We propose using Stochastic Frontier Analysis to estimate pupils’ academic underachievement. We model underachievement as the gap between expected achievement and actual achievement, not due to a learning disability. Our data are a panel for 2,228 Belgian pupils observed over 6 years of primary education. We found that the average underachievement gap is 23.5%. That is, the average pupil does not exploit about one fourth of their potential. Gifted pupils appear to underachieve as much as non-gifted pupils. We also found that class size is a determinant of underachievement. The association between class size and underachievement is non-monotonic, with an underachievement minimum at a class size of about 20 pupils.

我们建议使用随机前沿分析来估计学生的学业成绩不佳。我们将成绩不佳建模为预期成绩和实际成绩之间的差距，而不是由于学习障碍。我们的数据是对 2,228 名比利时学生在 6 年的小学教育中观察到的一个小组。我们发现平均成绩不佳差距为 23.5%。也就是说，普通学生不会发挥他们大约四分之一的潜力。有天赋的学生的成绩似乎与没有天赋的学生一样多。我们还发现班级规模是成绩不佳的决定因素。班级规模和成绩不佳之间的关联是非单调的，班级规模约为 20 名学生时成绩不佳的最小值。