The Internal/External Frame of Reference Model of Self-Concept and Achievement Relations: Age-Cohort and Cross-Cultural Differences Herbert W. Marsh Australian Catholic University King Saud University University of Oxford Adel Salah Abduljabbar King Saud University Philip D. Parker Alexandre J. S. Morin Australian Catholic University Faisal Abdelfattah Qatar University Benjamin Nagengast University of Tu ¨ bingen Jens Mo ¨ller University of Kiel Maher M. Abu-Hilal Sultan Qaboos University The internal/external frame of reference (I/E) model and dimensional com- parison theory posit paradoxical relations between achievement (ACH) and self-concept (SC) in mathematics (M) and verbal (V) domains; ACH in each domain positively affects SC in the matching domain (e.g., MACH to MSC) but negatively in the nonmatching domain (e.g., MACH to VSC). This substantive-methodological synergy based on latent variable models of Trends in International Mathematics and Science Study (TIMSS) data sup- ports the generalizability of these predictions in relation to: mathematics and science domains, intrinsic motivation as well as self-concept, and age and nationality, based on nationally representative matched samples of fourth- and eighth-grade students from three Middle Eastern Islamic, five Western, and four Asian countries (N=117,321 students) with important theoretical, developmental, cross-cultural, and methodological implications. American Educational Research Journal February 2015, Vol. 52, No. 1, pp. 168–202 DOI: 10.3102/0002831214549453 Ó 2014 AERA-. http://aerj.aera.net at Sultan Qaboos University on February 8, 2015 http://aerj.aera.net Downloaded from