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Medical IQ Question - Dealing with population mean.

  1. Oct 18, 2006 #1
    I was discussing Plato's Republic in class and we got into eugenics. Anyway, I remember hearing somewhere that IQ always deviates towards the population mean, and, therefore, it is not true that eugenics will result in benefits for the population (at least when done on the basis of IQ). Is this true, debated, been disproven? What source am I thinking of or?

    Thanks
     
  2. jcsd
  3. Oct 18, 2006 #2

    selfAdjoint

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    "Regression to the mean" happens with every type of normaly distributed quantity, not just IQ. If you pick two examples at random, and one of them is way up or down on a tail of the distribution, the other is likely to be closer to the mean. That's just common sense; the first one was a "lucky draw" of an unlikely event, and you wouldn't bet on that happening twice in a row.

    Now apply that to the heights of parents and children. Say a very tall father; he plays the part of the first unlikely observation. Then we expect his son to be shorter than ol' dad, or "regress on the mean". But note! If you first pick a very tall son, it's his father who is likely to be shorter!

    All this assumes there is no correlation between the numbers you pick, let alone a causal relations saying that tall fathers are biologically likely to have tall sons no matter what the probabilities are. So the regression argument really can't be applied to cases of clear biological causation.
     
  4. Oct 19, 2006 #3
    What about this?

    Genius A and Genius B have a child. Child C is probably less intelligent than Genius A and Genius B? Would this be true?

    If so, doesn't this refute the idea of IQ-based eugenics as a means of creating a smarter population? It doesn't mean eugenics cannot work, of course, just not when done based on intelligence (if IQ is correct).
     
  5. Oct 20, 2006 #4

    selfAdjoint

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    You have not absorbed what I wrote. First of all, there's nothing special about IQ in regression to the mean, it's a general result about staistically distributted data. Secondly consider the inverse case; Ma and Pa have a genius child. It's more probable than not that Ma and Pa are not geniuses. Joe has a genius brother; it's more probable than not that Joe is not a genius. You take two individuals at random from the distribution and if one is a genius (or a drooling idiot) it is likely the other isn't.

    What does this prove? Not a damn thing, because over 60% of the variance of the IQ distribution is accountable to inheritance, which means that at most the other 40% is statistically distributed. And maybe less!

    And if your argument that this disproves euggenics were true, breeding of animals would be impossible too. If you breed a championship sire and dam, most of their offspring are likely to be of lower quality. Sure, and then you cull. This is what makes eugenics nasty; to make it work you have to cull; you can't achieve major results with just positive breeding programs.
     
    Last edited: Oct 20, 2006
  6. Oct 20, 2006 #5
    Ah, I see. Sorry I didn't absorb it right away. I think I understand it now, and I definately see my argument is flawed, but it does (I think) reveal (as I think you mentioned) how it is neccessary to cull for eugenics to work.
     
  7. Oct 22, 2006 #6
    Wait, what's the difference? If you to mean "cull" as kill off the less desirable individuals, and "positive breeding program" as only allow the more desirable to breed, then there wouldn't be any difference in result, surely? And if not, then what DO you mean by each?
     
  8. Oct 22, 2006 #7

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    A positive breeding would be, if say you want to increase the height of the population, you give the taller people tax breaks for marrying each other and more breaks the more kids they have but using the same techniques you discourage short people from marrying each other or having children. The problem is that this is a very slow process and many of the children of the tall people will not be remarkably tall, while some of the children of short parents which you're trying to discourage will be taller than average.

    Culling would be biologically intervening to make short people infertile.
     
  9. Nov 4, 2006 #8
    Genius can be learned. Genetic predispostions towards genius obviously bypass the need for this learning process. But you give me a person of average IQ, say 110, and after a year of training, they will be a genius. Training entails: mnemonics, rapid math, pattern recognition and baring to conscious one's unconscious thoughts and the triggers which link them.
     
  10. Nov 6, 2006 #9

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    I don't believe it. There have been hyped programs with claims like these for decades, but results have been few and far between. I recall "Sylva Mid Control" which ensnared some of my workmates back in the seventies. If somebody says they can produce geniuses, let them produce the geniuses. Most people don't know what intelligence really implies and are snowed by simple meorization tricks.
     
  11. Nov 6, 2006 #10
    I can certainly understand your skepticism. I would certainly not consider mnemonics the sole tool used to create genius. But it is the foundation by which all else is learned. Creativity and pattern recognition are then developed upon this, but first you must be able to memorize facts rapidly and then the formation of linkages between them can be instituted.

    This is too large a topic to cover on a message board, so I'll give one micro example of pattern recognition: You may notice that people scratch their temple, or scratch their nose, or scratch behind their ear. This is a common human trait that we'd otherwise just think of as an itch. But there are reasons why we scratch an itch. As you read this right now, I guarentee you have at least spot on your body that itches, but until I mentioned this, the itch was relegated to your subconscious. You see, we start to scratch an itch at the beginning of a thought, or the end of one. Try this if you don't believe me. Sit down at a coffee shop and read a book. As a person walks by you, but before they are completely by you, look up at them suddenly. You will notice that they immediately or nearly immediately scratch an itch. Now, everytime you have an itch that you just realized you scratched, ask yourself, why did I scratch it all of a sudden? And what emotion/ train of thought caused me to scratch it? You may even notice that you scratch different areas of your body based on different emotions/ trains of thought. This is a simple example of how bringing to mind one's unconscious actions can allow you to recognize the same pattern of thought in another person that made them do an unconscious action.

