tag:blogger.com,1999:blog-9430835.post2715811312822071861..comments2014-09-01T00:35:29.048-07:00Comments on Steve Sailer: iSteve: Regression toward the mean and Francis GaltonSteve Sailerhttp://www.blogger.com/profile/11920109042402850214noreply@blogger.comBlogger52125tag:blogger.com,1999:blog-9430835.post-70610237580641813072013-02-06T18:37:23.278-08:002013-02-06T18:37:23.278-08:00nlufd [url=http://www.salelouisvuitton-no1.com]lou...nlufd [url=http://www.salelouisvuitton-no1.com]louis vuitton handbags[/url] lwbjnm http://www.salelouisvuitton-no1.com uomsm [url=http://www.get-louisvuittonoutlet.com]louis vuitton outlet[/url] eggdhq http://www.get-louisvuittonoutlet.com qnkda [url=http://www.pick-louisvuittonoutlet.com]louis vuitton outlet[/url] pscowi http://www.pick-louisvuittonoutlet.com pwmg [url=http://www.foxlouisvuitton.com]louis vuitton bags[/url] nniicu http://www.foxlouisvuitton.com gycvx [url=http://www.lo-louisvuittonoutlet.com]louis vuitton outlet[/url] xjbcxq http://www.lo-louisvuittonoutlet.com szvmc [url=http://www.locheaplouisvuitton.com]louis vuitton outlet[/url] zblnal http://www.locheaplouisvuitton.com irmaAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-69004076828419645892013-02-02T22:02:25.421-08:002013-02-02T22:02:25.421-08:00Regression to the mean is seen in all kinds of cor...<i>Regression to the mean is seen in all kinds of correlated measurements, whether genes are involved or not. So explaining it in terms of genes is interesting, but mainly because it explains why inheritance of intelligence or height more or less follows this nice mathematical model...</i> <br /><br /><br />You've got it backwards. Regression to the mean is explained in terms of mathematics. But it is not mathematics. Gravitational attraction is explained using mathematics. But hopefully you would not say that gravitational attraction is an interesting something which is used to explain mathematical principles? <br /><br />We construct nice mathematical models and theories to help explain observed phenomena. (As Galton did with regression to the mean) The phenomena do not "follow" the mathematical models, not in any sense of the word "follow".Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-72890979412251360922013-02-02T20:28:04.785-08:002013-02-02T20:28:04.785-08:00Steve: Isnt that just another way of saying clone...Steve: Isnt that just another way of saying clones' and identical twins' traits are more strongly correlated than siblings' or parents'/childrens'? Twin studies tell us that much already, which is why cloning Albert Einstein will likely produce a very smart kid, but probably won't give you someone who will revolutionize physics the way Einstein did. <br /><br />Anon: Regression to the mean is seen in all kinds of correlated measurements, whether genes are involved or not. So explaining it in terms of genes is interesting, but mainly because it explains why inheritance of intelligence or height more or less follows this nice mathematical model. There isn't some explanation involving reessive genes that explains why the kids who did best on the first calculus exam will usually do a little worse on the second one, or why the mutual funds who get the best returns this year will usually not do as well next year. NOTAnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-40807506678044578972013-02-02T14:21:13.501-08:002013-02-02T14:21:13.501-08:00Maybe Steve needs to do a "genetics 101"...Maybe Steve needs to do a "genetics 101" column, because it strikes me that a lot of his readers are surprisingly hazy on basic high school biology level genetics.<br /><br />In particular the chapter on Recessive Genes needs attention.<br /><br />People are "carriers" for a vast amount of genetic information, only a faction of which is expressed in each of us as individuals. With respect to intelligence, there are large numbers of people who are not of unusually great (or unusually weak) intelligence themselves but who carry within them the genetic potential for great(er) intelligence. And/or for weaker intelligence.<br /><br />By the same token people of great intelligence - and of lesser intelligence - carry the genetic blueprints for making children of more "normal" intelligence. The operative word there is "carry". We are "carriers" for lots of traits which we do not manifest ourselves. A couples potential offspring could in theory exhibit any of a wide variety of states - different hair colors, different eye colors, different heights.