A group of researchers have found that minority students in community colleges tend to perform better when they’re taught by minority instructors — particularly those of similar race or ethnicity, writes Suzy Khimm at the Washington Post.

A new National Bureau of Economic Research paper explains how the minority performance gap narrows.

According to research at California’s De Anza College, one of the biggest community colleges in the United States, black, Hispanic, Asian and Native American students are 2.9 percent more likely to pass courses with instructors of a similar racial or ethnic background.

The paper’s authors — Robert Fairlie, Florian Hoffmann and Philip Oreopoulos explain:

“We find that the performance gap in terms of class dropout and pass rates between white and minority students falls by roughly half when taught by a minority instructor. In models that allow for a full set of ethnic and racial interactions between students and instructors, we find African-American students perform particularly better when taught by African-American instructors. . . . The class dropout rate relative to Whites is 6 percentage points lower for Black students when taught by a Black instructor. Conditional on completing the course, the relative fraction attaining a B-average or greater is 13 percentage points higher.”

They conclude that this effect is due to the students’ positive reactions to minority teachers — what other researchers have dubbed the “role-model effect”:

“First, we find dropout effects from instructor race and ethnicity prior to receiving grades. This outcome is entirely determined by the student rather than the instructor. Second, as shown in table 4, it is the young students who are most affected by the instructor’s minority status . . . young students are likely to be susceptible to role-model effects, while older students are not.”

The researchers also point out that only 9.6 percent of all full-time faculty members at U.S. colleges are black, Latino or Native American, while those groups compose one-third of the entire college-age population.