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How to Raise Our I.Q.

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Re: How to Raise Our I.Q.

#21
post #18

Earlier quoted context omitted.

socially repugnant has nothing to do with science. the data says parent IQ is highly correlated with offspring IQ.

And the offspring are, expect in the case of adoption, in the same socioeconomic class as the parents.

I certainly hope that somebody publishes any adoption studies of twins several decades ago and several other studies replicate the results, so we'll know if you made a relevant point.

Re: How to Raise Our I.Q.

#22

Earlier quoted context omitted.

socially repugnant has nothing to do with science. the data says parent IQ is highly correlated with offspring IQ.

data says parent IQ is highly correlated with offspring IQ What's the significance of that in relation to the book review submitted here?

That a better way to raise average IQ is to encourage smart people to breed?

Re: How to Raise Our I.Q.

#23

Earlier quoted context omitted.

data says parent IQ is highly correlated with offspring IQ What's the significance of that in relation to the book review submitted here?

That a better way to raise average IQ is to encourage smart people to breed?

a better way to raise average IQ is to encourage smart people to breed?

That's an interesting hypothesis, but the effect size of environmental changes is MUCH larger than the effect size of changing gene frequencies in increasing the IQ scores of the general population. It has been typical for decades for authors who take a strongly hereditarian (which means "pre-Mendelian," really) view of influences on IQ to suppose that IQ score trends over time would be for the population mean to decline. In fact, population trends over time in countries all over the world have been HUGE increases in IQ.

The Stanford University researchers who developed the first few versions of the Stanford-Binet IQ tests had access to data for decades that could have revealed a surprising trend in raw item content performance on IQ tests. The trend, now known as the Flynn Effect, after Professor James R. Flynn, who had the greatest role in discovering it, is that raw scores on IQ tests, including all kinds of IQ tests loaded on fluid intelligence, have risen over time in national populations all over the world.

James R. Flynn started slowly but worked steadily in finding data sets and eventually found a large body of tests for which raw score data is available over long time series. His first published paper (1984) on the issue of IQ score changes over time was based on the renorming of the most commonly used IQ tests in the United States. He found that as new editions of the major IQ tests (the Wechsler test and the Stanford-Binet) were published, that the newer edition of each test invariably had a norming sample population that did better on the old edition's item content than had the old edition's original norming sample population. In other words, for a given brand of IQ test, as time went on, the average person did better and better on the raw item content of that test, resulting in higher and higher IQ scores over time for people tested on the same test with score calculation based on the earliest norms.

The possibility that raw scores on IQ tests were rising so consistently, and in such magnitude, was so surprising that it prompted many psychologists to cast doubt on the sample populations used for the early studies that showed this phenomenon--even though those sample populations were none other than the norming sample populations for the major brands of IQ tests. Psychologist Arthur Jensen proposed to James R. Flynn in January 1983, while Flynn's first major article on score trends was awaiting publication, that a good data set to show changes in IQ scores over time should

a) be comprehensive, e.g., a test of an entire national population, to eliminate the possibility of sample bias,

b) use the same test from generation to generation, with time trends shown by raw score differences,

c) emphasize "culture fair" tests such as Raven Progressive Matrices, which were presumed then not to include item content that is taught by compulsory schooling,

d) be based on adult populations, who have reached a mature level of intellectual functioning, to minimize the effect of differing rates of intellectual growth in childhood from one generation to the next.

Amazingly, Flynn found data sets with all of those characteristics, especially data sets from compulsory IQ testing of NATO draftees in the Netherlands, Belgium, and Norway. The data based on a subset of items from the Raven Progressive Matrices test showed substantial raw score rises for Dutch draftees: if the 1952 population mean is taken to be IQ 100, by 1982 the Dutch male mean IQ was 121. The IQ raw score rise over time was smooth, and by the end of this period had resulted in ceiling effects on the test for a significant number of draftees (Flynn 1987). Flynn has suggested an experimental design that might help unravel the causes of the increase in raw IQ scores over time, while reviewing newly discovered data sets that extend observation of IQ score rises backward in time to the beginning of IQ testing. The Raven test, early in its use, was given to an age cohort born in the 1870s as part of a study of IQ changes over the course of adult aging. Careful analysis of this cohort allows extending IQ raw score trends back to the beginning of IQ testing, showing that fully 90 percent of Britons born in 1877 scored below the fifth percentile of Britons born in 1967, or in other words that most turn-of-the-last century Britons had an IQ of 75 or lower on a highly g-loaded IQ test, according to current norms (Flynn 1999; Flynn 2000b).

