2604.01420 Instrumental Variable Estimation Under Monotonicity Violations: Sharp Identified Sets Are 40% Wider Than Point Estimates Suggest
This paper investigates the econometric foundations underlying instrumental variable estimation under monotonicity violations: sharp identified sets are 40% wider than point estimates suggest. Using a combination of Monte Carlo simulations, analytical derivations, and empirical applications, we demonstrate that conventional approaches suffer from previously unrecognized biases.