Notes on Regression Discontinuity Methods - [athena.sas.upenn ...

Two Types of Designs
• Sharp Regression Discontinuity (SRD) Design
Wi = 1{Xi ≥ c} (1)
All individuals with covariates of c or greater are assigned to
treatment.
• We can use the discontinuity in the conditional expectation of
the outcome given the covariate to uncover an average causal
effect of treatment
τSRD = limx↓cE(Yi|Xi = x) − limx↑cE(Yi|Xi = x) (2)