The intercept in endogenous selection models is of fundamental importance for the evaluationof average treatment effects. While various intercept estimators for additive linear selectionmodels exist, there are currently no estimators for nonlinear selection models. This paper introduces...

We propose various semiparametric estimators for nonlinear selection models, where slope and intercept can be separately identifed. When the selection equation satisfies a monotonic index restriction, we suggest a local polynomial estimator, using only observations for which the marginal...