To avoid such complications, the Yale researchers sought to design the simplest study possible. They contacted professors in the biology, chemistry and physics departments at six major research universities — three private and three public, unnamed in the study — and asked them to evaluate, as part of a study, an application from a recent graduate seeking a position as a laboratory manager.

All of the professors received the same one-page summary, which portrayed the applicant as promising but not stellar. But in half of the descriptions, the mythical applicant was named John and in half the applicant was named Jennifer.

About 30 percent of the professors, 127 in all, responded. (They were asked not to discuss the study with colleagues, limiting the chance that they would compare notes and realize its purpose.)

On a scale of 1 to 7, with 7 being highest, professors gave John an average score of 4 for competence and Jennifer 3.3. John was also seen more favorably as someone they might hire for their laboratories or would be willing to mentor.

The average starting salary offered to Jennifer was $26,508. To John it was $30,328.

The bias had no relation to the professors’ age, sex, teaching field or tenure status. “There’s not even a hint of a difference there,” said Corinne Moss-Racusin, a postdoctoral social psychology researcher who was the lead author of the paper.

Dr. Handelsman said previous studies had shown similar subconscious bias in other occupations. But when she discussed the concerns with other scientists, many responded that scientists would rise above it because they were trained to analyze objective data rationally.

“I began to, on the one hand, wonder, ‘Well, perhaps that’s true: maybe people who are trained to be objective have some way of ferreting these out,’ ” she said. “But on the other hand, if scientists were no different from all the other groups that have been studied, that’s something that we should know.”