Cross-cultural differences in the use of the "?" Response category of the Job Descriptive Index: An application of the item response tree model

Historically, the "?" response category (i.e., the question mark response category) has been criticized because of the ambiguity of its interpretation. Previous empirical studies of the appropriateness of the "?" response category have generally used methods that cannot disentangle the response style from target psychological traits and have also exclusively focused on Western samples. To further develop our understanding of the "?" response category, we examined the differing use of the "?" response category in the Job Descriptive Index (JDI) between U.S. and Korean samples by using the recently proposed item response tree (IRTree) models. Our research showed that the Korean group more strongly prefers the "?" response category, while the U.S. group more strongly prefers the directional response category (i.e., Yes). In addition, the Korean group tended to interpret the "?" response category as mild agreement, while the U.S. group tended to interpret it as mild disagreement. Our study adds to the scientific body of knowledge on the "?" response category in a cross-cultural context. We hope that our findings presented herein provide valuable insights for researchers and practitioners who want to better understand the "?" response category and develop various psychological assessments in cross-cultural settings.