%0 Generic %A Kitagawa, T %C London, UK %D 2013 %F discovery:10128117 %I Centre for microdata methods and practice (cemmap) %N 53/13 %T A bootstrap test for instrument validity in heterogeneous treatment effect models %U https://discovery.ucl.ac.uk/id/eprint/10128117/ %X This paper develops a specification test for the instrument validity conditions in the heterogeneous treatment effect model with a binary treatment and a discrete instrument. A necessary testable implication for the joint restriction of instrument exogeneity and instrument monotonicity is given by nonnegativity of point-identifiable complier’s outcome densities. Our specification test infers this testable implication using a Kolmogorov-Smirnov type test statistic. We provide a bootstrap algorithm to implement the proposed test and show its asymptotic validity. The proposed test procedure can apply to both discrete and continuous outcome cases. %Z This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions.