Using Mixed-Model Item Response Theory to Analyze Organizational Survey Responses: An Illustration Using the Job Descriptive Index

In this article, the authors illustrate the use of mixed-model item response theory (MM-IRT) and explain its usefulness for analyzing organizational surveys. The authors begin by giving an overview of MM-IRT, focusing on both technical aspects and previous organizational applications. Guidance is provided on how researchers can use MM-IRT to check scoring assumptions, identify the influence of systematic responding that is unrelated to item content (i.e., response sets), and evaluate individual and group difference variables as predictors of class membership. After summarizing the current body of research using MM-IRT to address problems relevant to organizational researchers, the authors present an illustration of the use of MM-IRT with the Job Descriptive Index (JDI), focusing on the use of the "?'' response option. Three classes emerged, one most likely to respond in the positive direction, one most likely to respond in the negative direction, and another most likely to use the "?'' response. Trust in management, job tenure, age, race, and sex were considered as correlates of class membership. Results are discussed in terms of the applicability of MM-IRT and future research endeavors.