This post delves into a disagreement I have with three prominent political scientists, Jens Hainmueller, Jonathan Mummolo, and Yiqing Xu (HMX), on a fundamental methodological question: how to analyze interactions in observational data? In 2019, HMX proposed the "binning estimator" for studying interactions, a technique that is now commonly used by political scientists. I argued…
Category: Interactions
[80] Interaction Effects Need Interaction Controls
In a recent referee report I argued something I have argued in several reports before: if the effect of interest in a regression is an interaction, the control variables addressing possible confounds should be interactions as well. In this post I explain that argument using as a working example a 2011 QJE paper (.htm) that…
[57] Interactions in Logit Regressions: Why Positive May Mean Negative
Of all economics papers published this century, the 10th most cited appeared in Economics Letters , a journal with an impact factor of 0.5. It makes an inconvenient and counterintuitive point: the sign of the estimate (b̂) of an interaction in a logit/probit regression, need not correspond to the sign of its effect on the…
[17] No-way Interactions
This post shares a shocking and counterintuitive fact about studies looking at interactions where effects are predicted to get smaller (attenuated interactions). I needed a working example and went with Fritz Strack et al.’s (1988, .html) famous paper [933 Google cites], in which participants rated cartoons as funnier if they saw them while holding a…