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Flynn's "discovery" and "increases mainly among the less able"

Flynn did NOT "discover" the increase over time. Thorndike (1975), for example, provides detailed documentation of the relative increases on sub-scales of the Binet and proffers a range of possible explanations that are still being touted today. Raven (1981), re-published in Raven (2000), demonstrated the increases on the Raven Progressive Matrices among young people in the UK. What Flynn did (using the RPM!) was demonstrate that the effect was almost worldwide, ie not confined to the US and UK, and draw attention to the implication that these scores had been subject to a massive, and previously unsuspected, environmental impact which had implications for the interpretation placed on cultural differences. What he failed to do, and still to some extent, fails to do in continuing to offer his "basket-ball" analogy, is recognise that whatever explanation is accepted has also to explain dramatic international increases in such things as height and life expectancy.

As to the increases being concentrated at the lower end, what the adult data re-published in Raven (2000) show is that, as Flynn suggested, the data, reported by many previous researchers, that had previously been interpreted as showing a decrease in many abilities with increasing age must be re-interpreted as showing that there has been a dramatic increase in these abilities with date of birth. On many tests this occcurs at all levels of ability. Thus there is now abundant evidence that it is not true that the increase has been concentrated in the lower end of the distribution (and there are, in fact, horrendous measurement problems involved in substantiating any such claim). Tall people have got still taller: the whole distribution has moved up.

Having cited this evidence, I am re-inserting the material that someone deleted at the beginning of this month. However, since it would overweight the introductory paragraph to refer to these other studies at this point I am confining the alteration to simply saying that Flynn drew general attention to the increase and its implications.

Huh. I've just noticed that there isn't even a reference to Flynn's publications in the entry! I've inserted a couple.

Raven, J. (2000). The Raven’s Progressive Matrices: Change and stability over culture and time. Cognitive Psychology, 41, 1-48.

Thorndike, R. L. (1975). Mr. Binet's Test 70 Years Later. Presidential Address to the American Educational Research Association.

Quester67 13:43, 31 October 2006 (UTC)

Cultural expansion

The reason for this is the spread of European culture. The "Flynn effect" is in effect a measurement of how rapid European culture is being spread worldwide and nothing more. It is just another form of European cultural imperialism. Set the stardards and have the power (guns and resource control) to judge everyone else by those stardards. --Shabaka Tecumseh —Preceding unsigned comment added by 68.96.209.46 (talk • contribs) 12:54, 26 October 2003

Except that it has also (or especially) occurred among white European populations (in Europe and the US). —Preceding unsigned comment added by 62.0.90.87 (talk • contribs) 23:49, 22 January 2004

The fact that the increase occurs especially in White European nations, could just be further evidence of the growth of a European cultural standard; that the unifying aspect of it becomes most readily apparent in the places where it is strongest to begin with. --Shabaka Tecumseh —Preceding unsigned comment added by 81.134.61.22 (talk • contribs) 17:57, 17 July 2004

I certainly appreciate your concerns, and the issue of cultural bias in IQ tests is a significant and important issue, however I don't believe it holds water here. First, as the disscussant above noted, the Flynn effect is in fact most pronounced in homogenous, white European cultures. Now you argue that this may be further evidence of the growth of a "European standard" but I think you would be hard pressed to prove that the Dutch (for example) are significantly MORE homogenous or European now than they were 40 years ago! Yet the Flynn effect is clear there....

A second and perhaps more compelling argument stems from the fact that the Flynn effect is, if anything, more pronounced when we assess people with tests that are the LEAST culturally biased. Psychologists have individually adminsitered IQ tests that are purely non-verbal and can be administered with no verbal directions to persons with no formal education. These tests apparently show the least cultural bias (e.g. differences between cultural/ethnic/racial groups are lowest on these tests) yet the Flynn effect is, if anything, stronger with them. Again, while cultural bias in testing is an important issue, it is not the core of the Flynn effect. —Preceding unsigned comment added by 65.34.133.19 (talk • contribs) 03:44, 27 April 2005

I've got to disagree. The rise shown by the Danes seems to have tapered off, and then started going backwards. This actually strongly supports Shabaka's point, as the cultural biases first boosted the Danish scores, then, as they became 100% homogenised and the biases in the IQ tests were slowly removed due to better understand of the subtle bias effects, they came to depress those same high scorers.

Another factor is repeated testing. If you keep doing IQ tests, your scores go up. One case in the US was decided along these lines. US law says that those who cannot understand what they did wrong may not be put to death, and it has been ruled that this is an IQ of below 70. Re-normalisation effects are an issue here, as are the repeated tests, as since the first test, where the guilty party scored just 68 (and was therefore safe from state execution) on the first tests, but who now scores around 75. Of course, the possible better nutrition in prison may have assisted, but it is most likely the repeated taking of IQ tests that caused the rise. http://thescotsman.scotsman.com/international.cfm?id=675512002 —Preceding unsigned comment added by 217.14.176.57 (talk • contribs) 13:44, 6 July 2006

Training

Could it be that more and more people are getting training in doing in doing IQ tests? I read somewhere that there is a noticeable increase in the result from the 1st test you take to the 3rd one. Probably you learn to think like the test or something. —Preceding unsigned comment added by 80.224.96.198 (talk • contribs) 13:44, 14 May 2004

