PISA’s worldwide education rankings are dogged by sloppy, duplicated answers

By Cathleen O'Grady. Even the most stringently controlled surveys have some degree of bad data.
The Programme for International Student Assessment (PISA) is a Big Deal. It's a study run by the OECD every three years to see which country provides the best education in reading, mathematics, and science. The results from PISA are used to set school policies and rank international schooling systems, and the results are the subject of scrutiny, self-flagellation and celebration. More...