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Tessera: Discretizing Data Analysis Workflows on a Task Level

Jing Nathan Yan Ziwei Gu Jeffrey M. Rzeszotarski

Cornell University

jy858@cornell.edu

zg48@cornell.edu

jeffrz@cornell.edu

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Exploratory Visual Analysis(EVA) is NOT EASY

Massive Data

Data analysts

…and tracking the process can be even harder!

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SESSION

Goal1

Goal2

Subgoal

Subgoal

Subgoal

e1

e2

e3

e4

…….

ek

e5

How do we map log events to (sub)-goals?

Filter Year>= “2000”, Count number of movies, plot histograms of Counts setting X-axis=distributor.

e1

Task-level analyses of log data reveal useful insights, but logs are complex, heterogenous, and large in scale

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Our new approach, Tessera, employs data, cognitive and temporal features to discretize analyst log data

Filter Year>= “2000”, Count number of movies, plot histograms of Counts setting X-axis=distributor.

e1

e2

e3

e4

e1

en

…….

ek

….

e5

SIMILARITY

Session Event Log

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Filter Year>= “2000”, Count number of movies, plot histograms of Counts setting X-axis=distributor.

e1

e2

e3

e4

e1

en

…….

ek

….

e5

SIMILARITY

Our new approach, Tessera, employs data, cognitive and temporal features to discretize analyst log data

Session Event Log

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Tessera outperformed two competing approaches in two different datasets gathered from think-aloud sessions

In cases where users were analyzing both small and large datasets, Tessera was able to identify meaningful segments of user-directed activity.

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Contributions

Tessera Framework

Abstract EVA event logs into goal-directed segments

Combine data transformation, cognitive and temporal features

Robust to different datasets and parameters settings.

A New Benchmark dataset

A new dataset combining think-aloud reports from participants

Contains more EVA operations and recruited more participants

Larger and collected through a more commonly used EVA platform.