I think that is true, people are learning the way of the tests. Once I came across the following question. Which one is the odd one out: Train, Plane, Steamboat, Car, Bus. Ok, Trains can only move on tracks, Planes can move in 3 dimensions, steamboats move in water, cars are small and buses have commercials all over them. So which one is it? In the end it was the car, but with no explanation. But after a few of these you can probably figure out what the test writers were thinking. I guess people are figuring out the mindset of the people who made the tests. —Preceding unsigned comment added by 213.39.143.47 (talk • contribs) 08:54, 16 May 2004

Remember, this is not an effect of the same people retaking the test, but changes in the average scores in a population across generations. I.E. If the 18 year olds averaged 100 on a test in 1948, the 18 year olds now might average 128 on the same test. Now perhaps we are all exposed to more testing, but remember, this effect has occured dramatically in even the last 20 years. Has the average persons exposure to standardized IQ tests changed that much since 1985? It's a puzzle... —Preceding unsigned comment added by 65.34.133.19 (talk • contribs) 03:27, 27 April 2005

On the question above, I think it'd be the car, because it is the only one that you yourself are in control of. I don't know about exposure to IQ tests (I think I've taken two or so...) but standardized testing itself has exploded, with many students taking multiple AP, SAT I/II, ACT and even graduation tests in only four years. —Preceding unsigned comment added by Finnegar (talk • contribs) 23:40, 24 January 2007

This, to me, is the greatest weakness of any IQ test which includes this sort of question. As a mathematician will tell you, there are an infinite number of ways to describe any finite series. More broadly, questions along the lines of "which doesn't belong," or "which is the next in the sequence," unless they are so simple as to be nondeterminitive, don't have "right" answers. Even the "best" answer is often considerably more subjective than the author of the test may think it is. —Preceding unsigned comment added by 71.194.183.199 (talk • contribs) 16:08, 8 July 2007

Exercising intelligence

Flynn himself does not believe this to be the case. It is conceivable that something about modern society (the greater need for abstract thinking, presence of computers, more visually-oriented culture) is responsible.

Other arguments aside for the moment, I would say that modern society's requirements could be considered a precise indication of how intelligence could increase over time. After all, if modern society required greater use of muscles, the additional exercise would automatically make a population more muscular. Or, more appropriately, our equivalent "fitness quotient" (FQ?) must be going down over time, as technology spreads throughout the world and allows us all to become more sedentary. It seems to me that Flynn's disbelief implies an underlying assumption that "intelligence" is necessarily some ill-defined genetic trait that couldn't change so quickly over just a few generations. --Jeff Q 08:17, 20 May 2004 (UTC)

Original research ?

I don't know if it has been emphasized by some scientist(s) but IMO :

- the expense in education in many third-world countries were considerable (I have no serious datas yet),

- the progress in communications is simply incredible : It's not a secret on Misplaced Pages that I spent some time in Burkina Faso around 1986. In 14 month I could phone my mother once! Just click on http://www.cenatrin.bf/ to verify that the volume of information you can exchange has increased. --Ericd 20:36, 25 Jan 2005 (UTC)

Only increasing the lower IQs?

"Comparison of the IQ distributions indicated that 1) the mean IQ had increased by 9.7 points (the Flynn effect), 2) the gains were concentrated in the lower half of the distribution and negligible in the top half, and 3) the gains gradually decreased from low to high IQ."

Is it correct though, that if the average IQ in developed countries is rising but the higher intelligence individuals are staying the same, than we would actually see the higher IQ scores coming down (because the IQ test is calibrated to the population average)? --Nectarflowed 21:58, 26 Jan 2005 (UTC)

Correct. For example, if you were to say, try to compare Isaac Newton's IQ with a modern day person, you would have to adjust one of the two scores, since the scores are relative to the population, and the population would have changed. You might find this intersting: . --maru 16:16, 2 May 2005 (UTC)

Standard deviation?

• "The average rate of rise seems to be around three IQ points per decade."

Does this apply to tests with a standard deviation of 15 or some other value? Could this be mentioned in the article text?

Thanks, nyenyec ☎ 05:13, 16 July 2005 (UTC)

Those are the most common tests for IQ, and are the ones that typically give an IQ result. You are right, it is not discussed explicitly, there is simply a great deal of implication that the gains are universal for any professionally administered intelligence test that is effective.--70.112.247.90 (talk) 21:44, 21 December 2009 (UTC)

Microevolution

I have read many articles about the Flynn Effect but no one seems willing to consider the possibility of natural selection as the cause. In this case it would be called Microevolution or small scale changes in gene frequency over small time scales. If we agree that higher intelligence strongly improves a person’s chance of career and financial success, why not consider the possibility that this extends to reproductive success? As evolution on this time scale would only change the distribution of existing genes and not create new ones, this would be entirely consistent with the Flynn effect being strongest at the lower end of the intelligence range. No new and improved “smart” genes are being created. Instead, existing “smart” genes are becoming more common. It is also possible that the reproductive benefits of intelligence are non-linear. I suspect that the bottom tier of the intelligence spectrum within each cultural group is significantly less successful in reproduction that every other tier. The key point here is that reproductive success would need to be examined within the context of cultural groupings.

