Just as important, however, from the perspective of an employer, those who read good things about a company also typically demanded smaller pay increases in order to change jobs.

Those who read negative reviews demanded an average increase of between 55 percent and 60 percent. Those who saw a neutral review wanted a 45 to 50 percent pay raise. Those who read positive reviews said they would like a 35 to 40 percent salary bump.

The researchers say there are two distinct reasons online reviews shape a person's willingness to apply to work for a company.

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One is that reviews lead people to make judgments about whether the employer would provide a work environment and culture that they would enjoy. The second, however, has to do with whether people would be proud to work for the employer.

"What these results are telling us is that online employer reviews seem to influence not only participants' opinions of the company, but also their expectation of how other people would view it," the authors write. "The latter is especially important because people care about others' opinions of organizations they are affiliated with, including their employer."

If employers — particularly those that aren't well-known — hope to attract qualified employees at salaries they can afford to pay, they would be wise to monitor online review sites, the study concludes. Responding directly to criticism on such websites is a good bet, says the report.

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Of course, the best long-term strategy to reduce negative reviews online is rather simple: Listen to the criticism and treat your employees better.