Causal Modeling & Simulation�Profs. Aseem Kaul & Andy Van de Ven�MGMT 8104, Research Design, Session 3�
Plan for Class
Discussion of Causal Modeling Readings/Video�
Chris Winchester | Formal modeling is very new to me, so my main struggle is wrapping my head around the process of developing a formal model. Can you provide an example of a formal model and how you went about developing this from the initial thought/RQ to the final (or most recent) version? I think this would be very helpful for me and others to see an example of model development "in action". | | |
Hanu | Is there a structure/guide to contrast the kind of problems that lend themselves naturally to models from those that do not? For example, a naive way would be to use models when data is hard to get | | |
Chelsea Garcia | The concept of "low hanging fruit" came up in the video and I am curious if there is still low hanging fruit to be uncovered in the HRD world? I haven't come across a lot of process model studies in the research. | | |
Bo Fang | It seems to me that we could use formal modeling to answer both "how" and "what" questions, but I wonder whether it belongs to the variance model or the process model, or is it a unique approach that we can consider using for any type of research problem/question? | | |
Jooyoun | 1. How could one critically review modeling papers? Are there things different from what we are trained to pay attention to when reviewing theory or empirical papers?�2. You've written out modeling papers with different approaches from a pure modeling paper to a hybrid of modeling and hypotheses testing. What led you to take different approaches? | | |
Justine Mishek | The idea of stacking simulations - or a building block approach - is also noted in the Harrison reading, particularly when seeking to uncover practical insights and use. (p1241, 2nd paragraph) Harrison also suggests that simulations should keep it simple. Overall, is simple viewed as 'elegant' or is simple considered 'less than' in academic circles? Is simplicity really the desired state in simulation circles? If not, could this lead to what Knudsen refers to as a 'cave of fellow modelers' and reduce the impact models /simulations can have in practice? | | |
Yeonjoo Lee |
How do you choose between modeling, empirical data, and mixed-method paper when you're designing a study? Do you recommend conducting a mixed-method study when it's possible? | | |
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Why build a model?
These benefits derive from (and come at the cost of) substantial simplification of the real world
Choosing a model
Analytical models
Simulations
Often useful to start from a pre-existing model and make changes to the set-up or relax prior assumptions, rather than starting from scratch
Designing a Formal Model (example 1)
Luo, Kaul, & Seo, SMJ (2018), ‘Winning us with trifles’
Q1. Model type: Analytical (variant of Rothschild & Stiglitz, 1976)
Q2. Key tension: Moral Hazard (philanthropy offers protection in case of accidents, but both philanthropy and accidents are firm choices)
Q3. Agents: Firms (2 types: clean & dirty); Society
Q4. Decision rules: Firms maximize profits; Society minimizes (or satisfices) accident frequency
Q5. Key Assumptions: Only the firm knows its type; firm can (partially) control accident probability
Q6. Parameters to vary: Society active vs. passive, Firms profit-maximizing vs. altruistic
Q7. Outcome measures: Corporate donations, Accident probability
Designing a Formal Model (example 2)
Chen, Kaul, and Wu, SMJ (2019), ‘Adaptation across multiple landscapes’
Q1. Model type: Simulation; variant of NK model (Levinthal, 1997)
Q2. Key tension: Sharing resources across businesses produces synergies, but also limits the firm’s ability to adapt
Q3. Agents: Diversified firm vs. 2 focused (single business) firms
Q4. Decision rules: Firms search locally; diversified firm maintains consistency across related decisions
Q5. Key Assumptions: Synergies between related businesses require coordination; diversified firm will always coordinate related elements (relaxed in supplementary analysis)
Q6. Parameters to vary: Relatedness between business, complexity within businesses, level of synergy
Q7. Outcome measures: Long-term diversification advantage
Exercise in Designing a Formal Model
Q1. What type of model would you choose?
Q2. What is the key tension / tradeoff you are trying to model?
Q3. Who are the agents in the model? how many of them are there and are they of different types?
Q4. What are decision rules each agent will follow?
Q5. What are the key assumptions that you will hold constant throughout the model?
Q6. What are the (1 or 2) key parameters you plan to vary?
Q7. What are the outcomes measures you want to track?
Breakout exercise: Discuss questions in pairs and then come back and share a few examples
Designing Simulation Modeling Studies
8
Harrison, Lin, Carroll & Carley, 2007. Simulation modeling in organizational and management research, AMR.
Kauffman’s NK(C) Model of Complexity
– N = # of Elements (Boolean Nodes) in the system
– K = degree of interdependence among elements (# of connections that a node accepts as inputs)
– C = degree of the system’s coupling with other coevolving systems in the landscape (# of connections each node has to nodes of another system)
Single vs. Rugged Landscape
Low K (Degree of interdependence)
Single peaked landscape
Rugged landscape
High K (Degree of interdependence)
Work Design Performance Landscapes�Internal and External Fit of Mass (Ford) and Lean (Japanese) �Automobile Production Systems in Early 1900s and in 1980s
The Ford production system in early 1900s
Rise of Japanese Production System in 1980s and relative decrease of the Ford system
Source. Siggelkow (2001, p. 840)
Empirical Modeling of Time Series Data
Problem:
Four Types of Empirical Time Series
Type of time series | Dimensionality (# of causal factors) | Type of Interaction between variables | Appropriate model |
Periodic | Low (2-3 dimensions) | Independent or linear | linear deterministic models (regression analysis) |
Chaotic | Low (5-9 dimensions) | Interdependent in a non linear fashion | NK(C) model * Fitness landscape |
Colored (pink) noise (generated according to power laws) | High (many dimensions) | Interdependent in a non linear fashion | NK(C) model * Fitness landscape |
White noise (Truly random dynamic) | High (many dimension) | Independent or linear | Probability models |
Adopted from Anderson et al. (1999) and Sinha and Van de Ven (2005). Designing work within and between organizations. Organization Science, 16(4), 389–408p.
