Computing Interaction Effects and Standard Errors in Logit and Probit Models

Abstract

This paper explains why computing the marginal effect of a change in two variables is more complicated in nonlinear models than in linear models. The command inteff computes the correct marginal effect of a change in two interacted variables for a logit or probit model, as well as the correct standard errors. The inteff command graphs the interaction effect and saves the results to allow further investigation.

Keywords

st0063 inteff interaction terms logit probit nonlinear models

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