NBER Publications by Dan-Olof Rooth

How schooling affects cognitive skills is a fundamental question for studies of human capital and labor markets. While scores on cognitive ability tests are positively associated with schooling, it has proven difficult to ascertain whether this relationship is causal. Moreover, the effect of schooling is difficult to separate from the confounding factors of age at test date, relative age within a classroom, season of birth, and cohort effects. In this paper, we exploit conditionally random variation in the assigned test date for a battery of cognitive tests which almost all 18 year-old males were required to take in preparation for military service in Sweden. Both age at test date and number of days spent in school vary randomly across individuals after flexibly controlling for date of bir...