Clifford Adelman in Inside Higher Ed:
Indeed, they don’t, and one doesn’t need more than 4th grade math to see the problems with population ratios, particularly in the matter of the U.S., which is, by far, the most populous country among the 30 OECD member states.
None of our domestic reports using OECD data bothers to recognize the relative size of our country, or the relative diversity of races, ethnicities, nativities, religions, and native languages — and the cultures that come with these — that characterize our 310 million residents. Though it takes a lot to move a big ship with a motley crew, these reports all would blithely compare our educational landscape with that of Denmark, for example, a country of 5.4 million, where 91 percent of the inhabitants are of Danish descent, and 82 percent belong to the same church.
For an analogous common sense case, Japan and South Korea don’t worry about students from second language backgrounds in their educational systems. Yes, France, the UK, and Germany are both much larger and more culturally diverse than Denmark, but offer nowhere near the concentration of diversities found in the U.S. It’s not that we shouldn’t compare our records to theirs; it’s just that population ratios are not the way to do it.