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Learning Coach
Recommended for first-time learners
Your step-by-step guide through causal inference. Starts with intuition before introducing formulas,
breaks concepts into manageable pieces, and provides worked examples using chapter datasets. Checks
your understanding at each stage and guides you to answers with positive reinforcement. Covers all
6 chapters: RCTs, Regression, IV, RD, DD, and the Wages of Schooling.
Step-by-Step
Worked Examples
Comprehension Checks
Homework Help
Beginner Friendly
Try: "Walk me through the RAND Health Insurance Experiment from Chapter 1 step by step"
Best for: Building intuition chapter by chapter, getting unstuck on homework problems
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Case-Study Explainer
For understanding the stories behind the data
The domain expert who brings each natural experiment to life. Uses a Context-Design-Identification-Policy
framework to explain the historical circumstances, institutional details, and policy features that make
each study's causal strategy work. Covers 11 case studies including the RAND HIE, Oregon Health Lottery,
MDVE, KIPP schools, MLDA mortality, and Great Depression banking.
Historical Context
Policy Analysis
11 Case Studies
Identification Strategy
Try: "Explain the institutional context behind the Oregon Health Plan lottery from Chapter 1"
Best for: Understanding why each causal method works in its real-world setting, preparing policy discussions
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Exam Coach
For midterm and final preparation
Your test-preparation specialist. Starts with diagnostic questions to find your weak spots, then builds
targeted practice sets with increasing difficulty. Drills the distinctions between IV, RD, and DD,
provides flashcard-style concept summaries, and flags common exam pitfalls. Question formats include
multiple choice, short answer, Wald estimator calculations, and scenario-based problems.
Practice Questions
Weak Spot Diagnosis
Method Distinctions
Flashcard Summaries
Increasing Difficulty
Try: "Quiz me on the difference between IV and RD for Chapters 3 and 4"
Best for: Drilling key concepts before exams, identifying gaps in your understanding of the 5 causal methods
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Socratic Challenger
For students with some foundation
Teaches through probing questions, never direct answers. Challenges your assumptions about correlation
and causation, pushes you to identify validity threats, and asks the hard questions: ‘Why can’t
we just compare?’, ‘What assumption does the heavy lifting?’, ‘Who are the
compliers?’ Gives direct help after 3 rounds if you’re stuck, or immediately for Python syntax.
Questions Only
Assumption Challenges
Validity Threats
Deep Thinking
Critical Reasoning
Try: "I think comparing average outcomes between treated and control groups always gives a causal effect"
Best for: Developing critical thinking about identification, preparing to defend research design choices
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Code-First Experimenter
For hands-on, learn-by-doing coders
Starts with Python code and real data, then builds up to theory. Shows you the result first and explains
why it works. Encourages ‘What if’ experiments: change the bandwidth, drop control variables,
compare OLS to IV. Uses pandas and pyfixest with all course datasets streamed from GitHub.
Python Code
Real Datasets
What-If Experiments
pyfixest
Google Colab Ready
Try: "Show me IV estimation of returns to schooling using quarter-of-birth data from Chapter 6"
Best for: Learning causal methods through code, extending chapter notebooks with your own experiments
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