method

264

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

265 of 384

Latent Mediation Analysis

  • Traditional Method

265

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Regress:

(no M)

total effect

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

266 of 384

Latent Mediation Analysis

  • Traditional Method

266

 

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Regress:

(no M)

total effect

effect of T on M

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

267 of 384

Latent Mediation Analysis

  • Traditional Method

267

 

 

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Regress:

(no M)

total effect

effect of T on M

direct effect of T on M

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

268 of 384

Latent Mediation Analysis

  • Traditional Method

268

 

 

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Regress:

(no M)

total effect

effect of T on M

direct effect of T on M

effect of M on Y

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

269 of 384

Latent Mediation Analysis

  • Traditional Method

269

 

 

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Mediation Effect:

Regress:

(no M)

effect of T on M

effect of M on Y

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

270 of 384

Latent Mediation Analysis

  • Traditional Method

270

 

 

 

 

 

 

 

 

 

 

Linear structural equation modeling (LSEM)

Mediation Effect:

Regress:

(no M)

total effect

direct effect of T on M

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

271 of 384

Latent Mediation Analysis

  • Latent confounders

271

 

 

 

 

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

272 of 384

Latent Mediation Analysis

  • Latent confounders

272

 

 

 

 

 

 

 

 

  • Problem

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

273 of 384

Latent Mediation Analysis

  • Latent confounders

273

 

 

 

 

 

 

 

 

 

 

  • Problem

 

 

  • Solution

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

274 of 384

274

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

Inference-based Method for Latent CMA

  • Latent confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

275 of 384

Inference-based Method for Latent CMA

275

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

 

 

  • Latent confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

  • recall that natural indirect effect is defined as:

276 of 384

276

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

 

 

 

 

  • Derivation

Inference-based Method for Latent CMA

  • Latent confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

277 of 384

277

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

 

 

 

 

 

(law of total expectation)

  • Derivation

Inference-based Method for Latent CMA

  • Latent confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

278 of 384

278

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

 

 

(law of total expectation)

 

(remove do-calculus by no confoundedness)

  • Derivation

Inference-based Method for Latent CMA

 

 

 

 

  • Latent confounders

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

279 of 384

Inference-based Method for Latent CMA

279

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Framework
  • Encoder:

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

280 of 384

Inference-based Method for Latent CMA

280

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Encoder:

cascadedly infer t, M, y, Z to allow missing values for inference

 

  • Proxy-based Method
  • Framework

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

281 of 384

Inference-based Method for Latent CMA

281

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Decoder:

 

  • Encoder:

 

  • Proxy-based Method
  • Framework

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

282 of 384

Inference-based Method for Latent CMA

282

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Inference Stage

 

 

 

 

two-branch network to avoid forgetting t

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

283 of 384

Inference-based Method for Latent CMA

283

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Generation Stage

 

 

 

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

284 of 384

Inference-based Method for Latent CMA

284

[1] Lu Cheng, Ruocheng Guo, and Huan Liu. 2022. Causal Mediation Analysis with Hidden Confounders. WSDM.

  • Objective

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Causal mediation analysis variational auto-encoder (CMAVAE)

285 of 384

Latent Mediation Analysis – Part II

285

  • Latent Mediator

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

important mediator can also be difficult to measure

286 of 384

Latent Mediation Analysis – Part II

286

Example

  • Latent Mediator

 

emotions

good diet

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

health

important mediator can also be difficult to measure

287 of 384

Latent Mediation Analysis – Part II

287

Example

unknown mediator violates the measurable mediator assumption.

  • Latent Mediator
  • Problem

 

emotions

good diet

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

health

important mediator can also be difficult to measure

288 of 384

Latent Mediation Analysis – Part II

288

Example

  • Latent Mediator
  • Problem
  • Solution

unknown mediator violates the measurable mediator assumption.

approximate latent mediator with proxy variables.

