Developmental changes in students' use of dimensional comparisons to form ability self‐concepts in math and verbal domains

Dimensional comparisons (i.e., comparing own performances across domains) may drive an increasing differentiation in students' math and verbal self‐concepts over time, but little longitudinal research has directly tested this assumption. Using cross‐sequential data spanning Grades 1–12 (N = 1069, ages 6–18, 92% White, 2% Black, 51% female, collected 1987–1996), this study charted age‐related changes in the role of dimensional comparisons in students' ability self‐concept formation. It used three types of self‐concept measures: peer comparisons, cross‐domain comparisons, and no comparisons. Results indicated that the increase in students' use of dimensional comparisons in self‐evaluations substantially contributed to the increasing differentiation in students' math and verbal self‐concepts over time. Findings highlight the importance of dimensional comparisons in the development of students' ability self‐concepts.