Estimating the true effect of class size on student performance requires a strategy that looks only at variations in class size that are unrelated to students» previous achievement. (educationnext.org)
In four of the countries, Australia, Hong Kong, Scotland, and the United States, the standard error of the estimated effects of class size was extremely large, indicating that little confidence should be placed in the results. (educationnext.org)
The cloud hovering over the comparison between voucher and class - size research is not the intervening effect of class size on our findings, but rather the possible bias in Krueger's own estimates. (educationnext.org)