Quasi‐experimental Estimates of the Effect of Class Size on Achievement in Norway*
利用挪威行政数据，通过多种准实验方法估计班级规模对初中毕业成绩的影响，发现效应接近零，可排除三年内每增减一名学生导致成绩变化超过1.5%标准差的可能性。
Abstract Using a comprehensive Norwegian administrative database, we exploit independent quasi‐experimental methods to estimate the effect of class size on student achievement at the end of lower‐secondary school. Identification based on maximum class‐size rules and population variation (and variations on these methods) give very similar estimates. We cannot reject that the class‐size effect is equal to zero, and can rule out effects as small as 1.5 percent of a standard deviation for a one‐student change in class size during three consecutive years.