Education Commons^™

Alternative Scaling Models And Dependencies In Pisa, Greg Macaskill

OECD Programme for International Student Assessment (PISA)

This paper examines trends between PISA 2003 and PISA 2006 for the reading and mathematics scales for the OECD countries using both the standard one parameter (1PL) model that has been used in published OECD reports, and a generalised partial credit model, as implemented in ACER ConQuest, which estimates optimal values for each possible score on an item.