The U-Shaped Curve study you linked does not seem to support really any solid conclusion about a T-vs-IQ relationship (in this quote, S men = “successful educational level”, NS men = “unsuccessful educational level”):
In the total sample (S + NS men), the correlation between T to IQ was best described by a polynomial regression (3rd order), exhibiting an inverse U-shaped regression.
In S-men, the relationship between T and IQ was best described by a polynomial regression equation of the 3rd order; however, the relationship was not U-shaped, but rather a positive correlation (low T: low IQ and high T high IQ).
In NS-men, there was an inverse U-shaped correlation between T and IQ (low and very high T: low IQ and moderate T: high IQ)
So there are three totally different best regressions depending on which population you choose? Sounds fishy / likely to be noise to me.
And in the population that most represents readers of this blog (S men), the correlation was that more T = more IQ.
I’m only reading the abstract here and can’t see the actual plots or how many people were in each group. But idk, this doesn’t seem very strong.
The other study you linked does say:
Interestingly, intellectual ability measured as IQ was negatively associated with salivary testosterone in both sexes. Similar results were found in our follow-up study showing significantly lower testosterone in gifted boys than controls (Ostatnikova et al. 2007).
which seems to support the idea. But it still doesn’t really prove the causality—lots of things presumably influence intelligence, and I wouldn’t be surprised if some of them influence T as well.
I only linked the U-shaped study to mention that someone had said something vaguely similar. Notice my words “people have posited a U-shaped curve...”. Study indeed seems like garbage. Perhaps i should’ve said that explicitly.
But it still doesn’t really prove the causality—lots of things presumably influence intelligence, and I wouldn’t be surprised if some of them influence T as well.
Yes so the experiment is that a million people are starting up in taking hormones/blockers now. I don’t think proper results are in but what I have myself observed seems like strong evidence that blocking T preserves or raises intelligence on the margin.
The U-Shaped Curve study you linked does not seem to support really any solid conclusion about a T-vs-IQ relationship (in this quote, S men = “successful educational level”, NS men = “unsuccessful educational level”):
So there are three totally different best regressions depending on which population you choose? Sounds fishy / likely to be noise to me.
And in the population that most represents readers of this blog (S men), the correlation was that more T = more IQ.
I’m only reading the abstract here and can’t see the actual plots or how many people were in each group. But idk, this doesn’t seem very strong.
The other study you linked does say:
which seems to support the idea. But it still doesn’t really prove the causality—lots of things presumably influence intelligence, and I wouldn’t be surprised if some of them influence T as well.
I only linked the U-shaped study to mention that someone had said something vaguely similar. Notice my words “people have posited a U-shaped curve...”. Study indeed seems like garbage. Perhaps i should’ve said that explicitly.
Yes so the experiment is that a million people are starting up in taking hormones/blockers now. I don’t think proper results are in but what I have myself observed seems like strong evidence that blocking T preserves or raises intelligence on the margin.