Quality & Quantity

, Volume 49, Issue 5, pp 1823–1834 | Cite as

Comparing linear probability model coefficients across groups



This article offers a formal identification analysis of the problem in comparing coefficients from linear probability models (LPM) between groups. We show that differences in coefficients from these models can result not only from genuine differences in effects, but also from differences in one or more of the following three components: outcome truncation, scale parameters and distributional shape of the predictor variable. These results point to limitations in using LPM coefficients for group comparisons. We also provide Monte Carlo simulations and real examples to illustrate these limitations, and we suggest a restricted approach to using LPM coefficients in-group comparisons.


Group differences Interaction terms Linear probability model Logit Probit 


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of SociologyUniversity of CopenhagenCopenhagenDenmark
  2. 2.The Danish National Centre for social ResearchCopenhagenDenmark
  3. 3.Department of EconomicsUniversity of CopenhagenCopenhagenDenmark

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