While I have no proof that this is the primary cause of the Flynn effect, it seems almost impossible to avoid including it as at least a contributing factor. A hundred years ago the primary selective pressures on the human population were factors related to mere survival. Live was “nasty, brutish, and short”. Higher intelligence would have been of secondary importance. The measured beginnings of the Fynn effect approximately correspond to timeframe when infant mortality declined and overall life expectancy began to increase. This would have inevitably changed the mix of selective pressures on the human population. Datlas99 —Preceding unsigned comment added by 71.10.239.92 (talk • contribs) 01:07, 24 August 2005

This has been considered, however, lower than average IQ is actually of a reproductive advantage in modern societies. The fitness cost of high IQ and/or a college education are large, and thus the expection would actually be a slightly lower average IQ over the time period. --Rikurzhen 01:35, August 24, 2005 (UTC)

Can you cite a reference for this ? I'm think the way this subject was studied was critical to the conclusions that can be drawn. Stating that a lower than average IQ has a reproductive advantage only leads me to wonder how the populations were defined and how they stratified the I.Q. ranges. Think about this, the reproductive influence of I.Q. doesn't have to be linear across the entire I.Q. spectrum to have an affect. The gene frequencies for the entire gene pool can be moved by a strong selective pressure on a narrow segment. Has anyone looked at the reproductive success of the bottom tier of the I.Q. range? Datlas99 14:46, 24 August 2005

Eh? "Fitness cost" of high IQ and education? Where are you getting that from? A college education is financially an excellent investment, and smarter people live longer happier lives. Perhaps you are referring to how richer people tend to have fewer children, and education and IQ tend to lead to more money...? --Maru 04:26, 24 August 2005 (UTC)

Longer, happier lives, yes, but does that mean more children ? That's the only aspect that counts for evolution. See dysgenics. --Flammifer 08:03, 24 August 2005 (UTC)

No it doesn't, Flammifer. The assertion is dubious to begin with, as it contradicts the Flynn effect. Furthermore, the "only" effect that counts for evolution is whether or not alleles spread within the gene pool. Children numbers are almost irrelevant. It has yet to substaniated that being smart or going to college makes one reproduce less, indeed intuition would lead one to suspect that given that college is an excellent financial investment, it would lead to greater reproductive fitness, not less, and that such an effect could be significant, and not irrelevant due to other considerations, and that this is in accord with the very well supported/observed Flynn effect. --Maru 12:58, 24 August 2005 (UTC)

I'm not sure what you're reffering to with "The assertion is dubious to begin with" :-P

As for the number of children being irrelevant, mm, I'd have to question that. Seems to me that's the most common way of spreading alleles in the gene pool, though there are other strategies (helping your relatives spread their genes, making sure your children have kids too, etc.). Flammifer 15:15, 25 August 2005 (UTC)

What I meant was the whole Flynn efect is about the average populace getting smarter, no? So you're arguing that the stupider people should be outbreeding the smarter implies the populace average intelligence going down, not up. --Maru 21:51, 26 August 2005 (UTC)

That wouldn't be surprising if the Flynn effect did not represent a real change in average ability, which is a possible interpretation of the effect. It is also possible that both a positive effect and a dysgenic effect is occuring simulateously and the overall trend is upward. --Rikurzhen 22:27, August 26, 2005 (UTC)

Whoa there guys. Here's a paper along the lines of my claim about negative fitness from increased IQ: PMID 12267266. Feel free to do more literature searches. --Rikurzhen 22:09, August 24, 2005 (UTC)

Also, relative fitness is--of course--all we are able to measure. --Rikurzhen 22:12, August 24, 2005 (UTC)

Facts?

I think you are missing the point here: - Were are the facts that show that the IQ levels are really increasing? - Have the same IQ tests been used to proof this point? I have my doubts. —Preceding unsigned comment added by 196.25.255.242 (talk • contribs) 19:35, 5 September 2005

Well, I don't think anyone would even suggest doing the study without using the same IQ test, not when you are looking at so many hard to control variables. Thus, when the IQ scores go up, it can be pointed to that IQ scores have increased over time. Yes, it might be better guesswork, but there is a fairly strong correlation between IQ scores on IQ tests, and actual IQ. —Preceding unsigned comment added by 217.14.176.57 (talk • contribs) 13:55, 6 July 2006

Look at the article on IQ - there is no such thing as 'actual IQ', IQ is defined as the scores on IQ tests, compared to the scores of the general population. It is meaningless to claim (and impossible to ascertain) correlation between scores in tests and some imagined 'actual IQ'. Cederal 10:38, 23 December 2006

You should read Jensen's '69 article on intelligence. It's difficult to talk about a subject with people who don't know even the basics. You might also be interested in this:

http://www.udel.edu/educ/gottfredson/reprints/2003suppressingintelligence.pdf —Preceding unsigned comment added by 84.253.252.200 (talk) 10:58, 26 December 2007 (UTC)

Rise of IQ scores vs. rise of IQ test norms

The article is somewhat misleading. IQ scores cannot rise - they are periodically recalibrated to have an average of 100. The Flynn effect is the IQ test standards gettig higher and higher, ie. previous generations would have scored lower on today's tests and the current generation higher on earlier tests. I cannot find Flynn's article online, but its abstract is clear about this:

"Demonstrates that every Stanford-Binet Intelligence Scale, WISC, WAIS, WISC-R, WAIS-R, and WPPSI standardization sample from 1932 to 1978 established norms of a higher standard than its predecessor. The obvious interpretation of this pattern is that representative samples of Americans did better and better on IQ tests over a period of 46 yrs, the total gain amounting to a rise in mean IQ of 13.8 points."

