RPIV - Residual Prediction Tests for Well-Specification of Instrumental
Variable Models
Two tests for the well-specification of the linear
instrumental variable model. The first test is based on trying
to predict the residuals of a two-stage least-squares
regression using a random forest. The second test is robust to
weak-identification and based on trying to predict the
residuals for a particular candidate parameter and can also be
used to construct confidence sets with an Anderson-Rubin-type
inversion. Details can be found in Scheidegger, Londschien and
Bühlmann (2025) "Machine-learning-powered specification testing
in linear instrumental variable models"
<doi:10.48550/arXiv.2506.12771>.