A centralized committee began conducting an initial review of applicant résumés, and the Fed started prioritizing qualities key to success in the job, like collaboration and teamwork. It took into account work experience and activities beyond the classroom. And the board standardized interview questions, so that instead of chatting about shared experiences, candidates and interviewers would focus on job-related skills.

Grades were kicked to the curb as a be-all and end-all, Ms. Bayer said.

“If a student comes in with a 3.9 G.P.A. from college, it means they hit the ground running in college,” she said. “That’s another tendency for economists: Just set a higher quantitative bar. You’re going to omit a lot of fabulous people that way.”

The new approach has had an impact. The Fed Board employed 150 research assistants in 2017, 39 percent of them women. That is up five percentage points from four years earlier. Minorities made up 29 percent of economists, up six points, Brookings found.

The Fed’s push illustrates how gender, racial and ethnic imbalances, often assumed to be unavoidable given the available crop of qualified students, might be possible to change with reworked selection criteria.

In fact, the hiring revamp created a sort of natural experiment.

The central bank mainly hires in two rounds, fall and spring, and the autumn phase began updating its hiring approach seven years ago. It has mostly driven the Fed’s recent gains in gender parity. The spring round, which has been slower to adopt the new procedures, has also lagged in gender balance.