Dynamical Landscape
Few variables acting
independently
Many variables acting
independently
Many variables acting
interdependently
Few variables acting
interdependently
Statistical
Analysis
CHAOS
PERIODIC
WHITE
NOISE
COLORED
NOISE
Self-Organizing Criticality:� CIP Actions in Beginning Period
log-normal: distributional fractal
Kevin Dooley
Diagnostic Tests for Chaotic and �Non-Linear Patterns in Time Series
Example of Modeling Complexity
Let us model the relative time spent on exploration versus exploitation activities over time in an organization with the following logistic map:
Xt = kXt-1(1-Xt-1)
Where:
Xt = if actions taken at time t are exploration
vs. exploitation activities
k = parameter governing the degree of non-linearity of the� equation
k = 1.8
k = 3.2
k = 3.7
When k in
Xt = kXt-1(1-Xt-1)
Equals:
Bifurcation Structure of the Limit Set of Logistic Map Xt = kXt-1 (1 – Xt-1) for varying values of k
Lorenz and Mandelbrot Attractors
Edward Lorenz Benoit Mandelbrot
A Chaotic Process is Dynamic, Non-Linear and Sensitive to Initial Conditions
Dynamic means that the values a variable takes on at any time t are a function (at least in part) of the values of that variable at an earlier time, e.g. path dependence.
A Chaotic Process is Dynamic, Non-Linear and Sensitive to Initial Conditions
Non-linearity implies that dynamic feedback loops vary in strength (loose or tight coupling) and direction (positive or negative) over time.
A Chaotic Process is Dynamic, Non-Linear and Sensitive to Initial Conditions
Small initial differences or fluctuations in variables may grow over time into large differences, and as they move further from equilibrium, they bifurcate or branch out into numerous possible pathways.
Problem
Next Class: Designing Process Research Models�
Plan for Class
Process research should be evaluated on its own terms;
not in terms of variance research models.
© Andrew H. Van de Ven, Carlson School, U. of Minnesota, MGMT8101 Theory Building & Research Design PhD Seminar
Exercise: Students share & assess their process study designs
Issues | Your Process Research Study |
1. State your process research question Whose viewpoint is featured? | Process models are geared to studying how questions |
2. State your key process proposition. What process theories do you examine? | Apply and compare plausible alternative models |
3. How define process ? What is your unit of analysis? | As an assumption, variable or event? Unit of time? |
4 What is your process research design? | - concepts/units examined over time - real-time or historical event data - archival, laboratory, or field study |
5. How measure process concepts? | - What is an incident/event? - How measure & verify it? - How tabulate and organize data? |
6. How sample cases & events? | - sample diversity in what dimensions? - Sample size - # of events vs. cases |
7. How analyze data to develop or test your process proposition?
| Match data analysis methods To number of cases and events |
8. What are the threats to study validity? | - process pattern observed? - replicable methods? - reliable measurements? - story verisimilitude? |
EXTRA SLIDES IF QUESTIONS ARISE�
(Source: Hibbert & Wilkinson, 1994, pp. 218)
(Source: Hibbert & Wilkinson, 1994, pp. 218)
Lyanupov Exponent
Correlation Dimension
Brock, Dechert & Scheinkman�(BDS) Statistic
Different Colors of Random Processes
Self-Organized Criticality
Per Bak, “How Nature Works,” 1996
I II III IV
100 % Deterministic
100 % Stochastic
Mathematics
10
100
1000
Dimension - Physics
I. Solvable dynamic system, e.g. gear trains, physical pendulum
II. Amenable to perturbation theory, e.g. satellite orbits
III. Chaotic dynamic systems, e.g. climatology, Lorenz equations
IV. Turbulent/stochastic systems, e.g. quantum mechanics, turb. flow
(Source: Morrison, 1991)
Three-Dimensional
Representation of
Action and Outcome
Events Over Time
In the Development
Of Cochlear Implant
Innovation
# Dimensions
œ
0
Time
Gestation Startup Begin Development End Development Implementation
Random
Chaotic
Periodic
Fixed Point
5
Random, Chaotic, and Periodic Dimensions
in the Innovation Journey
Cycle 1:
Independent Company
Startups
Cycle 2:
Qnetics Merger
Cycle 3:
Load Management
Device
MICRO QNETICS ACTION AND OUTCOME EVENTS
Cycling the Innovation Journey
Divergent Behavior
Convergent Behavior
Enabling Factors
Constraining Factors