A Validation Study of the Extended Relevance Scale using the D3mirt Package for R

Abstract

ABSTRACT This paper reports a validation study based on descriptive multidimensional item response theory (DMIRT), implemented in the R package D3mirt by using the ERS-C, an extended version of the Relevance subscale from the Moral Foundations Questionnaire including two new items for collectivism (17 items in total). Two latent models are created and investigated in two large samples (N = 1560 and N = 1380 US citizens). The internal investigation indicates a presence of two unidimensions, Compassion and Conformity, and a third within-multidimension of Collectivism in both samples. The external investigation show that Republicans are the highest on Conformity in the models, followed by Independents, and lastly Democrats. Democratic followers are the highest on compassion, followed by Independents and Republicans. No difference between groups on Collectivism were found. Lastly, the models succeeded in correctly identifying the Republican and Democratic voters but struggled to correctly classify the Independent.