<br /><br />Assume the existence of a normal Euro-American couple of somewhat above average attributes. He's 6'1", she's 5'7". They're both IQ 115. Both are slightly more attractive than average. Now assume that they have a lot of children - by which I mean 10,000 or so children. (We can do this in Theoretical Land)<br /><br />If we carefully study those 10,000 children we'd find that they display a <i>lot</i> of variety. Some will be much taller than Mom and Dad, others much smaller. Some will be much more intelligent than Mom and Dad, some much less so. But the average should be - excluding all environmental factors - pretty close to their parents.<br /><br />Pretty close, but somewhat less than. Less than, because their parents (being normal Euro-Americans) have normal Euro-American DNA. In the case of the parents that normal DNA happened to throw up slightly abnormal results (just as their own DNA as manifested in their 10,000 kids threw up some deviations from the norm) but their DNA is still such that its common or normal expression is of 5'10 men, 5'4" women, and people of IQ 100. So their children, on average, will be closer to that norm than their parents.<br /><br />We all have "active genes" and "latent genes". We all have an "active genetic IQ" and a "latent genetic IQ". Your active genes may give you a genetic IQ if 125, but your latent genes are what govern the probable IQ of your offspring, and they will point to a number less than 125.BK201noreply@blogger.comtag:blogger.com,1999:blog-9430835.post-84230291133221636842013-02-02T12:02:07.154-08:002013-02-02T12:02:07.154-08:00"Regression to the mean is a mathematical phe...<i>"Regression to the mean is a mathematical phenomenon, not a genetic one."</i> <br /><br /><br />It's both a mathematical and (within the context of this discussion of genetically determined traits) a genetic phenomenon. Mathematics is simply a language we use to describe various phenomena. Don't confuse that with mathematics <i>being</i> the phenomenon in question.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-64317973882922250012013-02-02T11:51:00.397-08:002013-02-02T11:51:00.397-08:00If you know my parents were smart, you should pred...<i>If you know my parents were smart, you should predict that I'm smart.</i> <br /><br /><br />No, I should not. There should be a degree of probability that you (and your siblings) will be smart. That probability is not going to be terribly high. It will be far less than a certainty or near certainty. Anyone who says "I predict that the offspring of these two smart parents will be smart" is simply revealing their ignorance of genetics.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-27367286282523121512013-02-02T11:17:40.287-08:002013-02-02T11:17:40.287-08:00"Regression to the mean is a mathematical phe..."Regression to the mean is a mathematical phenomenon, not a genetic one."<br /><br />Yes ... but ... sexual reproduction sees more regression toward the mean than asexual reproduction (cloning). That's why farmers want to clone their top producing specimens of livestock.Steve Sailerhttp://www.blogger.com/profile/11920109042402850214noreply@blogger.comtag:blogger.com,1999:blog-9430835.post-4145112011104900312013-02-02T09:10:04.997-08:002013-02-02T09:10:04.997-08:00Is there data that follows IQs from three generati...Is there data that follows IQs from three generations? <br /><br />If you know my parents were smart, you should predict that I'm smart. If you know my grandparents were smart, too, that should increase your estimate of my intelligence. Similarly, if you know my siblings are smart, that should increase your prediction about my intelligence. <br /><br />If someone has built up a regression model of this kind, it would be interesting to see, so we could put some numbers on this. Maybe we could get a reasonable first cut here by some kind of weighted average of ancestors? There must be a standard way of doing this....NOTAnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-64746176641147232542013-02-02T08:47:48.015-08:002013-02-02T08:47:48.015-08:00Re eugenics:
The dysgenic pattern of fertility we...Re eugenics:<br /><br />The dysgenic pattern of fertility we see now (smart women have fewer kids, later, than dumb women) is the result of people responding to incentives:<br /><br />a. Smart ambitious people mostly don't want to have kids till they're done with school and somewhat established in the world. It takes longer to do that if you become a doctor than if you become a waitress. <br /><br />b. Smarter people and people from better backgrounds tend to be better at making life choices like "should I be careful about not getting pregnant?" and "should I shack up with this exciting badass lowlife?" <br /><br />c. Smarter people are better at accomplishing what they set out to do, including using their birth control properly to avoid pregnancy.