/cdn.vox-cdn.com/uploads/chorus_image/image/35223320/450621536.0.jpg)
President Obama, among others, likes to say that the US has the "world's best universities." That claim, though, refers the tip-top of prestigious universities: The US has 11 of the top 15, according to one international ranking.
So how good are US colleges overall, really? Kevin Carey, the director of the New America Foundation's education policy program, recently argued in the New York Times that they aren't that great, given that American adults — even college graduates — don't perform well on an international test of adult skills. And Education Secretary Arne Duncan said Wednesday night that he generally agrees.
But this isn't entirely fair to America's colleges. The problem, really, is America's college students.
It's true that "the world's best universities" mostly refers to the quality of American research, not teaching. (In fact, studies have found little, if any, relationship between research productivity and the quality of undergraduate education.) It's also true that on the OECD's test of math and literacy skills, American adults don't fare well, particularly in math.
But there's a simple explanation for this, which makes it hard to tell how good American colleges actually are: American students are starting college farther behind than students in better-educated countries.
American students get about average scores on the Programme for International Student Assessment, the international test used to measure the skills of 15-year-olds globally. And while policymakers are concerned that the US is falling behind in college attainment rates, an above-average portion of Americans still end up earning a college degree.
So America has average students heading to college in above-average numbers. The result, in studies, is that the mediocrity is magnified.
Meanwhile, Korean and Finnish students end high school ahead of American students, as measured by the OECD's tests, and also graduate from college in high numbers. So it's no surprise that their college graduates rank higher than our do. Asking American colleges to make up the difference isn't entirely fair.
A better assessment of how good American colleges are, relatively speaking, would have to look at where students stand relative to their international peers when they enroll, and then look again at graduation. It's possible students do learn a lot in college — just not enough to catch up with those from other countries who had a head start.
This is a well-understood, if controversial, concept in K-12 education. Teachers are increasingly judged based not just on students' standardized test scores, but on how students are performing relative to expectations. So a teacher with a classroom full of fifth-graders who do math at a third-grade level might be rewarded, not punished, if those students had started the year at a first-grade level. They haven't caught up yet, but teaching two full years of math in one academic year is a pretty amazing achievement.
But an international value-added comparison for higher education is a long way off. Some American colleges already measure learning gains, but the results are neither public nor national. (Some prominent studies and books have argued that these scores show many undergraduates don't learn much.)
Meanwhile, higher education in other countries is so different that in some cases making a comparison valid would be incredibly difficult, if not impossible. The best universities in France, for example, often require two years of very intense preparatory school between high school and college. It's hard to figure out how to compare US colleges to that.