Testing the one-part fractional response model against an alternative two-part model

摘要

This note proposes a generalized two-part model for fractional response variables that nests the one-part model proposed by Papke and Wooldridge (1996). Consequently, a Wald test allows to discriminate between these two competing models. A small scale Monte Carlo simulation demonstrates that the proposed Wald test is properly sized and equipped with higher power than an alternative non-nested P-test.