 

emotions

good diet

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

health

important mediator can also be difficult to measure

289 of 384

289

 

emotions

Example

  • Latent Mediator

 

$money you make

Latent Mediation Analysis – Part II

  • Problem
  • Solution

unknown mediator violates the measurable mediator assumption.

approximate latent mediator with proxy variables.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health

important mediator can also be difficult to measure

290 of 384

290

 

emotions

Example

  • Latent Mediator

 

 

#paper you publish

Latent Mediation Analysis – Part II

$money you make

  • Problem
  • Solution

unknown mediator violates the measurable mediator assumption.

approximate latent mediator with proxy variables.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

good diet

health

important mediator can also be difficult to measure

291 of 384

Inference-based Method for Latent CMA

291

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

Example

 

 

#paper you publish

$money you make

good diet

health

generalized structural equations model (GSEM)

292 of 384

Inference-based Method for Latent CMA

292

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

Example

 

 

#paper you publish

$money you make

good diet

health

generalized structural equations model (GSEM)

293 of 384

Inference-based Method for Latent CMA

293

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

Example

 

 

#paper you publish

$money you make

good diet

health

latent variables

generalized structural equations model (GSEM)

294 of 384

Inference-based Method for Latent CMA

294

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

Example

 

 

#paper you publish

$money you make

good diet

health

learnable parameters

generalized structural equations model (GSEM)

295 of 384

Inference-based Method for Latent CMA

295

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

  • Proxy-based Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

Example

 

 

#paper you publish

$money you make

good diet

health

learnable parameters

EM-algorithm!

generalized structural equations model (GSEM)

296 of 384

Inference-based Method for Latent CMA

296

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

emotions

 

 

#paper you publish

$money you make

good diet

health

  • Proxy-based Method

Example

 

^

 

^

^

generalized structural equations model (GSEM)

297 of 384

Inference-based Method for Latent CMA

297

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

 

emotions

 

 

#paper you publish

$money you make

good diet

health

  • Proxy-based Method

Example

 

 

^

^

^

^

generalized structural equations model (GSEM)

298 of 384

Inference-based Method for Latent CMA

298

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

  • Mediation effect estimation:

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

 

 

#paper you publish

$money you make

good diet

health

  • Proxy-based Method

Example

generalized structural equations model (GSEM)

299 of 384

Inference-based Method for Latent CMA

299

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

  • Mediation effect estimation:

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

 

 

#paper you publish

$money you make

good diet

health

(substitute with the estimated parameters)

  • Proxy-based Method

Example

generalized structural equations model (GSEM)

300 of 384

Inference-based Method for Latent CMA

300

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

  • Mediation effect estimation:

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

emotions

 

 

#paper you publish

$money you make

good diet

health

(Monte Carlo estimator)

(substitute with the estimated parameters)

  • Proxy-based Method

Example

generalized structural equations model (GSEM)

301 of 384

Inference-based Method for Latent CMA

301

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

[2] Sun, Rongqian, Xiaoxiao Zhou, and Xinyuan Song. "Bayesian causal mediation analysis with latent mediators and survival outcome." Structural Equation Modeling: A Multidisciplinary Journal 28.5 (2021): 778-790.

 

 

 

 

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Proxy-based Method

In reality, there may exist multiple mediators either parallel or causally.

302 of 384

Inference-based Method for Latent CMA

302

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

[2] Sun, Rongqian, Xiaoxiao Zhou, and Xinyuan Song. "Bayesian causal mediation analysis with latent mediators and survival outcome." Structural Equation Modeling: A Multidisciplinary Journal 28.5 (2021): 778-790.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

 

 

 

 

  • Proxy-based Method

In reality, there may exist multiple mediators either parallel or causally.

303 of 384

Inference-based Method for Latent CMA

303

  • Method

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

[2] Sun, Rongqian, Xiaoxiao Zhou, and Xinyuan Song. "Bayesian causal mediation analysis with latent mediators and survival outcome." Structural Equation Modeling: A Multidisciplinary Journal 28.5 (2021): 778-790.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

 

 

 

 

  • Proxy-based Method
  • Linearly formulate causal equations that allow interactions.

