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arXiv · 2503.13323

Difference-in-Differences Designs: A Practitioner's Guide

Andrew Baker·Brantly Callaway·Scott Cunningham·Andrew Goodman-Bacon·Pedro H. C. Sant'Anna
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Abstract

Difference-in-differences (DiD) is arguably the most popular quasi-experimental research design. Its canonical form, with two groups and two periods, is well-understood. However, empirical practices can be ad hoc when researchers go beyond that simple case. This article provides an organizing framework for discussing different types of DiD designs and their associated DiD estimators. It discusses covariates, weights, handling multiple periods, and staggered treatments. The organizational framework, however, applies to other extensions of DiD methods as well.

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Andrew Baker, Brantly Callaway, Scott Cunningham, Andrew Goodman-Bacon, Pedro H. C. Sant'Anna. 2025-03-17. Difference-in-Differences Designs: A Practitioner's Guide. https://arxiv.org/abs/2503.13323

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