Individual skill

did

Design, estimate, validate, and write up a difference-in-differences analysis, using the post-2018 heterogeneity-robust toolkit with an explicit statement of which parallel-trends assumption is imposed. TRIGGER on "difference-in-differences", "DiD", "TWFE", "event study", "staggered adoption", "staggered rollout", "parallel trends", "pre-trends", "Callaway-Sant'Anna", "Sun-Abraham", "imputation estimator", "Goodman-Bacon", "stacked DiD", "not-yet-treated", "repeated cross-section", "HonestDiD", "triple differences", "Poisson DiD", "nonlinear DiD", or any panel or repeated-cross-section setting where units become treated over time (policy rollout, staggered feature launch, state law changes). One or a few treated aggregate units: synthetic-control. No design chosen yet: causal-design.

skills/did/SKILL.md

Source commit 760aa99b8b270a01a2c6b0aac4e28132a9bea11e

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Observed behavior

Instructions only

Last checked

Nov 7, 2026

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