In reality, there may exist multiple mediators either parallel or causally.

304 of 384

Inference-based Method for Latent CMA

304

  • Method

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

[2] Sun, Rongqian, Xiaoxiao Zhou, and Xinyuan Song. "Bayesian causal mediation analysis with latent mediators and survival outcome." Structural Equation Modeling: A Multidisciplinary Journal 28.5 (2021): 778-790.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

 

 

 

 

  • Proxy-based Method
  • Linearly formulate causal equations that allow interactions.
  • Set prior distribution of the parameters

In reality, there may exist multiple mediators either parallel or causally.

305 of 384

Inference-based Method for Latent CMA

305

  • Method

[1] Albert, Jeffrey M., Cuiyu Geng, and Suchitra Nelson. "Causal mediation analysis with a latent mediator." Biometrical Journal 58.3 (2016): 535-548.

[2] Sun, Rongqian, Xiaoxiao Zhou, and Xinyuan Song. "Bayesian causal mediation analysis with latent mediators and survival outcome." Structural Equation Modeling: A Multidisciplinary Journal 28.5 (2021): 778-790.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

 

 

 

 

  • Proxy-based Method
  • Linearly formulate causal equations that allow interactions.
  • Set prior distribution of the parameters
  • Same old EM algorithm

In reality, there may exist multiple mediators either parallel or causally.

306 of 384

Outline

306

Background and Causal Inference Basics

Counterfactual Analysis

Latent Confounding Analysis

Latent Mediation Analysis

Challenges & Future Directions

Generalization to Graphs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

307 of 384

Counterfactual Analysis

307

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

  • Causal graph revisit

knowledge level

308 of 384

Counterfactual Analysis

308

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit

309 of 384

Counterfactual Analysis

309

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit
  • question

if you attended the tutorial (T=1) and had high research productivity (Y=1),

310 of 384

Counterfactual Analysis

310

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit
  • question

if you attended the tutorial (T=1) and had high research productivity (Y=1),

what would your research productivity be if you had not attended the tutorial?

311 of 384

Counterfactual Analysis

311

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit
  • question
  • abductive reasoning

you might be in a good mood

if you attended the tutorial (T=1) and had high research productivity (Y=1),

what would your research productivity be if you had not attended the tutorial?

312 of 384

Counterfactual Analysis

312

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit
  • question
  • abductive reasoning

you might be in a good mood

you might have high perseverance

if you attended the tutorial (T=1) and had high research productivity (Y=1),

what would your research productivity be if you had not attended the tutorial?

313 of 384

Counterfactual Analysis

313

    • Background

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

tutorial

research productivity

knowledge level

perseverance

your previous education

your mood

  • Causal graph revisit
  • question
  • abductive reasoning

you might be in a good mood

you might have high perseverance

Answer: your research productivity may drop, but is still higher than average

if you attended the tutorial (T=1) and had high research productivity (Y=1),

what would your research productivity be if you had not attended the tutorial?

314 of 384

Counterfactual Analysis

314

    • General Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal graph

T

Y

C

U1

U3

U2

315 of 384

Counterfactual Analysis

315

    • General Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Causal graph

T

Y

C

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

U1

U3

U2

316 of 384

Counterfactual Analysis

316

    • General Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

  • Causal graph

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

The population distribution of U

U1

U2

U3

317 of 384

Counterfactual Analysis

317

    • General Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

  • purpose

(1) reason with and (2) quantify the outcome of an individual had some observed variables X = x been x’

  • Causal graph

U1

U2

U3

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

318 of 384

Counterfactual Analysis

318

    • General Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

T

Y

C

U1

U2

U3

  • purpose

due to abductive reasoning, counterfactual reasoning is a latent variable problem!

