We use a natural experiment to show that the presence of an external examiner has both a direct and an indirect negative effect on the performance of monitored classes in standardized educational tests. The direct effect is the difference in the test performance between classes of the same school with and without external examiners. The indirect…

Education policy in the U.S. in the last two decades has emphasized large-scale assessment of students, with growing consequences for schools, teachers, and students. Given the high stakes of such tests, it is important to understand the relationships between students' answers to test items and their knowledge and skills in the tested content…