--Tgr 22:04, 16 March 2006 (UTC)

A very misleading article which seems to ignore the fact that IQ scores are normalized. By definition, the average IQ score is 100 and doesn't "increase". The average general intelligence in a population may increase, or decrease, but the average IQ is always 100. I'm sure Flynn's papers aren't as sloppy about this as this article is. - Nunh-huh 02:47, 18 April 2006 (UTC)

The article is certainly incomplete, but your claims are incorrect. An IQ score is normalized to mean 100 based on a representative sample of maybe N=1000 people. The actual population mean will be something around 100, but not precisely 100. If some kind of relavent demongraphic shift were to occur after the normalization, then mean IQ would truly change. This change could be counter-balanced by re-normalizing against a new representative sample. However, this does not change the fact that the average scores did change. Only the renormalization complicates this. If you look at a graph of average scores per year, you'll see that scores were increasing relatively constantly between normalization years with sharp drops after re-normalization -- the Flynn effect. --Rikurzhen 03:27, 18 April 2006 (UTC)

On the contrary, my "claims" are correct. IQ is normalized so that the average score is 100, and when it varies from that value, it's time for it to be renormalized. The article confuses "Intelligence" with "IQ score". - Nunh-huh 03:54, 18 April 2006 (UTC)

The delay between renormalizations is quite a bit larger than your claim suggests, such that the effects of renormalization are highly noticable at the tails of the distribution. The article confuses "Intelligence" with "IQ score". Huh? The word intelligence occurs predominantly in contexts of questioning whether the changes in IQ associated with the Flynn effect refect a change intelligence. There are lots of things lacking in this article, but distinguishing IQ and intelligence doesn't seem to be one of them. --Rikurzhen 04:26, 18 April 2006 (UTC)

Basically, this is the issue: When it is stated that IQ test scores are rising, is it referring to the raw score or the adjusted score? Kurt Weber 13:31, 24 April 2006 (UTC)

I fail to see where anyone could get the idea that this is an issue. The Flynn effect points out that similar demographics taking the *same test* will rise over time, with the most recent groups generally scoring more highly on the test than those previously. This is not a hard concept to grasp. Similarly, more recent IQ tests have to be harder than older IQ tests in order to keep the recorded score for the same demographic at the 100 baseline on the new test, rather than giving the same rising result, which would lead to the newer test having a baseline of 105, for example. —Preceding unsigned comment added by 217.14.176.57 (talk • contribs) 14:01, 6 July 2006

It's clearly stated in the article - from this http://en.wikipedia.org/search/?title=Flynn_effect&oldid=332722598 edit: IQ tests are re-normalized periodically, in order to maintain the average score for an age group at 100. In fact, the necessity for this re-normalization provided Flynn with an initial indication that IQ was changing over time. The revised versions are standardized on new samples and scored with respect to those samples alone, so the only way to compare the difficulty of two versions of a test is to conduct a separate study in which the same subjects take both versions. Doing so confirms IQ gains over time. --70.112.247.90 (talk) 21:51, 21 December 2009 (UTC)

Grantees

Jensen's work outside of race and intelligence is quite highly regarded. 3rd party reprint It would be highly unorthodox to refer to the Pioneer Fund / accusations of Marxism or lysenkoism every time respected scientists like Jensen / Gould or Lewontin are mentioned.--Nectar 21:21, 20 June 2006 (UTC)

Gould and Lewontin are no longer relevent for this field. I do not oppose adding Marxist, if you so desire. The Pioneer Fund is relevant, when person connected to an advocay group is cited, then this should be mentioned.Ultramarine 22:26, 20 June 2006 (UTC)

A source is needed to connect their opinions about the Flynn effect to their receiving grants from the Pioneer fund. Without a source, it's a OR synthesis to put the two facts together to make an argument. --W.R.N. 21:02, 11 February 2007 (UTC)

Jensen as well as Rushton (mentioned) are not scientific in the field of intelligence! Articles of Kamin and Omari and many others are evidence for that. I would recommend deleting such "experts". 89.55.50.76 (talk) 14:05, 29 September 2009 (UTC)

My humble speculation on substantial causality of the Flynn Effect

Even as everything from soup (amino acids) to nuts (arginine) has been proposed as explanations for the Flynn Effect, I feel puzzled by what may be an overarching oversight by researchers and spectators: larger headed babies can now be born due to medical interventions---most notably and ubiquitously, the caesarian section. That procedure alone is, and has been for some time, routinely done worldwide. Homo sapiens’ pelvic capacity is generally acknowledged to be near its limit as for birthing a baby with a large cranium. Common sense dictates that many large-brained fetuses never made it into the breeding gene pool. Yet many who previously would not have made it, have been doing so within the general time frame of the Flynn Effect phenomenon. --Paul K. —Preceding unsigned comment added by 68.83.48.84 (talk • contribs) 02:44, 8 November 2006 When one considers that a sizable proportion of caesarians result from heads too large for the birth canal, then it's easy to imagine the number of larger-headed babies who've been born from this common intervention.. The correlation between cranial capacity and I.Q. is not large, but it is a substantive and positive one. Pelvic capacity has an upper range that could preclude an increase in birthable cranial circumference; with caesarian intervention, which is quite commonplace even in a Third-World or low socioeconomic milieu, this upper limit can now easily be breached. —Preceding unsigned comment added by 68.83.48.84 (talk • contribs) 02:28, 26 December 2006

