Interactions do not only tell us when, but can also tell us how: Testing process hypotheses by interaction
Version of Record online: 24 AUG 2010
Copyright © 2010 John Wiley & Sons, Ltd.
European Journal of Social Psychology
Volume 41, Issue 2, pages 180–190, March 2011
How to Cite
Jacoby, J. and Sassenberg, K. (2011), Interactions do not only tell us when, but can also tell us how: Testing process hypotheses by interaction. Eur. J. Soc. Psychol., 41: 180–190. doi: 10.1002/ejsp.762
- Issue online: 21 FEB 2011
- Version of Record online: 24 AUG 2010
- Manuscript Accepted: 31 MAR 2010
- Manuscript Received: 3 JUN 2009
Hypotheses about psychological processes are often tested using traditional mediation analysis. This analysis relies on measurement of a transmitting variable. Conducting this analysis has become almost synonymous with examining process hypotheses. An alternative strategy to mediation analysis (the Testing-a-Process-hypothesis-by-an-Interaction Strategy, TPIS) is illustrated here. TPIS is based on a fully experimental design whereby a hypothesized process is tested by an interaction between the hypothesized cause of an effect and a contextual variable. In the interaction term, the contextual variable allows comparison of the causal effect observed when the process is uninterrupted to the effect observed when the process is interrupted. Thus, TPIS translates a theoretical process hypothesis into a statistical interaction hypothesis that uses a fully experimental design to directly examine the hypothesized process. Copyright © 2010 John Wiley & Sons, Ltd.