In an important and provocative paper, `Does Compulsory School Attendance Affect Schooling and Earnings?', Angrist and Krueger use quarter of birth as an instrument for educational attainment in wage equations. To support a causal interpretation of their estimates, they argue that compulsory...

Several recent studies use the schooling and wage variation between monozygotic twins to estimate the return to schooling. In this paper, we summarize the results from this literature, and we examine the implications of endogenous determination of which twin goes to school longer and of...

In an important and provocative paper, `Does Compulsory School Attendance Affect Schooling and Earnings?', Angrist and Krueger use quarter of birth as an instrument for educational attainment in wage equations. To support a causal interpretation of their estimates, they argue that compulsory...

Investigators of social differentials in health outcomes commonly augment incomplete micro data by appending socioeconomic characteristics of residential areas (such as median income in a zip code) to proxy for individual characteristics. However, little empirical attention has been paid to how...