First Course Ding: Observational Adjustment (Chapters 11 To 13 And 27)

This section groups the observational-study chapters:

• Chapter 11: The Central Role of the Propensity Score
• Chapter 12: Doubly Robust ATE Estimation
• Chapter 13: ATT and Other Estimands
• Chapter 27: Mediation Analysis

These chapters use the following estimators for nuisance fits, weighting, and treatment-effect estimation:

• Logit
• BalancingWeights
• AIPW
• plain OLS or Ridge nuisance fits when needed

1 What Is Covered

• overlap diagnostics and subclassification
• entropy and quadratic balancing weights
• manual and cross-fit AIPW logic
• ATT versus ATE targeting
• Baron-Kenny mediation as a transparent pair of OLS regressions