College for the Masses

David Leonhardt:

The fate of students like Mr. Escanilla is crucial to today’s debate over who should go to college: How much money should taxpayers spend subsidizing higher education? How willing should students be to take on college debt? How hard should Washington and state governments push colleges to lift their graduation rates? All of these questions depend on whether a large number of at-risk students are really capable of completing a four-year degree.

As it happens, two separate — and ambitious — recent academic studies have looked at precisely this issue. The economists and education researchers tracked thousands of people over the last two decades in Florida, Georgia and elsewhere who had fallen on either side of hard admissions cutoffs. Less selective colleges often set such benchmarks: Students who score 840 on the SAT, for example, or maintain a C+ average in high school are admitted. Those who don’t clear the bar are generally rejected, and many don’t attend any four-year college.

Such stark cutoffs provide researchers with a kind of natural experiment. Students who score an 830 on the SAT are nearly identical to those who score an 840. Yet if one group goes to college and the other doesn’t, researchers can make meaningful estimates of the true effects of college.