  • challenge

(1) reason with and (2) quantify the outcome of an individual had some observed variables X = x been x’

  • Causal graph

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

319 of 384

Counterfactual Analysis

319

 

Exogenous variables

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

    • Reason with Counterfactuals

T

Y

C

  • Causal graph

intervention

observations

  • Counterfactual random variable

U1

U2

U3

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

320 of 384

Counterfactual Analysis

320

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

    • Quantify with Counterfactuals

T

Y

C

  • Causal graph

 

  • Counterfactual random variable

U1

U2

U3

U ~ p(U), C = fc(U2)

T = ft(C, U1)

Y = fy(T, C, U3)

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

321 of 384

Counterfactual Analysis

321

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

    • Quantify with Counterfactuals

Y

C

U ~ p(U|Z, t), C = fc(U2)

T = t’

Y = fy(T, C, U3)

  • Causal graph

 

 

  • Calculation
  • Counterfactual random variable
  • abduction

T

U1

U2

U3

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

322 of 384

Counterfactual Analysis

322

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

    • Quantify with Counterfactuals

Do(T=t’)

Y

C

U2

U3

U ~ p(U|Z, t), C = fc(U2)

T = t’

Y = fy(T, C, U3)

  • Causal graph

 

 

 

  • Calculation
  • Counterfactual random variable
  • abduction
  • action

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

323 of 384

Counterfactual Analysis

323

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

    • Quantify with Counterfactuals

Do(T=t’)

Y

C

U2

U3

U ~ p(U|Z, t), C = fc(U2)

T = t’

Y = fy(T, C, U3)

  • Causal graph

 

 

 

 

  • Calculation
  • Counterfactual random variable
  • abduction
  • action
  • prediction

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

324 of 384

Counterfactual Analysis

Aim: latent exogenous variables may not be explicitly calculated if counterfactuals of interest do not need to be quantified.

324

    • Circumvention-based Methods

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

325 of 384

Counterfactual Analysis

325

    • Circumvention-based Methods

 

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Example: Counterfactual Fairness

Treatment T = S, i.e., sensitive user features such as gender/age/race

machine learning predictor

Aim: latent exogenous variables may not be explicitly calculated if counterfactuals of interest do not need to be quantified.

326 of 384

Counterfactual Analysis

Aim: latent exogenous variables may not be explicitly calculated if counterfactuals of interest do not need to be quantified.

326

    • Circumvention-based Methods

 

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Example: Counterfactual Fairness

Treatment T = S, i.e., sensitive user features such as gender/age/race

S

Y

C

U1

U3

Y

C

U3

do(S=s’)

U2

U2

s-abducted

s-abducted

factual world

counterfactual world

327 of 384

Counterfactual Analysis

    • Sufficient condition

327

    • Circumvention-based Methods

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

Example: Counterfactual Fairness

328 of 384

Counterfactual Analysis

    • Sufficient condition

328

    • Circumvention-based Methods

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

    • Proof

 

 

only affect S and its causal descendent.

Example: Counterfactual Fairness

329 of 384

Counterfactual Analysis

329

    • Inference-based Methods

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Quantify counterfactuals by inferring the latent exogenous variables

330 of 384

Counterfactual Analysis

330

    • Inference-based Methods

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Problem Setting: predict the first-year average grade (FYA)

331 of 384

Counterfactual Analysis

331

    • Inference-based Methods
  • Sensitive attributes:

race (R) and sex (S)

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Problem Setting: predict the first-year average grade (FYA)

332 of 384

Counterfactual Analysis

332

    • Inference-based Methods
  • Sensitive attributes:

race (R) and sex (S)

  • Exogenous variables:

knowledge (K)

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Problem Setting: predict the first-year average grade (FYA)

333 of 384

Counterfactual Analysis

333

    • Inference-based Methods
  • Sensitive attributes:

race (R) and sex (S)

  • Exogenous variables:

knowledge (K)

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Problem Setting: predict the first-year average grade (FYA)

observed covariates

334 of 384

Counterfactual Analysis

334

Fair Add: a fitting model for counterfactual fairness.

    • Inference-based Methods
  • Assumption:

 

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

linear additive deterministic model.

335 of 384

Counterfactual Analysis

335

Fair Add: a fitting model for counterfactual fairness.

    • Inference-based Methods

  • Method:

  • Linearly fit the GPA and LSAT with race and sex.

