WINNING THE WAR ON WAGES:

Between 2006 and 2013 -- the latest round of IPEDS data available -- fully online bachelor's degrees got a price cut, the researchers write. Weighted for enrollment, the median cost (in 2014 dollars) of a full-time online undergraduate degree dropped by 34 percent, while an equivalent face-to-face education at a nonselective public institution rose 9.2 percent. Tuition for traditional programs at large for-profit and nonprofit institutions, meanwhile, posted a more modest decline of about 8 percent.

The researchers also found "modest evidence" that colleges and universities that grew their fully online student populations cut the cost of tuition. Between 2006 and 2013, they found, a 10 percent growth in an institution's online student population lowered the cost of tuition for all students by 1.5 percent. That finding only applied to the for-profit and public sectors of higher education, however -- the researchers found "no detectable impact" at private colleges and universities.

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