That is bound to fail because it would be a wild goose chase, there are a thousand variables, and the temptation is strong to try to isolate the ones that lies close to one's own ideological prejudices and ignore the rest, Note for example the focus on equality here and not on the fact that Finland's schools are more disciplinarian than schools in the rest of Western Europe. If you dig up the statistics you can see how little Finland's pupils are enjoying school, more akin to Japan than the rest of Western Europe, but the results are better than the rest of Europe (which certainly doesn't lag Finland in equality).