  • Utilize the fitting errors as estimand to linear predict FYA.

Kusner, Matt J., et al. "Counterfactual fairness." Advances in neural information processing systems 30 (2017).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Assumption:

linear additive deterministic model.

Since the errors are exogenous, the prediction is unbiased

336 of 384

Counterfactual Analysis

336

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Fair Relax: counterfactual fairness with unknown SCM.

337 of 384

Counterfactual Analysis

337

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

Fair Relax: counterfactual fairness with unknown SCM.

338 of 384

Counterfactual Analysis

338

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

  • Method

dependence test to obtain skeleton

 

Fair Relax: counterfactual fairness with unknown SCM.

339 of 384

Counterfactual Analysis

339

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

Fair Relax: counterfactual fairness with unknown SCM.

340 of 384

Counterfactual Analysis

340

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

direction of other edges cannot be determined

Fair Relax: counterfactual fairness with unknown SCM.

341 of 384

Counterfactual Analysis

341

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

Fair Relax: counterfactual fairness with unknown SCM.

342 of 384

Counterfactual Analysis

342

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

Judge:

Fair Relax: counterfactual fairness with unknown SCM.

343 of 384

Counterfactual Analysis

343

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

It’s a non-descendent of S

Judge:

Fair Relax: counterfactual fairness with unknown SCM.

344 of 384

Counterfactual Analysis

344

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

It’s a non-descendent of S

Judge:

path 1

1

2

Fair Relax: counterfactual fairness with unknown SCM.

345 of 384

Counterfactual Analysis

345

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

It’s a non-descendent of S

Judge:

path 2

1

2

3

Fair Relax: counterfactual fairness with unknown SCM.

346 of 384

Counterfactual Analysis

346

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

It’s a non-descendent of S

Judge:

path 2

directed, not a chord!

1

2

3

Fair Relax: counterfactual fairness with unknown SCM.

347 of 384

Counterfactual Analysis

347

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

Otherwise, we cannot be sure

Judge:

path 1

a chord!

2

1

3

Fair Relax: counterfactual fairness with unknown SCM.

348 of 384

Counterfactual Analysis

348

Zuo, Aoqi, et al. "Counterfactual fairness with partially known causal graph." Advances in Neural Information Processing Systems 35 (2022): 1238-1252.

    • Inference-based Methods

 

 

 

  • Method

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

determine a partial DAG based on V-structure.

 

pair-wise examine S and another node, e.g., Z1

  1. if for all the paths in all the compatible DAG have no chord
  2. and have anti-causal link

Otherwise, we cannot be sure

Judge:

We should only include definite non-descendent of S for prediction

Fair Relax: counterfactual fairness with unknown SCM.

349 of 384

Counterfactual Analysis

349

    • Inference-based Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Path-specific counterfactuals

350 of 384

Counterfactual Analysis

350

 

 

 

 

 

race

    • Inference-based Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

culture

stereotype

Path-specific counterfactuals

purchases

351 of 384

Counterfactual Analysis

351

 

 

 

 

 

race

    • Inference-based Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

culture

stereotype

Path-specific counterfactuals

bias, should be avoided!

purchases

352 of 384

Counterfactual Analysis

352

 

 

 

 

 

race

    • Inference-based Methods

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

culture

stereotype

Path-specific counterfactuals

bias, should be avoided!

diversity, should be preserved!

purchases

353 of 384

Counterfactual Analysis

353

 

 

race

 

    • Inference-based Methods

  • Formulation:

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

 

 

 

 

 

factual value

purchases

culture

stereotype

counterfactual value

 

 

Path-specific causal effects

354 of 384

Counterfactual Analysis

354

Wu, Yongkai, et al. "Pc-fairness: A unified framework for measuring causality-based fairness." Advances in neural information processing systems 32 (2019)

 

    • Inference-based Methods

  • Formulation:

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

Path-specific causal effects

 

 

 

 

culture

stereotype

purchases

 

factual value

355 of 384

Counterfactual Analysis

355

 

 

 

Wu, Yongkai, et al. "Pc-fairness: A unified framework for measuring causality-based fairness." Advances in neural information processing systems 32 (2019)

    • Inference-based Methods
  • Challenge:

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

PC-Fairness: bounding path-specific counterfactual bias.

