Thursday, 27 February 2014

A few points of feedback

Can I just check a few issues about the blog?

Does the “Follow by email” function work? I assumed it would be helpful, but as far as I can see from the summary statistics, only 22 people are registered. If you have tried to register and encountered a problem, I will try to fix it.

Does the search function work? It had a phase a month or two back when there seemed to be a problem, but it seems have fixed itself.

Last, can you find the topics you are looking for? I don’t particularly want to move to another platform, but if topic search is difficult, I might have to consider it.

And, of course, any other feedback you might like to give, particularly about topics which need comment.

14 comments:

  1. Well ... I read a random commenter somewhere say that blacks can do fine on a 70 IQ where a white person would be disabled. a) Is that junk? b) any theories if not? It would be fascinating if true, possibly revealing weakness in the idea of IQ at the edges, or, revealing /something/ anyway.

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    1. Jensen covered this in the g factor, and Endre (below) has given you a link to the recent discussion led by Greg Cochran. I will do a small post sometime to cover the basic issues, but it does not invalidate intelligence testing. Rather, it shows an interesting finding about there being two paths to retardation: "natural" low intelligence and brain injuries and misfunctions of some sort

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    2. Let's say you have two populations, one with an average IQ of 97, such as Norwegians, for example, and another with an average IQ of 115 such as Brahmin immigrants to the US. Both of these populations would have members that are retarded (IQ of 70 or below) because of normal variation along the bell curve. These would be much rarer for the Brahmins than for Norwegians (less than one in five hundred for Brahmins, but approximately one in twenty-five for Norwegians). The extreme difference in these numbers are due to the bell shape of the gauss curve, see http://en.wikipedia.org/wiki/Normal_distribution

      In addition to these normal retarded people, there are those that are retarded due to an incredibly deleterious mutation, chromosomal abnormality and so on. These often look and act markedly differently from regular retards (think Downs.) If we assume this kind of retardation to be equal in the two populations, let's say 1% (I made up that number), we see that for Norwegians the normal retarded are 80% of the total, while for Brahmins the number is something like 15%. Therefore, it would seem on that for Norwegians an IQ of 70 means something different than for Brahmins (the former group would seem normal, the latter markedly different) but in terms of cognitive power they are probably pretty similar.

      Ps. I've had a few drinks so the back of the envelope calculations might be off, but I hope the post was understandable.

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  2. ... the "follow by email" function works for me. I receive your updates as you post them. Best, Johannes

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  3. It is not binary, but a matter of probabilities.

    It is easy to explain and not a defect of the tests. See: http://westhunt.wordpress.com/2013/07/02/mental-retardation/

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  4. i like checking your site on a frequent random basis, rather than being contacted automatically - my DNA prefers being pleasantly surprised rather than being told :)

    btw, the price is now down to $1500 US to have one's whole genome sequenced https://www.scienceexchange.com/facilities/kinghorn-centre-for-clinical-genomics

    & for irate 23&me folks who aren't allowed health info (b/c of our gov't FDA) one can download their 23&me results & snpedia.com will tell you how to upload them & get that health info for $5:)

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  5. These open threads are a good idea.

    As for papers that needs dissecting, this one has been making the rounds among the scientific illiterati lately: http://www.sciencemag.org/content/341/6149/976.abstract

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    1. You'll see Wicherts taking the authors to school here: http://www.sciencemag.org/content/342/6163/1169.4.full but I haven't seen a popular critique anywhere.

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  6. Jelte certainly takes the paper apart, in his inimitable style. Inter alia, he shows that when a test is too easy, and most people get either full marks or close to full marks, then you cannot easily use the data. I saw the paper last year, and simply passed over it because it was an experimental manipulation on smallish groups, and I can no longer be bothered with those.

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  7. This is a little late, but in my case email updates work just fine.

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  8. Idea for post (defense of behavioral genetics):

    In the latest answers to the edge question (http://www.edge.org/responses/what-scientific-idea-is-ready-for-retirement) Sapolsky argues that the nature-nurture concept is ready for retirement. His reasoning is that there is never such a thing as a gene acting without an environment (variations of this tautological argument are very common). As far as I can see, if some trait seems to be affected by the same genes in the same way across all environments possible to measure (we can do no better), then there is no gene-environment effect for these genes except in the trivial sense no-one denies. Or is my reasoning too simple?

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    1. See Hsu on beanbag genetics: http://infoproc.blogspot.no/2013/10/beanbag-genetics-blood-pressure.html

      And what happened to average evoked potentials? Was there anything there? See here: http://books.google.no/books?id=Au2KHXQs2JUC&pg=PA223&lpg=PA223&dq=average+evoked+potential+iq&source=bl&ots=f8_znJdqrz&sig=Ji7qv1e9huwDsNwfvSuV1LkIpb8&hl=no&sa=X&ei=5gAXU4DqGcXnygP924KoDg&ved=0CDEQ6AEwAA#v=onepage&q=average%20evoked%20potential%20iq&f=false for an explanation of the concept.

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    2. If genes have consistent effects across most environments that is important to know. Advantage genes. If environments have consistent effects across genes, also important to know. Advantage environments. I still find the concept useful. I also find heritability coefficients useful. AJ Figueredo will be talking about this next month.

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    3. By the way, the Sapolsky argument is that genes never cause a particular effect on their own, and that all gene effects are examples of gene-environment interaction. They are ubiquitous and not exceptional. I think this is stretching things somewhat. If that were so we would find low heritability for intelligence, given the different environments in which humans live. So, I disagree with his argument. In fact, looking through the Edge contributions, I find I also disagree with Nina Jablonski that race does not exist.

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