causal

Introduction to the Synthetic Control Method in Python with mlsynth

Learn the synthetic control method and the mlsynth library in Python with the Proposition 99 tobacco case. The tutorial builds a synthetic California from five donor states and reads its weights and predictor balance. It tests the result with in-space and in-time placebos and leave-one-out refits, replicates the Stata edition, and compares four mlsynth estimators.

The FWL Theorem: Making Multivariate Regressions Intuitive

Understanding the Frisch-Waugh-Lovell theorem to isolate causal relationships by partialling-out confounders in a simulated fast-food coupon promotion, with an appendix that extends FWL to panel data

scspill

Did a policy really work if it also affected the comparison regions? scspill, a Python package, estimates both the true effect and the spillover to them.

Covariates in Difference-in-Differences: The LaLonde Test in Python

Reproducing Scott Cunningham's LaLonde test in Python — covariates rescue a difference-in-differences ATT only when they enter the control group's counterfactual trend, recovering the $1,794 experimental benchmark from a naive $3,621.

Do Industrial Parks Work? Evaluating Place-Based Policy in Ethiopia with Difference-in-Differences

Do industrial parks raise local economic activity — and for whom? A beginner's staggered difference-in-differences evaluation of Ethiopian industrial parks in Python, replicating Huang, Wang & Xu (2026) on synthetic calibrated data: TWFE and an event study with pyfixest, the modern Sun-Abraham, Borusyak/Gardner and Callaway-Sant'Anna estimators plus a Goodman-Bacon decomposition with diff-diff, survey-weighted repeated-cross-section DiD on DHS household welfare and women's empowerment, and Conley spatial standard errors.

Bouncing Back Better? Evaluating the Economic Impact of the Aceh Tsunami

How did the 2004 tsunami affect the economy of Aceh, Indonesia, over the long run? This beginner-friendly Python tutorial uses simulated data, nighttime lights, and several causal methods to compare damaged and undamaged areas before and after the disaster.

Staggered Synthetic Difference-in-Differences (SDID) in Stata: Gender Quotas and Women in Parliament

Extend synthetic difference-in-differences to staggered adoption, where units adopt treatment at different times, and apply it in Stata to parliamentary gender quotas across 119 countries — deriving the per-cohort estimator, its aggregation into the overall ATT, the modern sdid_event event study, and bootstrap, jackknife, and placebo inference.

Synthetic Difference-in-Differences (SDID) in Stata: Re-evaluating California's Proposition 99

Introduce and derive synthetic difference-in-differences, then apply it to California's Proposition 99 — comparing SDID with the original difference-in-differences and synthetic control (synth2), and how to run placebo inference with a single treated unit.

Double LASSO in Python: Does Abortion Reduce Crime?

Python companion to the R and Stata Double LASSO tutorials — same data, same five estimators, plus a hands-on introduction to the DoubleML library (DoubleMLPLR, DoubleMLIRM, and learner-robustness across LASSO, RandomForest, XGBoost).

Double LASSO in Stata: Does Abortion Reduce Crime?

Stata companion to the R Double LASSO tutorial — same data, same five estimators, replicating the Belloni-Chernozhukov-Hansen 284-control extension of Donohue and Levitt's abortion-and-crime panel with pdslasso, rlasso, and cvlasso.