 

 

356 of 384

Counterfactual Analysis

356

 

 

 

Wu, Yongkai, et al. "Pc-fairness: A unified framework for measuring causality-based fairness." Advances in neural information processing systems 32 (2019)

    • Inference-based Methods

 

consider response functional

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

  • Challenge:

PC-Fairness: bounding path-specific counterfactual bias.

 

 

 

357 of 384

Counterfactual Analysis

357

 

Wu, Yongkai, et al. "Pc-fairness: A unified framework for measuring causality-based fairness." Advances in neural information processing systems 32 (2019)

    • Inference-based Methods
  • Theory: counterfactual effect is linear function of 𝐑’s values.

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

PC-Fairness: bounding path-specific counterfactual bias.

358 of 384

Counterfactual Analysis

358

 

Wu, Yongkai, et al. "Pc-fairness: A unified framework for measuring causality-based fairness." Advances in neural information processing systems 32 (2019)

    • Inference-based Methods
  • Theory: counterfactual effect is linear function of 𝐑’s values.

  • Bounding causal effect becomes linear optimization:

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

PC-Fairness: bounding path-specific counterfactual bias.

359 of 384

Outline

359

Background and Causal Inference Basics

Counterfactual Analysis

Challenges & Future Directions

Latent Confounding Analysis

Generalization to Graphs

Latent Mediation Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

360 of 384

Generalization to Graphs

360

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • What Are Graphs?

which have been extensively applied for real-world systems with connected units

Def. Units with interactions

Social Network

 

Citation Network

 

Knowledge Graph

For example, we have:

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Generalization to Graphs

361

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Causal Inference on Graphs

Wear Mask

Infection

causes

Answer causal questions when units have interactions

Consider the following example:

Question: how does the usage of face mask influence COVID-19 infection?

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Challenges for Causal Inference on Graph

362

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Challenge #1: Interference

Wear mask

Infection

Treatment

Outcome

causes

Ordinary graph

Hyperedge

The treatment of a unit may causally affect the outcome of other units

Examples:

On normal graphs

On hyper-graphs

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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363

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Challenge #2: Structure as Confounder

Wear mask

Infection

Treatment

Outcome

causes

Correlation

What if?

Confounder

Treatment

Outcome

 

 

 

Graph connections can also be confounding factor

Examples:

It is hard for traditional methods to control for these confounders

Challenges for Causal Inference on Graph

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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364

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Problem Definition

Causal Effects on Graphs

Given: observational data {X, A, T, Y}

node features

graph structure

treatments

outcomes

Aim:

      • For each node i: individual treatment effect (ITE)
      • For a certain group of nodes: conditional average treatment effect (CATE)

Wear mask

Infection

Treatment

Outcome

causes

ITE =

_

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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365

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Proxy-based Method

Causal Effects on Graphs

Key idea: Graphs serve as “proxies” for these hidden confounders

E.g., one’s economic status can often be reflected by their social network

Confounder representations

Graph data as confounder proxy

Effective deep representation learning

ITE Estimation based on confounder repr.

Overall Framework

ITE =

_

 

 

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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366

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Proxy-based Method

Causal Effects on Graphs

- Network Deconfounder

Figure: The workflow of network deconfounder [1]

 

GCN layers

 

 

Wasserstein-1

distance

Loss function

Outcome prediction loss

balancing

regularization

Confounder representation

Representation balancing

Outcome prediction

Guo, Ruocheng, et al. "Learning individual causal effects from networked observational data." WSDM. 2020.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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367

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Proxy-based Method

Causal Effects on Graphs

- DNDC for Dynamic Networks

Time

Key idea: Capture hidden confounders dynamic graph data

confounder representation learning

 