<br /><br />d. There are a lot of built-in incentives for or against having kids that are quite different at the top and bottom. Extra kids at the bottom may mean more government assistance (though not enough to cover the costs--single mothers of multiple kids are, as a group, dirt poor and struggling all the time), where at middle income and above they mean more expenses (private school or expensive house in a good school district, college, tutoring, braces, swimming lessons, summer camp) without more help. <br /><br />Some of the incentives can be reversed without any more coercion than is already in place. How about agreeing to a rise in the top tax rate if it is exactly offset in revenue terms by an increase in the per-child tax credit? This would benefit Republican voters, but not donors or think-tank owners, so the GOP probably wouldn't support it, but it would have a positive eugenic effect, as well as helping middle class families. How about simply making long-term easily-used birth control easy to get for everyone including the poor, with public service announcements pushing it? Anything that makes it easier for middle class people to get good schools at lower cost is similarly a win, as it decreases the cost of raising kids to middle-class standards. Fixing the student loan/tuition bubble so we stop having the marginal kids with no degree and big debts, and the medium-smart kids with a degree and a pile of debt, would also help. <br /><br />I think Steve's term for this is affordable family formation. Making it more affordable to have kids at middle class payscales and standards would be mildly eugenic. NOTAnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-19128451064221427582013-02-02T08:27:49.454-08:002013-02-02T08:27:49.454-08:00Regression to the mean is a mathematical phenomeno...Regression to the mean is a mathematical phenomenon, not a genetic one. That's why it works on IQ scores, test scores, racing times, performance flying, etc. It's just telling you how correlated numbers work. The underlying assumption is that the two variables (say, father's' height and sons' height) each fall on a normal distribution, and there is a linear relationship between father's height and the mean of his sons' height. Regression to the mean just says that if my dad is +1 sigma, the mean of his sons' distribution is less than +1 sigma but more than the sons' average. <br /><br />Suppose my father is exactly of average height. Then your knowledge about my height is a bell curve centered on the average of the sons' height distribution. That is, if you needed to make a bet about my height, you could do no better than to use the probability tables from a normal distribution. If someone wants to know how likely it is that I will be 6'5", if you know the mean and standard deviation of the sons, you can calculate that probability. <br /><br />Now, suppose you move my father to +1 sigma--one standard deviation above the fathers' mean. What do you know about my height? It's also a bell curve, but the center of it--the mean--is moved a little to the right. All regression to the mean says is that you move the center of my bell curve, but by less than one sigma to the right. That's it. <br /><br />So, if my dad is 6'3", you should bet on me being taller than the average, but not as tall as he is. Sometimes, you will lose that bet, but it's the best one you can make. And this all has to add up so that we see the distributions of fathers and sons thst we already know.<br /><br />Imagine that we separated all the fathers into people above and below the average, and gave each father exactly one son. If there are any tall sons of short fathers, then there *must* be some short sons of tall fathers, just to make the numbers come out right. The fact that short men can have tall sons means that tall men must be able to have short sons. That's the key insight into regression to the mean--upward mobility (sons who are taller or smarter than their dads[1]) requires downward mobility (sons who are shorter or dumber than their dads).<br /><br />[1] This has to be true in terms of rankings among fathers and sons. If everyone is getting smarter or taller thanks to nutrition or something, then most sons will be taller than their fathers, but some shorter than average men will have taller than average sons, and some smarter than average dads will have dumber than average sons, and so on. NOTAnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-10762995047066749382013-02-01T03:33:52.907-08:002013-02-01T03:33:52.907-08:00"Low IQ kids could be offered various incenti..."Low IQ kids could be offered various incentives."