Self-Selection and Student Achievement

Students in any schools are not a random collection from the population. They become schoolmates because of their parents' selections of school quality that are contingent on their genetic abilities and family background. Even specified correctly, the conventional educational production functions cannot be used to find the effects of school inputs or quality. Therefore, the weak or zero relationship between school inputs and student achievement widely documented in the literature by no means implies that school inputs or quality does not matter. Further, since students enter schools by self-selection, any observed differences in student achievement between public and private schools do not necessarily mean that these schools have any differences in the effectiveness of operation.