Goldsmith-Pinkham, Paul; Hull, Peter; Kolesár, Michal - National Bureau of Economic Research - 2022
treatments are conditionally randomly assigned and the controls are sufficiently flexible to avoid omitted variables bias … treatments. Thus, recent concerns about heterogeneity-induced bias in regressions leveraging potential outcome restrictions (e … contamination bias and propose a new class of efficient estimators of weighted average effects that avoid bias. In a re-analysis of …