History embedding

Graph structure

Graph neural network

Ma, Jing, et al. "Deconfounding with networked observational data in a dynamic environment." ACM WSDM. 2021.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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368

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

    • Proxy-based Method

Causal Effects on Graphs

- Instrumental Variable

Key idea: Graph topology may be viewed as an instrumental variable (IV)

treatment

outcome

graph topology

hidden confounders

features

A valid IV must:

Recall that

    • Be relevant to the treatment
    • With causal effects on Y fully mediated by T
    • With no unblocked backdoor path from IV to Y

Ma, Jing, et al. "A Look into Causal Effects under Entangled Treatment in Graphs: Investigating the Impact of Contact on MRSA Infection." KDD. 2023.

Problem setting

Two-stage algorithms can be used to eliminate the confounding bias

In-room contacts

Room sharing network in hospital can serve as an IV

MRSA Infection

cause

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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369

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

Counterfactual Analysis on Graphs

    • Applications
    • Counterfactual-based graph generalization
    • Counterfactual graph fairness
    • Counterfactual graph explanation

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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  • Fairness: mitigate biases towards certain sensitive features.

370

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

Counterfactual Analysis on Graphs

    • Counterfactual Graph Fairness

 

Prediction

Graph

Graph ML model

How to mitigate biases towards underrepresented groups in graph ML?

(e.g., race, gender)

A natural question of fairness – What if ?

Will my application get approved if my gender/race/age had been different?

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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371

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

Counterfactual Analysis on Graphs

    • Counterfactual Graph Fairness - Gear

Ma, Jing, et al. Learning Fair Node Representations with Graph Counterfactual Fairness. WSDM, 2022.

Aim: (1) learn counterfactually fair node representations to mitigate bias from sensitive features of each node and their neighbors, (2) maintain good prediction performance

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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particularly useful if impossible to directly manipulate the factors of interest

372

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

Counterfactual Analysis on Graphs

    • Counterfactual Graph Explanation

Work experience: N/A

Work experience: 5 years

Original

Counterfactual

Aim: promotes model explainability by answering the key question:

An example of counterfactual explanation

how can I change to achieve a specific purpose.

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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373

Fairness in Graph Machine Learning: Recent Advances and Future Prospectives

Counterfactual Analysis on Graphs

    • Counterfactual Graph Explanation: CLEAR [1]

Aim: Generate counterfactual explanations (a graph slightly different from the original input) that lead to a desired output in graph-related predictors

Strategy: VAE with classifier guided generation

[1] Ma, Jing, et al. "CLEAR: Generative Counterfactual Explanations on Graphs." NeurIPS (2022).

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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Outline

374

Background and Causal Inference Basics

Counterfactual Analysis

Challenges & Future Directions

Latent Confounding Analysis

Generalization to Graphs

Latent Mediation Analysis

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

375 of 384

Future Directions

  • Theories and model design

  • Large language model (LLM)

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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On Theories and Model Design

  • Causal representation learning

Learn causal relationships and representations for high-level causal concepts from data

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On Theories and Model Design

  • Multi-modal causal inference

Visual

Language

Spatial

Audio

Temporal

Leverage causal knowledge from multiple modalities

Causal Inference with Latent Variables: Recent Advances and Future Prospectives

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On Theories and Model Design

  • Interpretation

Promote human understanding of causal models

Use causal knowledge to improve model explanation

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On Theories and Model Design

  • Uncertainty quantification

Quantify the uncertainty of causal inference and causal ML models

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Large Language Model (LLM)

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Large Language Model (LLM)

  • Identification of important latent variables

LLM

 

Use the inference capability and the common knowledge embedded in LLMs to identify unknown latent variables

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Large Language Model (LLM)

  • More proxies from language

LLM

Reason with new strategies to circumvent or infer the variables from proxy

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Large Language Model (LLM)

  • Natural language based interpretation

LLM

Design prompts to improve the understanding of causal inference for LLMs

LLMs provide natural language to explain causal inference process

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Q&A

03/08/2021

Thanks for listening!

Causal Inference with Latent Variables: Recent Advances and Future Prospectives