NEPS technical report for mathematics: Scaling results of Starting Cohort 1 for eight-year-old children (wave 9)

The National Educational Panel Study (NEPS) aims at investigating the development of competencies across the whole life span and designs tests for assessing these different competence domains. To evaluate the quality of the competence tests, a wide range of analyses based on item response theory (IRT) were performed. This paper describes the data and scaling procedure for the mathematical competence test for 8-year-old children of starting cohort 1 (newborns). The mathematics test consists of 20 items that represent different content areas as well as different cognitive components and use different response formats. The test was administered to 1,632 students. A partial-credit model was used for scaling the data. Item fit statistics, differential item functioning, Rasch-homogeneity, and the test ́s dimensionality were evaluated to ensure the quality of the test. The results show that the test exhibited a good reliability (EAP/PV reliability = .76) and that the items satisfactorily fitted the model. Furthermore, comparable measurements could be confirmed for different subgroups. Limitations of the test were some recognizable gaps at the upper end of the scale’s item difficulties. Overall, the results revealed good psychometric properties of the mathematics test, thus supporting the estimation of a reliable mathematics competence score. Besides the scaling results, this paper also describes the data available in the Scientific Use File and provides the R syntax for scaling the data.