Songman Kang

College of Economics and Finance
Hanyang University
222 Wangsimni-ro, Seongdong-gu


NBER Working Papers and Publications

April 2018The School-Entry-Age Rule Affects Redshirting Patterns and Resulting Disparities in Achievement
with Philip J. Cook: w24492
Since, other things equal, older children do better in school, the extent and pattern of delayed entry affects observed patterns in academic performance. This paper provides three new sets of relevant findings, utilizing comprehensive data on birth cohorts of children who enrolled in first grade in North Carolina public schools.: (1) Delayed entry (redshirting) reduces the male-female achievement gap by 11%; (2) For each of 6 groups defined by sex and race/ethnicity, the likelihood of redshirting is strongly inversely related to academic ability; and (3) A recent shift in the cut date to earlier in the calendar year reduced redshirting, and provided clear evidence that parental decisions are tied to the absolute age of the child rather than age relative to classmates. The adaptation of r...
February 2013Birthdays, Schooling, and Crime: New Evidence on the Dropout-Crime Nexus
with Philip J. Cook: w18791
Based on administrative data for five cohorts of public school children in North Carolina, we demonstrate that those born just after the cut date for starting school are likely to outperform those born just before in reading and math in middle school, and are less likely to be involved in juvenile delinquency. On the other hand, those born after the cut date are more likely to drop out of high school before graduation and commit a felony offense by age 19. We also present suggestive evidence that the higher dropout rate is due to the fact that youths born after the cut date have longer exposure to the legal possibility of dropping out. The "crime" and "dropout" differences are strong but somewhat muted by the fact that youths born just before the cut date are substantially more likely t...

Published: Cook, Philip J., and Songman Kang. 2016. "Birthdays, Schooling, and Crime: Regression-Discontinuity Analysis of School Performance, Delinquency, Dropout, and Crime Initiation." American Economic Journal: Applied Economics, 8(1): 33-57.

February 2010Modeling College Major Choices using Elicited Measures of Expectations and Counterfactuals
with Peter Arcidiacono, V. Joseph Hotz: w15729
The choice of a college major plays a critical role in determining the future earnings of college graduates. Students make their college major decisions in part due to the future earnings streams associated with the different majors. We survey students about what their expected earnings would be both in the major they have chosen and in counterfactual majors. We also elicit students' subjective assessments of their abilities in chosen and counterfactual majors. We estimate a model of college major choice that incorporates these subjective expectations and assessments. We show that both expected earnings and students' abilities in the different majors are important determinants of student's choice of a college major. We also show that students' forecast errors with respect to expected earni...

Published: Arcidiacono, Peter & Hotz, V. Joseph & Kang, Songman, 2012. "Modeling college major choices using elicited measures of expectations and counterfactuals," Journal of Econometrics, Elsevier, vol. 166(1), pages 3-16. citation courtesy of

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