By Amanda Pallais
A growing body of research shows that minorities face bias in the job-application process. But we know less about how bias plays out when minorities are hired, especially in regard to on-the-job performance and productivity.
Recent research I conducted along with Dylan Glover and William Pariente addresses this gap. We find that when managers hold negative beliefs, even unconscious ones, about minority workers, those workers perform worse than with unbiased bosses. Managers’ biases can become self-fulfilling prophecies.
Our study involved newly hired cashiers at 34 outlets of a French grocery-store chain. These cashiers were ideal to study because they worked with different managers on different days, so we could compare the same worker’s performance under different managers. They had no control over their schedules or which managers they worked with, so they couldn’t avoid supervisors they disliked. Moreover, workers’ schedules were determined quasi-randomly by a computer program, which ensured that all employees worked with the same managers under similar conditions.
We classified workers of North or sub-Saharan African origin as minorities, identifying these workers based on the origin of their names because it’s illegal in France to ask a worker about his ethnicity. We measured managers’ bias toward minorities with an Implicit Association Test, widely used in psychology to measure unconscious bias.
Minorities in these stores performed on par with other workers. However, when minority employees worked with unbiased managers, they served 9 percent more customers than other workers and ranked in the 79th percentile of worker performance.
Why does manager bias affect worker performance? Surprisingly, it wasn’t that biased managers explicitly treated minorities poorly. Minorities simply had less interaction with biased managers during their shifts. It seems that those managers didn’t pay as much attention to them. This is consistent with research that finds that individuals with biases toward a group are less likely to speak to members of that group. In our study, biased managers spent less time managing minority employees. The result was a drop in employee productivity.
Amanda Pallais is an associate professor of political economy and social studies at Harvard University and a faculty research fellow at the National Bureau of Economic Research.