When the job market was flooded with desperate applicants, manyemployers required college degrees for entry-level jobs. Therewas a certain cruel logic to it: Hey, might as well get thebest.

Related: Top college grads aren't always top workplaceperformers

The job market is much tighter now, but it appears thatemployers haven't relaxed their hiring criteria. That could explainwhy 43 percent say finding enough candidates is a topchallenge in filling entry-level jobs. It's a classic exampleof shooting yourself in the foot, but of course it's also bad forthe young people without college degrees who can't get onto thebottom rung of the career ladder.

Psychology, and office politics, may be at work here.No human resources person wants to be seen lowering hiringstandards. "The past couple of decades there was a prettysignificant trend toward up-credentialing," says Abigail Carlton, amanaging director at the Rockefeller Foundation.

"There’s a certain amount of path dependency once you start toput new requirements in. It would be harder to take them out thanto put them in."The foundation released a survey today that shedslight on the damage that can be done by insisting on collegediplomas for jobs that don't really require them.

Related: Undergrads expect high salaries, 401(k)matching

It interviewed a thousand young people, half recent collegegraduates and half "opportunity youth" — unemployed high schoolgraduates. It also interviewed some HR types and C-suiteexecutives.

Half of the recent college grads (49 percent, to be precise)said they didn't have to go to college to acquire the skillsthey needed for their current jobs, and 86 percent of themsaid they were learning things on the job that they didn't learn incollege. Three-quarters of the opportunity youth agreed that nothaving a college degree limited their options.

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"Screening for college degrees in the hiring process deniesopportunity youth the ability to get a foot in the door, buildskills on the job, and create more meaningful opportunities forlife-long career success," the report said. Instead, they fallfarther and farther behind.

Their predicament is illustrated by a striking number inthe report: 75 percent of the employers surveyed said the diplomais an effective way to narrow the pool of applicants and speed upthe hiring process.

More than 60 percent said a college degree is an effective wayto assess an applicant's work ethic, personal skills, and mentalcapacity. But if a diploma means you're bright and hard-working,there's a danger of assuming that without one you're not.

The Rockefeller Foundation is supporting research on two wayshiring departments could find good people without demanding acollege degree. In one approach, a Rockefeller granteenamed Incandescent is partnering with a company called Knackthat uses customized video games to assess applicants' skills.

In a pilot involving 600 opportunity youth, 83 percent performedat or above the level of a company's average performers for one ormore entry-level jobs. Using another approach, Innovate+Educate,which is based in Santa Fe, New Mexico, conducted a job fair lastspring in Albuquerque in which resumes were not only not required,but prohibited.

The idea was to rely strictly on skills assessment, leveling theplaying field for opportunity youth who lacked experience. Twentyemployers and about 600 applicants participated. A little over halfgot jobs, and about 260 still have them, Carlton says.

Meanwhile, a lot of employers continue to look for thatcollege degree and come up empty-handed. How smart isthat?

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