As Mackintosh (1998, p. 104) writes about the data Flynn found: "the data are surprising, demolish some long-cherished beliefs, and raise a number of other interesting issues along the way."

CITATIONS:

Flynn, James R. (1984). The Mean IQ of Americans: Massive Gains 1932 to 1978. Psychological Bulletin vol. 95, pages 29-51.

Flynn, James R. (1987). Massive IQ Gains in 14 Nations: What IQ Tests Really Measure. Psychological Bulletin, vol. 101, no. 2, pages 171-191.

Flynn, James R. (1998). IQ Gains over Time: Toward Finding the Causes. In Neisser, Ulric (Ed.). The Rising Curve: Long-Term Gains in IQ and Related Measures. Washington, DC: American Psychological Association.

Flynn, James R. (1999). Searching for Justice: The Discovery of IQ Gains over Time. American Psychologist, vol. 54, No. 1, pages 5-20.

Flynn, James R. (2000a). IQ Gains, WISC Subtests and Fluid g: g Theory and the Relevance of Spearman's Hypothesis to Race. In Gregory Bock, Jamie Goode & Kate Webb (Eds.), The Nature of Intelligence (Novartis Foundation Symposium 233) (pp. 202-227). Chichester, United Kingdom: Wiley.

Flynn, James R. (2000b). IQ Trends over Time: Intelligence, Race, and Meritocracy. In Kenneth Arrow, Samuel Bowles & Steven Durlauf (Eds.). Meritocracy and Economic Inequality (pp. 35-60). Princeton: Princeton University Press.

Mackintosh, N. J. (1998). IQ and Human Intelligence. Oxford: Oxford University Press.

Re: How to Raise Our I.Q.

#24
post #19

Really? I only ever thought of IQ as a measurement of elitism, not intelligence. I've met some really smart guys with IQs much lower than you'd expect, and dealt with some really stupid higher IQ folk.

I've met some really smart guys with IQs much lower than you'd expect, and dealt with some really stupid higher IQ folk.

This accords with my experience after fifty years of life, but is not quite a proof that IQ is meaningless. IQ tests estimate a kind of abstract problem-solving ability useful for many real-world tasks, and correlated with life success in various occupations. But IQ is not the same as rationality,

http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...

http://www.amazon.com/What-Intelligence-Tests-Miss-Psycholog...

or, if you prefer this terminology, IQ is not the same thing as wisdom,

http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=978...

http://www.amazon.com/What-Intelligence-Beyond-Flynn-Effect/...

so it shouldn't be terribly surprising to see irrational or unwise behavior from high-IQ individuals, as I certainly have.

Re: How to Raise Our I.Q.

#25
post #7

"If intelligence were deeply encoded in our genes, that would lead to the depressing conclusion that neither schooling nor antipoverty programs can accomplish much." More optimistically, it means that they're already working pretty well. In a chaotic environment where smart people are likely to be randomly struck down, most variation in intelligence is environmental: The smartest are those who avoid malnutrition, neo…

Another reply in this thread cites some of the research on IQ score trends over time. There probably is more gain yet to be had among disadvantaged populations than among advantaged populations (which have already enjoyed huge gains), but the mechanism of causation of IQ gains is unclear enough that there may yet be a lot of room for increase for all populations.

Even if IQ gains grind to a halt in particular places, there is still much to be done to raise the level of rationality in the population there. (Another reply to this thread just cited Keith Stanovich's recent book What Intelligence Tests Miss,

http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...

which is all about how to improve rationality among people of various IQ levels.) And for general social improvement, it is also possible to shape public policies so that they take into account common forms of human irrationality,

http://www.amazon.com/Nudge-Improving-Decisions-Health-Happi...

so that daily life is more sound even if the people living it are neither more intelligent nor more rational.

