Disentangling the Long-term Positive Effects of School-Average SES and Negative Effects of School-Average Achievement: A Substantive-Methodological Synergy

We juxtapose compositional (positive and negative) effects of school-average achievement and school-average socioeconomic status (SES) on academic self-concept (ASC), final high-school grade-point-average, and long-term outcomes at age 26, controlling for an extensive set of background variables (gender, age, race, academic track, risk). Our study was based on doubly-latent multilevel compositional models, using a large, nationally representative longitudinal sample (16,197 Year-10 students from 751 US high schools). At the individual-student level, the effects of SES, achievement, ASC, and grade-point-average were consistently positive on long-term outcomes. However, mostly consistent with a priori predictions based on theory and prior research at the school level:School-average SES composition effects were positive for ASC, educational and occupational expectations, and attainment (but nonsignificant for grade-point-average). School-average achievement compositional effects were significantly adverse for ASC, grade-point-average, and educational and occupational expectations (but nonsignificant for final attainment). Long-term compositional effects were mediated in part by ASC and particularly gradepoint-average. Juxtaposing our research and our review of recent studies, we replicate and extend Göllner et al.'s (2018; also see Marsh, 1991) highly controversial conclusion about the advantages of schools with high school-average SES but low school-average achievement. Moreover, we demonstrate that positive school-average SES effects are distinguishable from adverse school-average achievement effects. Our results have important implications for theory and methodology, but also parents' selection of schools for their children (a substantive-methodological synergy).