Foreign-Born Teaching Assistants Impair Undergraduate Performance
"American students enrolled in classes taught by foreign-born teaching assistants with limited English do tend to receive lower grades than those in classes taught by natives."
Ever since American universities began letting foreign-born graduate students teach undergraduate classes, those undergraduates have complained that their teachers' lack of English proficiency has compromised their education. In Foreign-Born Teaching Assistants and the Academic Performance of Undergraduates (NBER Working Paper No. 7635) , NBER Research Associate George Borjas concludes that American students enrolled in classes taught by foreign-born teaching assistants with limited English do tend to receive lower grades than those in classes taught by natives. His results suggest that at least one popular complaint, that foreign-born Teaching Assistants (TAs) lower the quality of American undergraduate education, may have some basis in fact.
Borjas surveyed 309 students enrolled in the third course of a three-course economics sequence at a large public university. Students typically did not know in advance which section would be taught by a foreign-born TA, and uniform grading across the course eliminated the possibility that differences in performance could be attributed to different TA grading scales. Students were asked about their experience in the first two courses in the sequence, the nativity of their TA, their final grade in each class, and their overall GPA. Other questions gathered information used to control for variations in ability and effort, both by the student and by the TA.
Although nearly 80 percent of the undergraduates said that foreign-born TAs had worse communications skills, the students considered the natives and the foreign-born equally well prepared for class. All else equal, the results suggest that switching a particular student from a section taught by a native-born TA to one taught by a foreign-born TA would reduce his grade in the course by 0.2 grade points. There was some evidence that better TA preparation could close the gap--estimates of final grades did not worsen if the switch was to a class in which the foreign-born TA was judged better prepared than his native counterpart.
The fact that about a quarter of the undergraduates surveyed were born outside of the United States allowed the effect of foreign-born TAs on foreign-born students to be compared with their effect on U.S.-born students. According to Borjas, "the evidence suggests that foreign-born graduate students do not have an adverse impact on the academic achievement of undergraduate students who are 'like them'--perhaps both in terms of language and culture--but do have an adverse impact on undergraduates who are sufficiently different."
-- Linda Gorman