Introducing Item Pool Visualization: A method for investigation of concepts in self-reports and psychometric tests

Abstract

In this article, we introduce Item Pool Visualization. It is an illustration system that locates items and item pools (scales) from multiple psychological instruments regarding their commonality and distinguishability along several dimensions of nested radar charts. The application of Item Pool Visualization creates illustrations that represent different item pools by different circles that do not overlap. Item Pool Visualization illustrates a comparison of different structural equation models that are estimated with the same data. It combines the advantages of general and correlated factor models when evaluating psychological instruments. Furthermore, in contrast to other visualization methods, Item Pool Visualization provides an empirically driven categorization of psychological constructs and their subconcepts (facets) that is suited to provide professionals with help in comparing psychometric constructs, questionnaires, and selecting tests.