<br /><br />That's the point though - tricking people into trading something priceless for something of only nominal value. Practically speaking you maybe right but i don't think that kind of society is likely to be pleasant.<br /><br />Now tricking low IQ people into sterilization *after* one or two kids is something else.<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-49324014103372129912013-01-30T20:54:37.840-08:002013-01-30T20:54:37.840-08:00Eugenics does not have to be forcible. Voluntary p...Eugenics does not have to be forcible. Voluntary programs in India caused many thousands of men to get vasectomies for a transistor radio, for instance. Low IQ kids could be offered various incentives.<br /><br /> Sterilization could also be made a condition of parole for certain offenders. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-5678377520470454852013-01-30T05:20:08.167-08:002013-01-30T05:20:08.167-08:00"where a 160IQ is a 1 in 10000 4sigma score.&..."where a 160IQ is a 1 in 10000 4sigma score."<br /><br />a 1 in 30,000 score apparently.<br />1 in 10000 corresponds to roughly 3.72sigma.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-9521111897397412622013-01-30T05:16:10.357-08:002013-01-30T05:16:10.357-08:00"I think it implies that it's not just th..."I think it implies that it's not just the genes themselves but also whether they get expressed or not? So a family might pass down the same genes but which ones are set to on or off has a random element?"<br /><br />Doh.<br /><br />Or as someone mentioned on another thread - recessives.<br /><br />dumb of me not to think of that.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-46267105911953442982013-01-30T01:41:00.421-08:002013-01-30T01:41:00.421-08:00"The best kind of eugenics for a pleasant soc..."The best kind of eugenics for a pleasant society is negative: weed out the idiots and destructive people via sterilization."<br /><br />I don't think you can have a pleasant society where people are forcibly sterilized when they haven't done anything.<br /><br />A strict (but sensibly designed) criminal justice policy would allow a person's own actions to decide their reproductive potential.<br /><br />(Necessarily combined with a strict but sensible immigration policy.)<br /><br />.<br />"Isn't that the kind of "breeding" the upper and upper-middle classes of Britain practiced for centuries? The aristocracy certainly thought of itself as -- and perhaps was -- "smarter, healthier, and handsomer" than the commoners."<br /><br />Not really. They were standard arranged marriages based on wealth and status so with almost no direct selective element at all except when a rich man married a non-rich beauty.<br /><br />The real selective mating in England was among the middle strata that eventually produced the Franklins and the Darwins.<br /><br />.<br />"My brain is old and creaky, but isn't the reason regression to the mean doesn't doesn't lead to everyone being dead average is because sheer chance produces individuals who are far from the mean?"<br /><br />I think it implies that it's not just the genes themselves but also whether they get expressed or not? So a family might pass down the same genes but which ones are set to on or off has a random element?<br /><br />.<br />"I find it surprising that the average chest size of a bunch of Scottish soldiers in the early 19th century was 40 inches."<br /><br />Mountain lungs?<br /><br />.<br />"Finally, why do you want to select for IQ?"<br /><br />Agree. Select for IQ at the bottom and health at the top.<br /><br />.<br />"The millions of above average but not brilliant folks have much lower probability of producing einsteins, but their numbers make sure they make up the remaining 43/44. If they are reproducing of course."<br /><br />Yep. Increase the mass in the middle and they'll produce all the outliers you'll need.<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-42748699166212058072013-01-29T23:55:42.006-08:002013-01-29T23:55:42.006-08:00Suppose there are 10,000 normal people, 100 stupid...<i>Suppose there are 10,000 normal people, 100 stupids and 100 geniuses in a population. Regression towards the mean tells us most of the children of the geniuses will be normal. Assume 90% of their children will be normal. Also, regression towards the mean will say 90% of the kids of the stupids will be normal.