Economists sometimes use online job postings to gauge employment demand. But that data turns out to be an unreliable proxy. Why? For one thing, tech and other white-collar workers are more likely than others to search for jobs online—after all, that’s where many of them work—and so employers are more likely to post listings for those positions, often advertising the same job multiple times. Also, companies tend to flood job boards when the listing firms are offering discounts, regardless of their need for workers. Chris Aberle of Economic Modeling Specialists Intl., a company that tracks these numbers, says that although disparities may even out at a nationwide level, using postings to understand demand within a specific job category or region doesn’t really work. “This data is popular because it’s easier to understand than traditional labor market data,” he says. “But the risk of misapplication is very real.”
