Abstracts - Earli

schooling). A combination of both approaches yields an estimate of this absolute effect and itsvariation between teachers and schools. The research findings presented in this article illustratehow the "value added" of schooling can be assessed empirically using cross-sectional data.Application of the regression-discontinuity approach within a multilevel framework produces bothan estimate of the absolute effect of one year schooling and an estimate of the variation acrossschools of this effect. In the study reported here the approach was applied to both a cross-sectionaland a longitudinal data set. The research findings are very similar for both data sets.The contribution of schooling to the cognitive development of secondary education students inCyprus: an application of regression-discontinuity with multiple cut-off pointsLeonidas Kyriakides, University of Cyprus, CyprusHans Luyten, University of Twente, NetherlandsThis article reports the results of a study in which the basic regression-discontinuity approach isextended. A model with multiple cut-off points is fitted. In addition the paper investigates theextent to which the measure of the effect of schooling depends on the criteria used for measuringschool outcomes. Specifically, the paper presents the results of a study which examines the effectof schooling on secondary student development of five domains of reasoning (i.e., categorical,quantitative, spatial, causal, and propositional). The Comprehensive Test of CognitiveDevelopment was administered to students of the six grade groups of secondary schools and adesign with multiple cut-off points was applied. Data on mathematics and language achievementin curriculum-based tests were also used to measure the effect of schooling. Finally, implicationsof findings for the development of educational effectiveness research are drawn.A seasonal perspective on school effectiveness: Evidence from a Flemish longitudinal study inkindergarten and first gradePieter Verachtert, Catholic University of Leuven, BelgiumJan Van Damme, Catholic University of Leuven, BelgiumPatrick Onghena, Catholic University of Leuven, BelgiumPol Ghesquiere, Catholic University of Leuven, BelgiumSince the seminal work of Barbara Heyns (1978), a limited number of studies have attempted toassess the unique contribution of schooling to children’s cognitive achievement by comparing theirlearning rates during the school year and the summer vacation. These studies invariably foundsignificantly faster learning rates during the school year as compared to the summer, therebyadding to the evidence of an absolute effect of schooling. Whereas most of these studies indicatethat schooling has an attenuating effect on the growth of the achievement gaps between differentsocioeconomic groups, there is considerably less consensus on the effect of schooling on other(e.g. racial/ethnic) achievement gaps. In this study, we use multilevel piecewise growth curvemodelling to analyse growth in mathematical skills throughout kindergarten and first grade in asample of more than 3500 Flemish children. First, the learning rates during the school year arecompared with the learning rates during the summer. Second, we investigate whether schoolinghas a positive effect on the achievement gaps between children from different socioeconomic,racial/ethnic and linguistic backgrounds. Third, we examine to which extent differences betweenschools in learning rates during the school year and during the summer can be accounted for byschool characteristics such as group composition.– 520 –