Research on subjective wellbeing typically assumes that responses to survey questions are comparable across respondents and across time. However, if this assumption is violated, standard methods in empirical research may mislead. I address this concern with three contributions. First, I give a...

Measurement invariance is a fundamental assumption in item response theory models, where the relationship between a latent construct (ability) and observed item responses is of interest. Violation of this assumption would render the scale misinterpreted or cause systematic bias against certain...

Measurement invariance is a fundamental assumption in item response theory models, where the relationship between a latent construct (ability) and observed item responses is of interest. Violation of this assumption would render the scale misinterpreted or cause systematic bias against certain...