A longitudinal test of the internal/external frame of reference model

The internal/external frame of reference (I/E) model by Marsh assumes two c entral information sources for the constitution of domain-specific academic self-concepts: (1) Serial comparisons (external frame of reference), in wh ich students compare their own achievements with those of their classmates, and (2) intraindividual (dimensional) comparisons (internal frame of refer ence), in which students compare their own achievement in one subject with those in other subjects. Empirical support for this model is mainly provide d by cross-sectional studies, which are not fully appropriate to investigat e the influence of the frame of reference on changes in self-concept variab les. Therefore, we analyzed data from a subsample of a German longitudinal study. Participants were n = 1754 7th graders. Analyses on the basis of str uctural equation modeling and hierarchical linear modeling supported the va lidity of the I/E model with respect to changes in academic self-concept va riables that are more or less independent of the academic environment.