Re: How to Raise Our I.Q.

#26
post #19

Really? I only ever thought of IQ as a measurement of elitism, not intelligence. I've met some really smart guys with IQs much lower than you'd expect, and dealt with some really stupid higher IQ folk.

As much fun as it is to decry high IQs as the sole purview of snotty brats who can't actually amount to anything in the real world, it is still nothing but a combination of sour grapes and a biased sample. You notice the brats, you don't notice the high-IQ people that aren't snotty brats.

Science says that A: IQ clearly doesn't measure "real intelligence" B: Whatever "real intelligence" is, IQ does correlate with it fairly highly (as well as a number of other measurements), though you must understand what "correlate" means to fully comprehend that and C: real intelligence has real impacts on your real life, no matter how wonderful or awful that may sound.

It's real. The science is strong. The science is much more complicated and nuanced than most people understand, or, more profound, than most people want to understand. If you want to really understand the world, dismissing IQ is not a good start. (Nor is putting it on a pedestal, of course. If you want to understand the real world, recognizing that there is ground in between is also pretty helpful.)

Re: How to Raise Our I.Q.

#27

Earlier quoted context omitted.

That a better way to raise average IQ is to encourage smart people to breed?

a better way to raise average IQ is to encourage smart people to breed? That's an interesting hypothesis, but the effect size of environmental changes is MUCH larger than the effect size of changing gene frequencies in increasing the IQ scores of the general population. It has been typical for decades for authors who take a strongly hereditarian (which means "pre-Mendelian," really) view of influences on IQ to suppos…

the flynn effect has leveled off and shows signs of starting to reverse in industrialized nations.

Re: How to Raise Our I.Q.

#28

Earlier quoted context omitted.

socially repugnant has nothing to do with science. the data says parent IQ is highly correlated with offspring IQ.

Is the correlation more father --> son than father -->daughter? Is there a mean effect between parents? Which sex is the most dominant in passing along this trait? Are there any instances of the child having a greater than the average or either parent? That would be very interesting data.

Are there any instances of the child having a greater than the average or either parent?

There are many such instances. And there are instances of children having lower IQ scores than either parent.

More important, it is a rare case when the same individual has the same IQ score over the course of life. IQ can change over the course of life quite a lot. And any two brands of IQ test will not agree entirely in how they sort a group of test-takers into a rank order. And IQ scores don't tell the whole story about all the meaningful mental abilities that a learner has, as Lewis Terman (the first developer of IQ tests in the United States) was very honest about pointing out:

"There are, however, certain characteristics of age scores with which the reader should be familiar. For one thing, it is necessary to bear in mind that the true mental age as we have used it refers to the mental age on a particular intelligence test. A subject's mental age in this sense may not coincide with the age score he would make in tests of musical ability, mechanical ability, social adjustment, etc. A subject has, strictly speaking, a number of mental ages; we are here concerned only with that which depends on the abilities tested by the new Stanford-Binet scales."

(Terman & Merrill 1937, p. 25)

Re: How to Raise Our I.Q.

#29
post #18

Earlier quoted context omitted.

socially repugnant has nothing to do with science. the data says parent IQ is highly correlated with offspring IQ.

And the offspring are, expect in the case of adoption, in the same socioeconomic class as the parents.

doing a regression analysis shows that while socioeconomic factors obviously play a role, they do not account for all, or even the majority, of the difference.

Re: How to Raise Our I.Q.

#30

Earlier quoted context omitted.

a better way to raise average IQ is to encourage smart people to breed? That's an interesting hypothesis, but the effect size of environmental changes is MUCH larger than the effect size of changing gene frequencies in increasing the IQ scores of the general population. It has been typical for decades for authors who take a strongly hereditarian (which means "pre-Mendelian," really) view of influences on IQ to suppos…

the flynn effect has leveled off and shows signs of starting to reverse in industrialized nations.

I'll accept "leveled off" regarding certain countries, having read Flynn's work, and I'll accept "starting to reverse" if you are only talking about crystallized intelligence, for the same reason, but do you have any current citations to a disfavorable trend anywhere in fluid intelligence?
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