Regression Discontinuity - Institute for Policy Research
Regression Discontinuity - Institute for Policy Research
Regression Discontinuity - Institute for Policy Research
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Power Considerations Unique to RD: Variance of<br />
Impact Estimator in RDD<br />
Var rd (α^<br />
1 ) = σ 2 (1-R rd2 )<br />
np(1-p)(1-ns-co) 2 (1-R ts2 )<br />
• All other terms are the same, except:<br />
• R ts<br />
2<br />
is the square of the correlation between<br />
treatment status and assignment variable – higher<br />
the value less power (and more co-linearity)