It is often believed that without instrument, endogenous sample selection models are identified only if a covariate with a large support is available (see Chamberlain, 1986, and Lewbel, 2007). We propose a new identification strategy mainly based on the condition that the selection variable...

We consider the estimation of a semiparametric location-scale model subject to endogenous selection, in the absence of an instrument or a large support regressor. Identification relies on the independence between the covariates and selection, for arbitrarily large values of the outcome. In this...

This article is intended to be a practical user guide to help assess their rebates' capability to foreclose. It first discusses how firms can assess whether their practices are capable of restricting competition. It then reviews the most important issues that are open as to the way the...