Difference-in-Differences · Policy Evaluation
Staggered Treatment Timing
When states adopt a policy in different periods, treatment timing becomes part of the design.
Page 1 of 7 · Big Picture
The big picture: Staggered Treatment Timing
What changes when units adopt at different times?
Why a policy analyst should care
When adoption occurs at different times, already-treated units can become inappropriate controls and the target effect must be indexed by group and time.
Follow the idea from the opening question to a practical decision. These are the conceptual moves this module will develop:
1 Question What changes when units adopt at different times?
2 Explore States adopt in different years
3 Formalize Event time and treatment cohorts
4 Transfer Audit staggered timing
Use the left and right arrow keys to move between pages.