Publication Date


Document Type


First Advisor

Wilcox, Virginia

Degree Name

Ph.D. (Doctor of Philosophy)

Legacy Department

Department of Economics


This dissertation contains three essays on the impact of immigration, especially high-skilled immigration in the United States. The first essay addresses the question of whether the effect of the Great Recession on unemployment of immigrants in the United States has been different from the impact on the unemployment of natives. Significant differences are identified when immigrants and natives with different levels of education are treated as separate groups. For a native-born citizen, a higher level of education is associated with shorter unemployment duration. But for an immigrant, the higher the level of education he or she obtains, the longer his or her duration of unemployment.

The second essay seeks to answer the question of whether the presence of foreign high-skilled workers boosts or hurts native worker employment. By differentiating the composition of H-1B visa holders and studying the effects of visa lotteries in 2007 and 2008, I find that "low quality" foreign workers hurt native employment while "good quality" foreign workers benefit native employment.

The third essay assesses the impact of the Optional Practical Training extension ruling on international students' retention decisions. I adopt a difference in difference in difference approach and find an overall significantly positive effect of the new ruling on STEM students' usage of OPT after graduation.


110 pages




Northern Illinois University

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