I think the better question is what segments of the Chinese population were tested. I wouldn't be surprised if they over-represented high-performing students and under-represented other areas, either because of lack of resources or because of an intentional effort to boost the nation's scores.
The numbers do not make it to international journals if the sample would not be representative. School education in Eastern Asia is not less well equipped than in most European countries and US (the latter country really lacks ressources for that).
Many young Chinese people come to the US and become successful scientists.
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It is the quality of the education system that is responsible for a high average IQ.
So you think IQ is learned and not raw learning ability ? now I see why we have been having communication problems...
I saw the sign, and it opened up my eyes, I saw the sign.
Life is demanding, without understanding.
Dearest creature in creation
Studying English pronunciation,
I will teach you in my verse
Sounds like corpse, corps, horse and worse.
I will keep you, Susy, busy,
Make your head with heat grow dizzy;
Tear in eye, your dress you'll tear;
Queer, fair seer, hear my prayer.
Pray, console your loving poet,
Make my coat look new, dear, sew it!
Just compare heart, hear and heard,
Dies and diet, lord and word.