<br /><br />There is also natural variation, so not all the kids of the normals will be normal. In this example, let's say 0.1% of the kids of the normals will be geniuses and 0.1% will be stupid. (The reason for the choice of number will be clear soon)<br /><br />Also, assume the population is just replacing itself, with no difference in fertility. Then the number of geniuses in the next generation will be:<br />90%*100 +0.1%*10,000 = 90 + 10 =100</i><br /><br />You meant "0.9%", and "10%*100 +0.9%*10,000 = 10 + 90 = 100".<br /><br />Holt's description is pretty good, but I know that I had to spend a bit of time figuratively putting pencil to paper a few years ago to properly understand this concept, so I expect most other people will have to actually reproduce a bit of math as well. I'll provide a few more guideposts here.<br /><br />(The following assumes that IQ has mean 100 and standard deviation 15, and everything can be accurately described by simple Gaussian distributions. This is not actually true, but once you master the basics you have a much better shot at effectively modeling reality's messier bits.)<br /><br />First, consider the two extreme cases:<br />1. Zero additive heritability among humans. Then everyone can be said to have a "genetic IQ" of 100 by virtue of being human, and all observed IQ variation among living people has nothing to do with "genetic IQ".<br /><br />2. Near-100% additive heritability. In this case, the "genetic IQ" distribution is essentially synonymous with the actual IQ distribution, and everyone's IQ is very close to the average of their parents'.<br /><br />The reality is, of course, in between. One less obvious, but crucial, consequence of this is that the distribution of "genetic IQ" is SIGNIFICANTLY NARROWER than the distribution of actual IQs. For example, if additive heritability is 64%, the "genetic IQ" distribution has a standard deviation of 12 (i.e. sqrt(0.64) * 15), rather than 15: <b>a person with a "genetic IQ" of 148 is as rare as a person with an actual IQ of 160</b>. (This is why almost everyone with 160 IQ has to be both lucky AND have good genetics.) In this case, adding standard-deviation-12 "genetic IQ" to standard-deviation-9 "luck" produces standard-deviation-15 actual IQ.<br /><br />If you know nothing about a 160 IQ person's ancestry, your best estimate of their "genetic IQ" (assuming 64% additive heritability) is 138.4; you'd expect them to benefit from a hefty 21.6 luck points. (Recall that, if additive heritability was zero, they'd be benefiting from 60 luck points; so it makes sense for this number to scale linearly with heritability.) So if two such people marry, you'd expect their kids to cluster around 138.4. But if these kids marry other "regressed kids of 160 IQ parents", there will be no further regression to the mean. These folks are clustered around 138.4 "genetic IQ" and zero bonus points from luck, so they will tend to breed true.<br /><br />Similarly, if you know 160 IQ person A's parents also averaged 160 IQ, your estimate of person A's "genetic IQ" should be significantly higher than 138.4. (How much higher is a question for Bayes' theorem and a computer.)<br /><br />Depressingly, this logic justifies very un-American attitudes toward class and race, at least when it comes to marriage. Instead of trying to shut it down, progressives should really be trying to push human genetics research forward as quickly as they possibly can, because that's the only real way to render the old attitudes obsolete.DoJnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-82842187303662316312013-01-29T22:36:06.604-08:002013-01-29T22:36:06.604-08:00Sorry about that, I wrote the example wrong. You n...Sorry about that, I wrote the example wrong. You need 0.9% of the normals to have genius kids, and 0.9% stupid kids.<br /><br />Then the number of geniuses in the next generation will be<br />10%*100 + 0.9%*10,000 = 10 + 90 =100Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-91529473879424119242013-01-29T22:27:43.739-08:002013-01-29T22:27:43.739-08:00@jody
"without additional mathematical princi...@jody<br />"without additional mathematical principles fleshing out and expanding on the ideas here, the math, as presented, does absolutely, positively posit that all the very smart people will decline into relatively average people after a few generations. at every IQ SD step, the math says, you lose IQ points when you reproduce."<br /><br /><br />Here is some math to explain what is going on. I will just simplify things by assuming there are three groups of people, the geniuses, the normals, and the stupids. How it generalizes to the case of continuous variation will hopefully be clear.