A problem is that larger head doesn't mean smarter. I read a report some years ago that the average IQ had actually decreased over the years. 1851, before public education in the US, was actually the high point in literacy in the US. I believe most Americans score lower on IQ tests than at any time in the past - strange ( actually not really I suppose considering the political implications ) that we are evolving so fast according to Flynn. However, rises and falls in an IQ test means that it isn't actually measuring native abililty - what is it measuring? and is the test worth a hoot if it is really measuring daddy's wealth, food intake, school quality, etc. If IQ between siblings varies so much then how important is heredity - unless they have different fathers. —Preceding unsigned comment added by 159.105.80.219 (talk • contribs) 12:04, 12 December 2006

Large differences between sibling IQ indicates a high heritability. You only inherit 50% of your parent's genes after all. While brain size has a weak correlation to IQ, there's a correlation non the less, so Paul K's speculation might be correct. Also keep in mind that people have been getting taller, and taller people have larger brains. This is probably one of the contributors to the Flynn effect. And mankind is indeed dumbing down, there's research in that area that is listed in the dysgenics article. --Scandum 12:47, 12 December 2006 (UTC)

My humble speculation regading the main cause of the Flynn Effect

I feel puzzled by the fact that everyone seems to assume that the Flynn Effect is caused by an increase in people's intelligence, and no one suggests people aer just becoming better familiar with the questions in a standard IQ test. In the 1950s people taking an IQ test would see that kind of question for the first time, while in the 1990 everyone (in western countries) would have seen a book titled 'how to prepare for an IQ test' on his local bookstore.

People solve the questions faster because they already know the general task to be performed, and already know what solutions to expect. This knowledge developed gradually over time, as more and more people became exposed to the test, slowly shifting the average.

I don't know if this is original research, and I find it hard to believe as this explanation seems trivial to me. Has really no researcher suggested such an explanation? Could it be that people who publish in this field are so attached to the supposition that IQ tests measure an intrinsic generic property of people rather then measuring a single skill - to get high scores in IQ tests...

Cederal 10:29, 23 December 2006 (UTC)

Well, I believe this issue has been considered, not only regarding the Flynn effect, but in the general debate about the validity of I.Q. tests and the difficulty in keeping them valid as a population becomes more sophisticated. Presumably, tests have been continually reworked and restandardized in this attempt, and the psychometric community at least feels this has been addressed . . . and therefore the Flynn effect may not be a result of what you have suggested. —Preceding unsigned comment added by 68.83.48.84 (talk • contribs) 01:44, 26 December 2006

Morphic Resonance

Seems to me that the Flynn effect supports Rupert Sheldrake's ideas of morphic resonance. 192.139.140.243 05:19, 6 January 2007 (UTC)

split section

the psychometric properties of the flynn effect should be distinguished in discussions from the attempted explanations of the causes to the extent that that is possible. --W.R.N. 21:04, 11 February 2007 (UTC)

problem sentences

1. The "Abecedarian Project", an all-day program that provided various forms of environmental enrichment to children from infancy onward showed IQ gains that did not diminish over time
2. This explanation is troublesome for those who argue that IQ tests, and especially Raven's, measure a general intelligence factor accurately.

reasons:

1. this is disputed by spitz (sp?) and others
2. how common is this view -- who can it be attributed to? as stated, i imagine it must have been controversial b/c RPM is a constant subject of study. --W.R.N. 21:54, 11 February 2007 (UTC

Only citing from the source, Neisser.Ultramarine 22:07, 11 February 2007 (UTC)

Decline of IQ Scores in Germany, Austria, Norway and Switzlerland

Hey, I am a guy from Germany, who has a minor in psychology and writes for the German Misplaced Pages. In Germany that fact is much discussed, that we have seen a decline of the iq scores since the 90s. This has been proven by professor Dr. Urs Schallberger from the University of Zürich, Siegfried Lehrl from the University of Erlangen and Jon Martin Sundet from the University of Oslo. Here are some German links about this:

• German Link
• famours German newspaper on the decline in IQ scores

I think that should be added into the article. I would do that myself if i was able to speak english well enough.

Would you agreee with me, that this facts should be added? If yes, could you do me the favour and add them? Thanks! Patrick -- Cumtempore 09:02, 19 March 2007 (UTC)

edit: i just saw, that Norway has already been mentioned. So forget, what i said about Norway. Nevertheless Germany, Switzerland and Austria should be mentioned to my mind. -- Cumtempore 09:08, 19 March 2007 (UTC)

D € F model

"in direct contradiction of the Dickens and Flynn model which links the Flynn Effect to the cultural rather than the g component of IQ." Unsourced, and g is not entirely genetic.Ultramarine 02:02, 21 May 2007 (UTC)

Never implied it was entirely genetic. But it is entirely biological. It's possible to raise a person's IQ by 20 or 30 points through intellectual stimulation, but intellectual stimulation has been proven do to nothing for g, because g is 100% biological. My source is "The g factor: The Science of Mental ability" by Jensen. What this means for the article is that if the Flynn Effect is related to g then that means it must be caused by improvements in the biological environment like nutrition, but if it's not related to g, then it could be caused by either the biological environment or the cultural environment Secularrise 02:14, 21 May 2007 (UTC)

What do you mean by "entirely biological"? That is causes changes in the brain? Everything affecting IQ causes changes in the brain, including cultural factors such as stimulation. Jensen's claim in his book is dscussed and disputed by Flynn's and Dickens article who is published later than the book, so you cannot use it as a source to disprove the article.Ultramarine 02:19, 21 May 2007 (UTC)

