On Muddled Reasoning and Mediation Modeling

Abstract

The hope of mediation modeling is that psychologists can go beyond tests of association to truly uncover mechanisms of change. We argue this hope can be realized only if psychologists make important distinctions regarding causality and inference. From the perspective of Aristotelian philosophy, mediation models are sequences of efficient causes, and psychologists should therefore seek to identify those persons who can be traced through the entire sequence successfully. By reanalyzing data from two mediation studies we demonstrate that contemporary, aggregate methods of analysis are not suitable for this task because they are instead focused on making inferences about population parameters. In both studies alternative, person-centered methods revealed that majorities of participants were not traceable through the statistically significant mediation models.