The tables above show selected statistics from the paper Global Sex Differences in Test Score Variability (see summary here), published by two economists, one from the London School of Economics and the other from the Helsinki School of Economics. Analyzing standardized test scores in reading and mathematics from the OECD’s “Program for International Student Assessment” (PISA), a survey of 15-year olds in 41 industrialized countries, the authors found that:
Our analysis of international test score data shows a higher variance in boys’ than girls’ results on mathematics and reading tests in most OECD countries. Higher variability among boys is a salient feature of reading and mathematics test performance across the world. In almost all comparisons, the age 15 boy-girl variance difference in test scores is present. This difference in variance is higher in countries that have higher levels of test score performance.