By biological I mean non-psychological. According to Jensen, g can not be psychologically manipulated. Jensen agrees that g is not 100% genetic and can be influenced by the environment but only the biological environment. So identical twins who differ in g differ because of things like nutrition in the womb, nutrition in childhood, substance abuse, number of times they've hurt their head etc. But how often they are exposed to intellectual stimulation has NOTHING, ZERO, ZIP to do with their level of g. Do Flynn and Dickens dispute this? I though their paper was about IQ, not about g specifically. Secularrise 02:28, 21 May 2007 (UTC)

Still unclear, what is "non-psychological". Everthing affecting IQ changes the brain in some way and affects psychology. Dickens and Flynn disputes Jensen's claims in their article, it also mentions g.Ultramarine 02:33, 21 May 2007 (UTC)

What he means is that experiments like Head Start, the Milwaukee Project etc failed because by exposing kids to intellectual stimulation, all you're really doing is teaching them skills and knowledge. However intelligence is not knowledge. Intelligence is what you do when you don't know what to do (novel adaptive problem solving, thinking). To increase g (instead of just IQ) you must PHYSICALLY manipulate the brain (i.e. nutrition, health care) instead of psychologically manipulating the brain. Psychological manipulation can only increase knowledge which makes one artificially score high on a poorly designed IQ test, it can not increase true intelligence or g Secularrise 02:46, 21 May 2007 (UTC)

If you want to dispute their article, publish one yourself. Personal opinons are not allowed in Misplaced Pages. Again, cultural stimulation may PHYSICALLY change the brain, for example causing it to grow, just like physical stimulation can cause muscles to grow. Muscle size is not fixed by nutrition and health care.Ultramarine 02:54, 21 May 2007 (UTC)

You're assuming g is analogous to physical strength. It is probably more analogous to height which can not be increased through stimulation and is fixed by genes and nutrition. And I'm not really inserting my opinion so much as Jensen's conclusion that g can not be increased by cultural, educational, psychological stimulation. Hence if Dickens and Flynn are saying the Flynn Effect is caused by such stimulation, they have to show that it it's the non-g component of IQ that has increased. This is contradicted by the studies linking the Flynn Effect to g Secularrise 04:24, 21 May 2007 (UTC)

Just because Jensen writes one thing, it is not necessarily true. Dickeans and Flynn disputes several of Jensen's claims in their paper. It is not we should decide who is right.Ultramarine 04:28, 21 May 2007 (UTC)

Just to make one example. Flynn and Dickens argue that using the same methodology that Jensen's uses to show that the black-white gap is partly genetic, one can show that the differences in time is partly due to genetic factors. That is, using Jensen's methodology, the Flynn effect is substantially due genetic improvement, which is extremely unlikely.Ultramarine 04:37, 21 May 2007 (UTC)

He has a point, but one could use the same logic to argue that height differences between men and women are not genetic. After all, men today differ as much in height from men centuries ago, as men today differ in height from women today. Yet everyone seems to agree that men are genetically much taller than women. Secularrise 05:19, 21 May 2007 (UTC)

Dickens and Flynn see IQ as somewhat similar to muscle size. If you keep up training and stimulation, you can achieve a higher IQ than what genetics and early environment blessed you with. They argue that their model resolves all contradictions. If you want to dispute it, publish a paper.Ultramarine 05:51, 21 May 2007 (UTC)

They fail to differentiate between IQ and g which makes their theory meaningless. Everyone already knows that IQ can be increased by up to 30 points through educational intervention. It's whether g can be increased is the interesting question and one they fail to respond to. Secularrise 05:55, 21 May 2007 (UTC)

Again, publish a paper is disputing their findings. Misplaced Pages does not allow original research.Ultramarine 05:58, 21 May 2007 (UTC)

Also read Misplaced Pages:No original research.Ultramarine 06:00, 21 May 2007 (UTC)

It's not original research. It's Jensen's research showing that g can not be increased through stimulation. If you have a quote from them saying g can be increased through stimulation then add it, but until then, what's the problem? Secularrise 06:01, 21 May 2007 (UTC)

Something is not true just because Jensen has written it. Read the paper.Ultramarine 06:03, 21 May 2007 (UTC)

Which is somewhat technical. Here are less obscure explanations: .Ultramarine 06:20, 21 May 2007 (UTC)

Are there still objections to the the description given by me above? If so, please explain so we can discuss this. Otherwise I correct the text.Ultramarine 07:45, 23 July 2007 (UTC)

This is not a shouting contest, and, consequently, just because you wrote the latest comment doesn't mean that you're the winner. And just because some politically correct pair of psychologists tries to discredit Jensen's findings doesn't mean that Jensen's findings are false. 88.148.192.141 15:16, 17 August 2007 (UTC)

1) Who's shouting? 2) There are no "winners" on Misplaced Pages. 3) It's not "politically correct" it's good ol' fashioned "correct correct" until someone offers evidence otherwise 4) Unless you are a dualist, "intellectual stimulation" is biological. —Preceding unsigned comment added by 68.213.104.90 (talk) 15:12, 29 September 2008 (UTC)

Effects of Environmental Lead

Nevin (Environmental Research Section A 83, 1}22 (2000)) proposed that changes in childhood lead exposure may be connected to the Flynn effect. I propose that this should be referenced in the article. —Preceding unsigned comment added by 128.183.19.2 (talk • contribs) 16:14, 9 July 2007

Note to the person who wrote it. If you believe it is appropriate to add, why not do so? and please sign your comments by using four tildes, like this but without the spaces ~ ~ ~ ~

Skywriter 04:09, 24 July 2007 (UTC)

Broken link

With 10 initial references, this article is heavily dependent on the following article yet the link to the PDF is broken. Anyone have a new link?

