Extending the dimensional comparison theory through students’ academic effort

• Academic self-concepts are formed when students compare their academic effort between different achievement domains. • Comparisons were in the opposite direction from comparisons originating from students’ achievement. • Higher reported effort in one achievement was linked to a lower self-concept in that domain, but it made students feel more able in the other domain. • The nature of effort seemed to determine the extent to which higher effort can result in a less favorable self-evaluation. Guided by the dimensional comparison theory ( Möller & Marsh, 2013 ), this study tested the new hypothesis that students form their academic self-concepts by comparing their academic effort across different achievement domains. The hypothesis was tested using a longitudinal study following German non-academic school students from Grades 5 to 8 (N = 3,880, 46 % female). The results of latent cross-lagged panel models showed that there were dimensional comparison effects on students’ self-concept formation from their effort in mathematics and German language arts, but in the opposite direction of comparison effects from students’ achievement. Students who reported working hard in one domain showed lower self-concept in that same domain but higher self-concept in the other domain. The results highlight that students compare their perceived academic effort to judge their academic ability in the respective achievement domains, which, in turn, adds an important new ingredient of the dimensional comparison theory.