Autism link to air pollution raised
bbc.com
bbc.com
I doubt you'd be comparing apples to oranges over a long timeline. Actually, I don't think it's a slam dunk that we have more autism today, or more diagnoses.
It is interesting that these sorts of articles ("BPA exposure associated with 7 point IQ decrease" was a recent one on the HN front page) seem to gloss over the fact that when these exposures were higher, the Flynn Effect continued unabated. Lead is another substance that, although nasty, is blamed for IQ declines, yet, when lead levels were highest, average IQs continued to rise. Now that lead levels are plumbing new lows, is there evidence that those "lost" IQ points have been gained by younger generations? If BPA is banned, I am sure that there will be scant evidence of those 7 IQ points coming back in a generation or 2 (if anyone bothers looking). Your point about inter-generational autism rates is similar.
I'm not an expert, but I can't take these sorts of environmental toxicity studies seriously anymore.
In other words, even if rate of incidence is declining, rate of diagnoses has sharply risen in recent decades, complicating the data.
That's not correct, this research says nothing about other factors that could affect the rate of occurrence of autism.
I think it's safe to say, that, in the West, air pollution has dropped dramatically: https://en.wikipedia.org/wiki/Great_Smog
There are probably more APIs out there. Autism numbers by location should be known. Simple correlation could go a long way to check the consistency of the hypothesis.
EDIT: The autism data needed would be age of diagnosis, to map it to the proper air quality metric.
It seems that autism has the same pattern. It has genetic aspect and environmental aspect and one of personal experience and amount of practice, so no one could identify all the factors, leave alone find a "single cause". Of course, it is genes, for, say 80% (which is rather a flawed mental construct), like it is in everything else - height or IQ, for example (why should it be different?), but the rest 20% are, of course, not mere "air pollution".
It is the same meme-nonsense (with which we're bombarded daily by mainstream media) as to say, "look, children in a toxic environments have worse grades and misbehave more". OK, perhaps they are, but this is an "empty message", a "meme" based on a naive common-sense. Correlation does not imply causation, and even if this factor is a "valid" one, its actual implication is infinitesimally small - it, perhaps, contributes to "stress" or states related to "depression" (which is another meme). Most of these meme-studies are just misuse of statistical tools together with a confirmation and self-serving biases. People construct statistical "evidences" for their own flawed constructs, instead of methodically removing everything "mental" and see what remains.
We should choose the more charitable interpretation, not because there aren't idiots out there, but because doing so leads to more interesting discussion in the long run—and usually in the short run too.
The first question is "How does they manage to properly test this "link" with a distinct control group". Could you explain, please.
So, I prefer to read Simon Baron-Cohen.
If you have specific information about this or relevant research, by all means contribute it. But railing against idiocy in a generic way lowers the signal/noise ratio of the threads: if generic it must be predictable, and if predictable it can add no information. The Principle of Charity is so good for counteracting this that we may add it to the HN guidelines.
Intellectual charity doesn't require accepting anything false. It means that when there are several reasonable interpretations, you should pick the strongest. This goes against the default tendency we all have, to pick the weakest to then have the pleasure of overturning it. That pleasure is strong—so strong that one may begin seeing idiots for it—and it overpowers the pleasures of curiosity, which is what we're going for.