Home > Publications . Search All . Browse All . Country . Browse PSC Pubs . PSC Report Series

PSC In The News

RSS Feed icon

Sastry's 10-year study of New Orleans Katrina evacuees shows demographic differences between returning and nonreturning

Stafford says less educated, smaller investors more likely to sell off stock and lock in losses during market downturn

Chen says job fit, job happiness can be achieved over time

Highlights

Deirdre Bloome wins ASA award for work on racial inequality and intergenerational transmission

Bob Willis awarded 2015 Jacob Mincer Award for Lifetime Contributions to the Field of Labor Economics

David Lam is new director of Institute for Social Research

Elizabeth Bruch wins Robert Merton Prize for paper in analytic sociology

Next Brown Bag

Monday, Oct 12
Joe Grengs, Policy & Planning for Social Equity in Transportation

Interaction Terms in Nonlinear Models

Publication Abstract

Karaca-Mandic, P., Edward Norton, and B. Dowd. 2012. "Interaction Terms in Nonlinear Models." Health Services Research, 47(1): 255-274.

Objectives. To explain the use of interaction terms in nonlinear models. Study Design. We discuss the motivation for including interaction terms in multivariate analyses. We then explain how the straightforward interpretation of interaction terms in linear models changes in nonlinear models, using graphs and equations. We extend the basic results from logit and probit to difference-in-differences models, models with higher powers of explanatory variables, other nonlinear models (including log transformation and ordered models), and panel data models. Empirical Application. We show how to calculate and interpret interaction effects using a publicly available Stata data set with a binary outcome. Stata 11 has added several features which make those calculations easier. LIMDEP code also is provided. Conclusions. It is important to understand why interaction terms are included in nonlinear models in order to be clear about their substantive interpretation.

DOI:10.1111/j.1475-6773.2011.01314.x (Full Text)

Browse | Search : All Pubs | Next