    There are tons of little tricks like this that you can use to read a person's mind. This is one of the most basic, but other allow you to detail their thoughts more precisely.

    Another trick is the 50/50 stare where a person is interested in keeping tabs on you but is afraid to make eye contact with you. This person will look nearly straight forward, but will have you just inside of their peripheral vision. Even dogs do this!

    Another trick is the fake ear scratch, where a person who wants to stealthy look at you on their left, pretends to scratch their right ear. Because scratching your right ear, naturally brings your head to a right tilt, its easier for them to look at you and makes it look like they are simply itchy.

    Another is the false sniff. Someone without a cold sniffs for no reason as they think about you.

    Another is the false grunt. A male is threatened by you and pretends his throat needs clearing when it does not. He is vocalizing his presence in some sort of vestigial primate sociology he is not aware of.

    To practice learning these tricks and many others, take notice of what people do when they walk by you on a street. Especially eyemovements and how quickly they move over to their side of the sidewalk, how early they do, if they pretend to be interested in the houses until the last moment and then they look at you for 1 second, etc. There are dozens of mannerisms in this simple interaction that can tell you much about a person's fears, anxieties, confidence, etc.

    There are dozens more... People think reading minds is some mystical psychic realm, but the fact is its a science and humans are hardwired with archetypal body languages that they are not usually consciously aware of.
     
  12. Nov 7, 2006 #11

    selfAdjoint

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    Cold reading, which is the set of tricks you are reporting here, has nothing to do with deep thought, genius, or creativity. This is typical of the misunderstanding I spoke about iin my last post. People of average intelligence can't even imagine what genius is, so they're suckers for some four-flusher (not describing you, CHaos!) with a bag of fake goodies.
     
  13. Nov 7, 2006 #12
    Fair enough. Can you define genius for me then, I'm not sure what it entails in your opinion.
     
  14. Nov 7, 2006 #13
    You can train someone to be a genius in a year? How much does it cost?
     
  15. Nov 8, 2006 #14
    You can also be trained to be an olympic marathon runner, but the question is would you commit every waking hour in training to do so?
     
  16. Nov 8, 2006 #15

    selfAdjoint

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    Well I can cite Freeman Dyson's opinon on Richard Feynman. Dyson you must understand was extremely smart, a mathematician who converted to physics and did an awful lot of the heavy lifting associated with unifying the Schwinger-Tomonaga and the Feyman versions of QED and working out the consequences of their introductory thoughts. The theory QED as we have it is largely from the hand of Dyson. (A good source for Schwinger, Tomonaga, Feynman, and Dyson is Schweber's QED and the Men who Made It[//i])

    So Dyson said (this is my recollection, but true to the spirit): With many thinkers I can imagine being that smart. I can say to myself if I was x percent smarter I could do what that person does. But with Feynman I can't do that; I can't even imagine thinking like Feynman. He seems to think along different paths or by different laws than anything I can imagine.

    So it is with mathematics. There are creative people of all abilities, but at the top are people practicing a different order of thought.
     
    Last edited: Nov 8, 2006
  17. Nov 9, 2006 #16



    Well I can certainly appreciate that Feynman was a genius, possibly on par with Einstein. That paraphrasing of Dyson saying that Feynman's thinking was beyond his comprehension is doubly interesting since Dyson himself was a genius. This would make Feynman a supergenius. I'd like to know how you would characterize genius though. Are there a set of attributes or abilities that geniuses possess? Forget about Feynman genius, but how about an average genius.
     
  18. Nov 9, 2006 #17
    No, and I doubt training every waking hour would make me a world class olympic anything other than a world class physical wreak. No doubt, 'wanting to' will get you part of the way, but talent separates the very best from all us ordinary folks. And 'us ordinary folks' are just about all of us IMO. I suspect that olympic level marathon runners possess a certain personality, a psychology that allows them to go out on those long runs and not give in after a couple of months or years (or miles in my case). So maybe a certain underlying personality structure is a prerequisite. I'd also think that in addition to personality, you might have to also fit into a certain age group if you expect to eventually be world class. Bodies tend to break down as the years go by and if you're expecting to compete at the highest levels you'd better be there yourself. Then you might expect a certain body type, there's a lot of pounding going on during all of that training. The less pounding the less chance for injury I'd think. I'm not looking just for a great set of lungs -- but a good heart also. So you'd have to include a body and mind that is in excellent physical health prior to training. No nagging pre-existing conditions, no hidden, latent injuries, no weak wills. What doesn't break you makes you stronger -- etc. And being world class means doing all that, being all that, and still having the ability to outrun those other folks that are 'all that'. Don't know guy, I just think sometimes there's more to this than merely wanting to do it.
     
  19. Nov 10, 2006 #18

    You are arguing that what seperates a world record holding marathon runner from an ordinary marathon runner is their genes. What I am saying is that nurture far supasses nature in the development of (in this case) a marathon runner. Nurture is the equalizer.
     
  20. Nov 10, 2006 #19

    selfAdjoint

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    And just what is your evidence for claiming that? This is not the general discussion forum and bare opinions about matters of fact are not in order.
     
  21. Nov 11, 2006 #20

    Fine. Lock this thread and discard it.
     
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