1 a b c d e f g h i j Rising Scores on Intelligence Test Neisser, U. (1997). American Scientist, 85, 440-447.

Thanks.

Skywriter 04:09, 24 July 2007 (UTC)

The numbers in this article are meaningless.

There are numerous references to IQ scores in this article, both in the form of points and in the form of absolute numbers (such as Aristotle's hypothetical IQ.) However, without a standard deviation these numbers are meaningless. For example, a score of 135 on a standard deviation 15 test will get you into Mensa, but it is only above average on a standard deviation 30 test. Furthermore, references to children's IQ tests should remain separate from adult IQ tests. Children's IQ scores measure intelligence based on age group, where as adult IQ scores show intelligence based on the general population. Comparing the two scores is not only pointless, but misleading. As it currently stands, this article is unacceptably vague. It gives a good definition of what the Flynn Effect is, but anyone attempting to seriously understand the subject is going to be getting false information. If the original authors could track down their sources and put the standard deviation numbers into the article, it can be repaired, otherwise this whole page may have to be rewritten.

Snickeringshadow 07:30, 8 August 2007 (UTC)

Another viewpoint on this. The following statement is ridiculous and shows why people who don't understand math shouldn't write about it:

"However Arthur Jensen warns that extrapolating leads to results such as an IQ of -1000 for Aristotle (even assuming he would have scored 200 in his day)"

IQ is measured in terms of a normal distribution, which means that if you have an increase of 3 points in each of two decades, you have to do some actual math to find out what the effect is for the combined twenty year period. Guessing that it would be 3+3 = 6 is hopelessly naive.

The point itself, while poorly expressed, has some merit. If one assumes that this is culturally influenced, then that would imply that the effect should have been visible during the greek and roman empires, should have reversed going into the dark ages, and should have restarted during the renaissance. We should be asking for a lot of extra data if we want to extrapolate through this period.

Excess nutrition and the brain

User:MoritzB seems to confuse the effects of excess nutrition vs normal nutrition compared to normal nutrition vs malnutrition. It has been demonstrated that Blacks in the USA tend to cluster in the lower classes, where malnutrition is known to be prevalent. A study which demonstrates that excess nutrition doesn't affect the brain isn't relevant to the demonstrated effects of a a proper nutrition (vs malnutrition) on brain development in children. Therefore, I have removed the material as it isn't relevant and is in fact misleading.--Ramdrake 23:16, 1 September 2007 (UTC)

You have absolutely no idea what you are talking about. If you can paraphrase W.D. Hamilton's words better than I, please do but otherwise revert back to my version.

W.D. Hamilton writes: In the chapter he devotes to this paradox, Lynn concludes, I think probably correctly, that the largest factor in the mass rise in intelligence has been worldwide improvement in nutrition. In essence this is the very same factor as has made possible the parallel rapid rise in human stature, as also, in the background, the great growth in world population. It is implied that undernourished humans from foetal life onwards put their meagre resources into `bodily' systems (in which I would include the immune system) before they put it into the `modern luxury' of their line ± the enlarged neocortex of the brain. This is an idea I will come back to; for the present please just note it as making passable evolutionary sense. But such offsetting by nutrition, Lynn notes, has to have a limit: `Thes eenvironmental improvements are bound to be subject to diminishing returns. When their impact is exhausted, and if dysgenic fertility continues, phenotypic intelligence will begin to decline' (p. 112)". MoritzB 23:34, 1 September 2007 (UTC)

Wow. Hamilton speaking about Lynn speaking about the Flynn effect, hypothesizing that the Flynn effect might actually have a ceiling at one point. This is pure speculation, not backed by any data, and is fringe to boot. I would say it is certifiably unencyclopaedic. Besides, this extract supports in no way the sentence you were trying to put in.--Ramdrake 00:23, 2 September 2007 (UTC)

Flynn shows in his most recent book that nutrition can only possibly account for pre-1950's gains in post-industrial countries, and even then there is evidence against it being the main factor. Furthermore, Flynn falsifies the idea that intelligence gains since the 1950's in post-industrial countries are accountable to nutrition. I suggest you read his book before you claim to understand the complexities of the still uncompletely understood Flynn effect.--156.56.153.70 18:04, 10 October 2007 (UTC)

The opposite

My father, studying psychology in the 1920s, was taught that the average IQ was declining by a point per generation because low-IQ people were having more children than high-IQ people. That sounds like an idea from eugenics, which had a large following at the time. If that viewpoint can be documented, it might be worth mentioning in the intro. Dynzmoar (talk) 20:27, 19 December 2007 (UTC)

I see your point, but dysgenics is really only peripheral to the Flynn Effect; IQ scores have been rising, regardless of what may be going on at the genetic level. Dysgenics is mentioned briefly in the body of the article, and honestly I think that's where it should stay.

