Understanding sources of performance bias in science assessment provides important insights into whether science curricula and/or assessments are valid representations of student abilities. Research investigating assessment bias due to factors such as instrument structure, participant characteristics, and item types are well documented across a variety of disciplines. However, the relationships...

BACKGROUND: Both the clinician (IDS-C(30)) and self-report (IDS-SR(30)) versions of the 30-item Inventory of Depressive Symptomatology have acceptable psychiatric properties and have been used in various clinical studies. These two scales, however, have not been compared using item response theory (IRT) methods to determine whether the standard scoring methods are optimal. METHODS: Data were de...

Time spent in leisure is not a minor research question as it is acknowledged as a key aspect of one’s quality of life. The primary aim of this article is to qualify time and Internet use of Italian Generation Y beyond media hype and assumptions. To this aim, we apply a multidimensional extension of Item Response Theory models to the Italian “Multipurpose survey on households: aspects of daily l...

This article highlights the theoretical differences between the Likert and Thurstone approaches to attitude measurement and demonstrates how such differences can lead to discrepant attitude estimates for individuals with the most extreme opinions. Both simulated data and real data on attitude toward abortion are used to demonstrate this discrepancy. The results suggest that attitude researchers...