Title: Essays on Effects of Educational Inputs
Description: This dissertation contributes to the ongoing debate on how educational inputs make a difference and how to allocate them efficiently. Educational inputs could be broadly defined as any personnel inputs such as teachers and career service staff, learning environment that includes peers and school facilities, and policies that facilitate learning. This dissertation explores three topics: peer effects in higher education, the consequences of college expansion, and the impacts of school closures. Chapter I estimates the peer effects of non-cognitive skills. I show how peers’ non-cognitive skills influence students' academic outcomes and own non-cognitive skills. I use a unique dataset that includes information on student non-cognitive skills, course grades, and friendship from a university in China that randomly assigns students to dormitories. My first main finding is that peers’ non-cognitive skills affect students’ academic outcomes positively but differentially. All students benefit from exposure to “persistent” peers, while students with low baseline academic ability also benefit from exposure to “motivated” peers.

My second main finding is that peers also affect the development of students’ self-control and willingness to socialize. These findings have important implications in evaluating the social returns to interventions that improve non-cognitive skills and education policies that change peer group composition. Chapter II summarizes the current literature on college expansions, which change the education resource for many students. Studies have explored the impact of College Expansions that happened worldwide and this chapter summarizes literature in the field of economics of education. This chapter pays special attention to studies that explore the impact on wages and employment and how current studies identify causal relationships. Meanwhile, this chapter reviews how current studies examine the impacts of college expansion in China starting from 1999, which was unparalleled in magnitude. Finally, I discuss how future studies could improve to identify causal effects of the impact of the tremendous college expansion in China.

Chapter III, a joint work with Ying Xu, estimates the effect of school closures causedby wildfires. School closures are a common and disruptive feature of education systems when sudden shocks from weather, natural disasters, or infectious disease require that students remain at home rather than in the classroom. Indeed, since January 2020, school closures have happened all around the world due to the COVID-19 pandemic. In the United States, more than 50 million students are currently out of school due to COVID-related closures. This raises an important question: How do sudden school closures affect student development in the short and medium term? In this chapter, we use administrative data to examine the causal effect of unexpected school closures, exploiting sudden variations in these closures due to wildfires in California. We show that unexpected closures have negative effects on student test scores, and the loss of school time is one of the most important mechanisms of decline in student achievement.

Meanwhile, minority students and students from school districts with low socioeconomic status experience larger negative effects from such unexpected closures. We argue that these results can help inform policy to identify and address the negative impacts of such closures.