3 ms·

But the numbers you describe are for adult height, right? Wouldn't you expect a much stronger effect if your sample was a mix of (say) 4-6th-grade kids. I think

• Beldin 7y ago
  Kids do not grow in lock-step. I.e., kids who will have exactly the same height as adults will have (probably considerably) different heights at the same age while growing up. Given that, i doubt height measured at any one (age)point during childhood strongly correlates with iq. You'd need sufficient data to be able to reliably predict height as an adult for that, would be my guess.
• xyzzyz 7y ago
  No, this is also found in children. See e.g. this[1] study, which also by design (it's a twin study) rules out the hypothesis that the effect is mostly environmental. [1] - https://www.ncbi.nlm.nih.gov/pubmed/17081263 https://www.ncbi.nlm.nih.gov/pubmed/17081263
  • iguy 7y ago
    Thanks. That there is signal in which twin is taller at precisely age 12 is interesting, and seems like the same phenomenon as the adult effects. But I'm saying something much simpler. In a school class, there's another effect, that the oldest may be a year or more older than the youngest. The mix of ages in a classroom will produce a correlation all by itself. It seems to me this would be a much bigger effect: 7th-graders are quite a bit taller, and better on tests, than 6th-graders.
    • xyzzyz 7y ago
      Ah, that's a good point. It would probably require looking deeper into the studies to see how it is controlled for, if at all.