A simple method for purging mediation effects. (English) Zbl 1437.62294

Summary: Mediation effects occur when an independent variable lies in the causal path of another independent variable, thereby swamping its effects. Mediation effects can impact the ability to accurately estimate some quantity of interest. A simple solution for addressing this issue is regressing the treatment variable on the mediator variable and then use the stored residuals from this bivariate specification as the new “direct” variable. This residualized purging process, which is the core of a recently released R package, purging, is detailed in this paper. The goal at present is to offer researchers and practitioners an application using both simulated and real data to introduce and demonstrate the value of the purging solution, applied via the purging package, to efficiently address mediation effects. A second order goal of the paper is to underscore the value of writing software to streamline research processes.


62J12 Generalized linear models (logistic models)
62-08 Computational methods for problems pertaining to statistics
62P25 Applications of statistics to social sciences


R; medeff; Stata; purging
Full Text: DOI


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