A new study from three Princeton University economists paints a bleak portrait of the long-term unemployed — those who have been out of work for at least six months.

Only 11 percent of those 3.8 million people find a job within a year, according to the report by Alan Krueger, a former top economist for President Barack Obama; Judd Cramer; and David Cho.

Long-term unemployment hampers job searchers in two ways, the economists say, according to CNBC.com. First, these people become discouraged and stop looking as hard for a new position as those who lost their jobs more recently.

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And second, when they apply for job openings, the long-term unemployed are often looked at unfavorably by employers, the economists say, CNBC.com reports. The employers are concerned that these people's skills aren't up to date and that their long hiatus from work shows they're less competent.

All this puts the long-term unemployed "on the margins of the labor force," the study says, according to CNBC.com.

Many of them have dropped out of the workforce. "A concerted effort will be needed to raise the employment prospects of the long-term unemployed," the economists write.

But some other economists were encouraged by the 175,000 gain in February payrolls. "It reinforces the case for the economy being stronger than it's looked for the last couple of months," Bill Cheney, chief economist at John Hancock Financial Services, told Reuters.

"It makes life easier for the Fed and feeds into continuing the tapering process."

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