No test measures intelligence. A test only measures you relative to the persons that wrote the test. – loosely quoting Asimov.
2007 is ancient history now. It is an interesting graph that one might correlate with a lack of meritocratic structure in society, but I’m on the low end cause I say this without looking up and reading the study. Pretty pictures evoke emotional blabbering bias and all that.
Very interesting. I imagine an even simpler explanation for why poorer kids do less well in school:
You simply can’t focus on abstract thoughts if you’re lacking basic ingredients in your life.
It’s something like the pyramid of needs:
When you’re hungry in school because you didn’t have proper breakfast because your parents had too little time to prepare one or were unable to actually buy proper-quality ingredients, your brain simply can’t focus on geography of the other end of the world or god forbid, calculus.
I guess that if schoolkids were given free meals before school and during midday break, their performance in school-related activity would improve by at least 50% in poorer regions.