<br /><br />Suppose there are 10,000 normal people, 100 stupids and 100 geniuses in a population. Regression towards the mean tells us most of the children of the geniuses will be normal. Assume 90% of their children will be normal. Also, regression towards the mean will say 90% of the kids of the stupids will be normal. <br /><br />There is also natural variation, so not all the kids of the normals will be normal. In this example, let's say 0.1% of the kids of the normals will be geniuses and 0.1% will be stupid. (The reason for the choice of number will be clear soon)<br /><br />Also, assume the population is just replacing itself, with no difference in fertility. Then the number of geniuses in the next generation will be:<br />90%*100 +0.1%*10,000 = 90 + 10 =100<br />Which is exactly the same as the first generation. You can also see the the number of normals and stupids is the same in the next generation.<br /><br />The reason this happens is because there will always be more people closer to the average, so even if a small fraction of their kids move far from the average, this will be enough to keep their numbers stable.<br /><br />The situation would stabilize eventually no matter what numbers I picked. To see how this happens, see the wikipedia article on the eigenvalue problem.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-51049876906237344232013-01-29T21:51:25.361-08:002013-01-29T21:51:25.361-08:00No one here seems to understand tha the use of the...No one here seems to understand tha the use of the phrase "regression to the mean" here is precicely equivalent to the definition of a time-invariant random variable. The use of families or the subsequent test takers in the wiki link are irrelevant in that subsequent measurements are, by definition, independent of previous ones. That isn't true of red noise of course, which doesn't regress to a mean.<br /><br />I mean come on. Think about how stupid that wikipedia example is. The top 10% of random guesser are chosen to ... randomly guess again??? <br /><br />Of course in the real world, test takers don't guess. And genes are passed along. Obviously a the probability distribution of a child's IQ is a function of his parents (and their parents and their parents).JeremiahJohnbalayanoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-78575153073273729082013-01-29T21:21:36.404-08:002013-01-29T21:21:36.404-08:00without additional mathematical principles fleshin...<i>without additional mathematical principles fleshing out and expanding on the ideas here, the math, as presented, does absolutely, positively posit that all the very smart people will decline into relatively average people after a few generations. at every IQ SD step, the math says, you lose IQ points when you reproduce.</i> <br /><br /><br />There is no "math, as presented".<br /><br />For the umpteenth time, the principle of regression to the mean <i>does not say what you think it says</i>.<br /><br />It certainly does not say that "all the very smart people will decline into relatively average people after a few generations". I'm reasonably certain that after a few generations all the reasonably smart people of today will be, you know, dead.<br /><br />Regression to the mean does tell us that the descendants of todays very smart people will be less intelligent on average than todays very smart people. But - and here is the point which continually eludes you - that has no impact on the size of the right side of the overall populations IQ curve, because other high IQ people are always being born to parents of lesser IQ.<br /><br />Their descendants in turn will regress to the mean.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-4707857686576491032013-01-29T21:05:57.409-08:002013-01-29T21:05:57.409-08:00we never observe a linear increase in the number o...<i>we never observe a linear increase in the number of people in the very smart to genius range, derived strictly from population growth, ESPECIALLY in the third world</i> <br /><br /><br />Damn, son, it's like you're being deliberately stupid. Alas, I suspect you're just naturally stupid.<br /><br />Yes, we would expect that - all else being equal - the number of people who are at "genius" level of intelligence would increase with the size of the overall population. And yes, this does happen. It even happens in the Third World! Why you think it doesn't happen is just one more of the mysteries of your thought processes, along with your curious notion that you're a brave free-thinker for not using capitalization.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-80981273688647808152013-01-29T20:24:29.520-08:002013-01-29T20:24:29.520-08:00 The best kind of eugenics for a pleasant society ... The best kind of eugenics for a pleasant society is negative: weed out the idiots and destructive people via sterilization.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-72947516383861955672013-01-29T19:15:42.536-08:002013-01-29T19:15:42.536-08:00Jody,
