This paper develops a test for instrument strength based on the bias of two-stage least squares (2SLS) that: (1) generalizes the Stock-Yogo (2005) and Sanderson-Windmeijer (2016) tests to be robust to …
Online FirstReview of Economic StudiesOnline 14 May 2026
This paper asks: when does two-stage least squares (TSLS) with covariates actually estimate a local average treatment effect (LATE) — a non-negatively weighted average of causal effects for compliers …