Association for Public Policy Analysis & Management

Can Teaching Assistants (TAs) in introductory chemistry labs reduce the disparity of minority representation in science? Using administrative data, detailed gradebooks, and observations from lab sections at a large public university, I examine the extent the ethnicity of TAs contribute to the academic performance and course persistence of students. The timing of TA assignments, impacted sections, and a no section switching policy foster a quasi-experimental setting. I leverage this to estimate the effect of students being assigned to a TA of their own race/ethnicity relative to another. Although I do not detect effects on lab grades or effort, I estimate a statistically significant 3.76 percentage point increase in the course completion rate. This occurs in a setting where the mean course completion rate is 91.6 percent.

Why might course completion rates in introductory chemistry labs matter? Large ethic and racial disparities exist in the fields of science and engineering. While Under-Represented Minorities (URMs) comprise of 26 percent of the US residential population over the age of 21, they account for only 10 percent of those employed in science and engineering (National Science Board 2015). Many link the inequality in representation for science occupations to low college degree obtainment by URMs. Consistent with occupational disparities, URMs only account for 13 percent of science and engineering degree holders with a bachelor’s degree or higher (National Science Board 2015).

Although initiatives that increase recruitment of minority undergraduates to four-year institutions may partly address disparities in science, they are unlikely to be a comprehensive solution. Among students who start at Four-Year public institutions, Asian and white students complete a degree within six-years at rates of 71.7 percent and 67.2 percent, while Hispanic and black students complete a degree at rates of 55 percent and 45.9 percent (National Student Clearinghouse 2017). The cause of the disparity is complex and includes factors that are beyond the control of a college.

This study focuses on a factor universities can control; the selection and recruitment of TAs. Over 130,000 individuals are employed as graduate TAs in the US (Bureau of Labor Statistics 2016). Unlike most other employees at a university, the selection of TAs occur frequently. Consequently, understanding the effects of TAs may be especially important for a university that is experiencing rapid demographic changes in their undergraduate population.