"precisely. so where are all the smart...Jody,<br /><br /><i>"precisely. so where are all the smart people coming from? until there is math which describes how that happens, this regression to the mean math does not accurately predict what we observe."</i><br /><br />If you read what other people posted here, you would know that regression to the mean does roughly predict what we observe.<br /><br /><i>"yet we NEVER observe this. we never observe a linear increase in the number of people in the very smart to genius range, derived strictly from population growth, ESPECIALLY in the third world. mexico produced no geniuses in 1900 and by 2000 it still had not produced any geniuses despite it's population exploding from about 15 million in 1900 to about 100 million in 2000."</i><br /><br />Bringing up Mexico is an entirely different issue. <br /><br />First, regression to the mean describes what takes place within a breeding population. Different breeding populations *may* have different means to regress to. There's no evidence that most Mexicans and most Americans, for example, revert to the same IQ mean. <br /><br />If that's the case, then you need to be careful about what mean you're measuring and what you're trying to deduce from it. Suppose the number of pygmies has quadrupled over the last half century. Does that mean the number of pygmies tall enough to play NBA basketball should also quadruple?<br /><br />Second, since you were not around to observe the number of geniuses in Mexico in the early 1900s, and I'm guessing you aren't well versed in Mexican high culture at the beginning of the twentieth century, how do you know that country hasn't produced a proportionate number of geniuses in relation to its growing population over the last hundred years? <br /><br />I'm guessing that you don't even know contemporary Mexico well enough to appreciate how many geniuses have recently been born within its borders. I certainly don't. If you do know, I'd like to know how.<br /><br />Third, you seem to assume that a person who tests as a genius (however defined) will inevitably become famous. But however you measure genius - whether it's eligibility for membership in one of the prestigious high IQ societies or some accomplishment that merits inclusion - most high IQ men and women either accomplish very little of note or they remain anonymous to all but a small number of peers in their fields. Some high IQ people's greatest accomplishment is their test scores.<br /><br />That kind of puts a crimp in your seat-of-the-pants analysis about failing to observe many geniuses in Mexico.Pincher Martinnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-9110218108992417232013-01-29T17:52:05.423-08:002013-01-29T17:52:05.423-08:00if thousands of 160 folks have 1/44 chance to prod...if thousands of 160 folks have 1/44 chance to produce a similar IQed kid, the odds are still much better than the normal population where a 160IQ is a 1 in 10000 4sigma score.<br />The millions of above average but not brilliant folks have much lower probability of producing einsteins, but their numbers make sure they make up the remaining 43/44. If they are reproducing of course.<br /><br /><br />btw interesting start to the article:<br /><br />"In the eighteen-eighties, residents of cities across Britain might have noticed an aged, bald, bewhiskered gentleman sedulously eying every girl he passed on the street while manipulating something in his pocket. What they were seeing was not lechery in action but science. Concealed in the man’s pocket was a device he called a “pricker,” which consisted of a needle mounted on a thimble and a cross-shaped piece of paper. By pricking holes in different parts of the paper, he could surreptitiously record his rating of a female passerby’s appearance, on a scale ranging from attractive to repellent. After many months of wielding his pricker and tallying the results, he drew a “beauty map” of the British Isles. London proved the epicenter of beauty, Aberdeen of its opposite."<br /><br />He would have got kanazawa'ed today.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9430835.post-15773596435967683162013-01-29T17:43:52.665-08:002013-01-29T17:43:52.665-08:00Most of the world seems to have a strange fascinat...Most of the world seems to have a strange fascination with LA's dark side. I think that goes a long way towards explaining Chandlers success. Jeffhttp://www.blogger.com/profile/16439323657060902346noreply@blogger.com