of the associated IV results. We discuss potential adjustments to IV estimates in the presence of this bias …

Empirical researchers routinely encounter sample selection bias whereby 1) the regressor of interest is assumed to be …

This paper considers causal inference and sample selection bias in non-experimental settings in which: (i) few units in … treated units and, hence, in alleviating the bias due to systematic differences between the treated and comparison units …

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 …

effect having an opposite sign from the true effect. We present an expression for the asymptotic bias of both OLS and IV … estimators and discuss the conditions under which sign reversal may occur. We provide a method for eliminating this bias when …