UCLA

Sociology and social stratification researchers have long been concerned with the issue of educational inequality, as education is considered a key tool for achieving social mobility and has been shown to be a powerful determinant of an individual's opportunities and quality of life in modern society (Blau and Duncan 1967; Hout 1988; Fischer and Hout 2006). Given the significant role that education plays in determining social mobility, there has emerged a dynamic of competition between social classes for attaining higher education. While marginalized classes seek to overcome their disadvantaged status through education, thus allowing them greater social mobility, higher classes continuously enact social closure behavior through education to secure their advantaged status. Therefore, education is one of the most competitive endeavors in modern society. In this dissertation, I explore the class dynamics of acquiring educational advantages given educational expansion in the United States and South Korea (hereafter Korea). Of key interest are strategies of securing social mobility through education that entail a move away from public education and increased reliance on resources outside of formal schooling. In this dissertation, I examine the effect of three extra-curricular activities on education and labor market outcomes, with a particular focus on the transitional periods of entry into and exit from postsecondary education, along with patterns of student retention and attrition during the years of college enrollment.

Specifically, the first chapter of my dissertation uses data from the Educational Longitudinal Survey of 2002 to look at the average and heterogeneous effects of shadow education on SAT scores. The data include extensive information on not only students' socioeconomic background, but also high school information such as GPA, educational aspirations and motivation, which is helpful in estimating the propensity to shadow education and the relationship between shadow education and SAT scores. I use PSM to examine the average relationship between shadow education and SAT achievement, paying attention to the issue of pretreatment heterogeneity. Also, using the stratification-multilevel and smoothing-differencing methods, I examine how the effects of shadow education vary according to likelihood of receiving shadow education. I find that shadow education has significant positive effects on SAT scores and that the effects vary by individual propensity to use shadow education. The pattern of treatment effect heterogeneity indicates positive selection, which indicates that those who are more likely to use shadow education--those who are socioeconomically advantaged--benefit more from shadow education than those who are less likely to use it. Also, public resources such as school prep courses, books, and videos, neither alleviate the effects of private shadow education nor change the pattern of the treatment effect heterogeneity. My findings suggest that shadow education is an emerging mechanism that exacerbates educational inequality in the United States.

In the second chapter, using the National Longitudinal Survey of Youth from 1997, I examine the relationship between college student employment and dropouts. Since NLSY97 is surveyed annually and includes extensive information about students' educational backgrounds such as high school academic achievements, college financial aid, and the respondent's educational history, it is particularly useful to examine how student employment affects first year attrition and bachelor's degree completion. Using PSM, I estimate the average effects of treatment on the treated and I verify evidence of the treatment effect heterogeneity of student employment on college dropout by using the stratification-multilevel and smoothing-differencing methods. In this chapter, utilizing complex counterfactuals, (e.g., intense work [20 hours or more] vs. moderate work [less than 20 hours] vs. no work), I also examine variations in the effect of work intensity on dropout. In this study, I find that engaging in intense work has deleterious effects on first-year retention and on graduation within six years; however, the effects of intense work vary by likelihood of participation in intense work. The most advantaged students--who are least likely to engage in intense work--experience the most negative consequences from intense work, while such activity is less harmful to those from disadvantaged social backgrounds. I also find that this effect heterogeneity can be attributed to different financial situations and reasons for working between advantaged and disadvantaged students. This finding has two key implications. First, advantaged students should carefully consider engaging in intense work, as it can negatively affect bachelor's degree completion. Second, although the effect of intense work is less harmful for disadvantaged students, providing sufficient financial aid to them is still an important task, as this could help them to balance the intensity of work and school life.

The final chapter of my dissertation aims to examine the effects of English training abroad (hereafter ETA) on labor market outcomes in Korea. To examine how ETA affects employment and wages, I conduct survival analysis and quantile regression using data from the Korea Employment Information Service's 2007 Graduate Occupational Mobility Survey. The key finding of this study is that even though the average effects of ETA seem to be modest as most prior research has indicated, ETA does appear to have substantial positive effects on getting a good job and earning higher wages. ETA proved especially helpful for those who did not attend elite colleges. That is, ETA is a useful tool for non-elite students to supplement their weak formal education. Based on these findings, I conclude that ETA has a substantial impact on labor market outcomes in South Korea, and thus labor market opportunities are strongly determined by an socioeconomic background, as the cost of participation in ETA presents a barrier to entry for individuals from lower socioeconomic backgrounds.