WEIRDness abounds! Sample characteristics, restricted variance, and why they matter for international selection and assessment research

There is increasing awareness that reliance on samples from Western, Educated, Industrialized, Rich, Democratic (WEIRD) countries may have skewed our view of human phenomena. Nowhere is this more true than in international selection and assessment (ISA) research. In the present paper, we describe a way of understanding the impact of WEIRDness on ISA phenomena: restricted variance (RV). The WEIRDness problem is usually one of cross level interactions in which a country-level variable (e.g., individualism/collectivism) might moderate the relationship between two individual-level variables. RV can help to see not only where such cross level interactions might exist, but also provide a specific, mathematical reason for their existence. We use several examples from IJSA and related sources to illustrate the role of RV in ISA-based WEIRDness.