https://ninonmoreaukastler.com
1. Estimate FE on untreated units
2. Predict counterfactual outcomes for treated
3. Compute average effect in levels
4. Scale by average counterfactual outcome
Matches RoR interpretation; generalizes 2×2 PPML.
Event study simulation:
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1. Estimate FE on untreated units
2. Predict counterfactual outcomes for treated
3. Compute average effect in levels
4. Scale by average counterfactual outcome
Matches RoR interpretation; generalizes 2×2 PPML.
Event study simulation:
8/
In a simple example (N=2, T=3), I show that TWFE PPML is biased (similarly to TWFE OLS). It "downscales" treatment effects, analog to the negative weights problem.
4/
In a simple example (N=2, T=3), I show that TWFE PPML is biased (similarly to TWFE OLS). It "downscales" treatment effects, analog to the negative weights problem.
4/