We analyse the PISA-reported convergence in the performance of private and public schools in Portugal. When PISA sampling weights are used, the number of students enrolled in those types of schools and specific grades/tracks of study differs significantly from official population figures. To account for those differences, we apply a…

Background: Test score comparability in international large-scale assessments (LSAs) is greatly important to ensure test fairness. To effectively compare test scores on an international scale, score linking is widely used to convert raw scores from different linguistic version of test forms into a common score scale. An example is the multigroup…