Comparing apples with oranges? An approach to link TIMSS and the National Educational Panel Study in Germany via equipercentile and IRT methods

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The aim of this linking study is to classify the National Educational Panel Study (NEPS) according to the criterion based reference frame of the Trends in International Mathematics and Science Study (TIMSS). One requirement for a strong linking is a high conceptual overlap of the frameworks. The results of the comparison between NEPS and TIMSS indicate a high overlap. To link the studies the equipercentile equating and an IRT linking approach are compared. The results show that both methods showed similar descriptive statistics and satisfying classification consistency. Nevertheless, the equipercentile equating has small advantages and is therefore more suitable. Thus, inferences are possible on a population level, but the results should not be reported or interpreted on an individual level.
Original languageEnglish
JournalStudies in Educational Evaluation
Pages (from-to)58–67
Number of pages10
Publication statusPublished - 01.12.2015

Bibliographical note

Funding Information:
The project was funded by the Centre for International Student Assessment (ZIB) and the Federal Ministry of Education and Research (BMBF) in Germany. The authors would like to thank the ZIB and BMBF for their support.

Publisher Copyright:
© 2015 Elsevier Ltd.

    Research areas

  • Empirical education research - Equating methods, Large scale assessment, Linking study, Mathematics competencies, Student assessment, TIMSS