Leistungstestwerte als Validierungskriterium von Schullaufbahnempfehlungen: Ein neuer formaler Ansatz

In this paper, an approach of validating school placement decisions is presented and ap­plied to a representative sample of N = 2 300 Luxembourgish 9th graders. In this approach, the vali­dation criterion “keeping the track” was supplemented by a criterion based on scores of standardized scholastic aptitude tests. For this purpose, students’ test scores were allocated to either of two catego­ries. These categories were separated by the test score that represented the intersection of the distribu­tions of test scores of students from either the vocational track or the academic track of Luxembour­gish secondary school. Students of the vocational track were considered as being misclassified if their test score was above the intersection test score, students of the academic track were considered as being misclassified if their test score was below the intersection test score. According to this classifi­cation rule, about 21 % of all students were misclassified. Predictive validity was estimated by the degree of agreement between school placement decisions and test categories and between school placement decisions and actual tracks, with the latter being higher than the former. The results ob­tained were discussed as indicators of both a lack of permeability of the Luxembourgish school sys­tem and placement decisions being only partially based on students’ performance.