  Ethnic achievement gaps are often explained in terms of student and school
factors. The decomposition of these gaps into their within- and between-school
components has therefore been applied as a strategy to quantify the overall
influence of each set of factors. Three competing approaches have previously
been proposed, but each is limited to the study of student-school
decompositions of the gap between two ethnic groups (e.g., White and Black).
The authors show that these approaches can be reformulated as mediation models
facilitating new extensions to allow additional levels in the school system
(e.g., classrooms, school districts, geographic areas) and multiple ethnic
groups (e.g., White, Black, Hispanic, Asian). The authors illustrate these
extensions using administrative data for high school students in Colombia and
highlight the increased substantive insights and nuanced policy implications
they afford.