(By the way, I'll add that I'm impressed by this article. I can see some room for expansion, but all the main points are covered. All in all, I'd like to congratulate the contributors on a job well done.) Harkenbane (talk) 21:29, 8 March 2008 (UTC)

Over in England as well?

Telegraph, "British teenagers have lower IQs than their counterparts did 30 years ago":

"Tests carried out in 1980 and again in 2008 show that the IQ score of an average 14-year-old dropped by more than two points over the period...The trend marks an abrupt reversal of the so-called "Flynn effect" which has seen IQ scores rise year on year, among all age groups, in most industrialised countries throughout the past century.
Professor James Flynn, of the University of Otago in New Zealand, the discoverer of the Flynn effect and the author of the latest study, believes the abnormal drop in British teenage IQ could be due to youth culture having "stagnated" or even dumbed down."

Doesn't seem to be covered in the 'end of progression' section. --Gwern (contribs) 16:21 22 February 2009 (GMT)

I added it in, as well as the BNP's implication that immigration is to blame. Esn (talk) 06:34, 29 June 2009 (UTC)

Over in the U.S.?

The WAIS-IV is out now, so have there been any reports that the Flynn Effect has ended in the U.S.? This would be a good thing to add to the article. Flynneffects (talk) 08:08, 8 April 2009 (UTC)

Anyone know what this means? Is it OR??

But if you follow Dickens & Neisser values, apply them a bank rate formula, according to Environmental enrichment (neural) and by using the cycle's theory of Oswald Spengler (presented by A. E. van Vogt), you can easily create a curve of evolution. Here is one projection who integrates the possible ceiling incoming and then avoiding the Jensen prediction

1Z (talk) 13:17, 2 September 2009 (UTC)

The Flynn Effect proves that intelligence can be increased.........

I am a 3rd year psych student at Northern Illinois University, and I have long been interested in the structure of IQ tests. I know that has become fairly clear, and widely acknowledged in recent years, that conventional IQ tests, such as the WAIS, Woodcock Johnson, Standford Binet ect., are disproportionately loaded on the crystallized factor (Gc). Whereas Gc taxes short term memory capacity and retrieval from long term memory, Gf (fluid intelligence) taxes both STM, LTM, and the suite of skills that make up 'Executive Functions' (EF). EF, in the most basic description, allows for the 'mental juggling', of information in STM and LTM. The classes of problems that tax Gc and Gf are considerably different, and the American education system, has failed to acknowledge this for a very long time. But perhaps for good reason; while the former factor is relatively constant throughout a lifespan, there is an abundant amount of data to support that the latter, is quite trainable (The well known discrepancy between autistic Gf/Gc, fluid intelligence increases through n-back training (see Jaeggi et al and more under review), Flynn effect, impairments of Gf in patients with mental disorders (Blair), neuro-imaging revealed, age-related, changes of the pre-frontal cortex, child prodigies, domain creativity, the effect of schooling on fluid intelligence). So why the failure to adopt a model of dynamic intelligence? Because A) The West has longed leaned towards the principles of Eugenics and B) America has become flooded with a range of minorities, who's high emphasis on education and intellectualism may potentially be revealed (at least through some frame of time), on highly Gf loaded tests.

Z79 NoVEMBER 9 —Preceding unsigned comment added by 24.1.114.97 (talk) 02:47, 10 November 2009 (UTC)

Organization

The proposed-explanations section needs splitting up and sorting of factoids by the hypothesis they support or undermine. http://www.indiana.edu/~intell/flynneffect.shtml#what is an example of how there should be multiple subsections. As it is, the section is a wall of text which doesn't even offer an itemized list or summary. (Also, it would be good if the French diagram were translated into English.) --Gwern (contribs) 03:02 1 April 2010 (GMT)

Intelligence Citations Bibliography for Articles Related to IQ Testing

You may find it helpful while reading or editing articles to look at a bibliography of Intelligence Citations, posted for the use of all Wikipedians who have occasion to edit articles on human intelligence and related issues. I happen to have circulating access to a huge academic research library at a university with an active research program in these issues (and to another library that is one of the ten largest public library systems in the United States) and have been researching these issues since 1989. You are welcome to use these citations for your own research. You can help other Wikipedians by suggesting new sources through comments on that page. It will be extremely helpful for articles on human intelligence to edit them according to the Misplaced Pages standards for reliable sources for medicine-related articles, as it is important to get these issues as well verified as possible. -- WeijiBaikeBianji (talk) 19:31, 30 June 2010 (UTC)

I strongly encourage fellow Wikipedians to read the current professional literature on IQ testing, which has been prompted to pursue a number of previously neglected issues by James R. Flynn's path-breaking papers. If you know of current, reliable secondary sources that comment on Flynn's findings, feel free to share them with other Wikipedians on the talk page of the source list mentioned immediately above. -- WeijiBaikeBianji (talk) 04:10, 8 September 2010 (UTC)

Useful links to journal references on this topic

I just found, via a Google search, a quite interesting list of references Flynn Effect Reference Archive that will help guide Wikipedians to what are mostly primary sources on the Flynn effect. (Some of these references could be the basis for revising the article, because they are reliable secondary sources for the facts that they assert, and most of these references will be useful background reading for editors of this article.) Enjoy. -- WeijiBaikeBianji (talk) 01:40, 16 August 2010 (UTC)

Possible narrowing of US racial gap

The article currently contains the following text and in image: "Dickens and Flynn write in their 2006 paper Black Americans reduce the racial IQ gap: Evidence from standardization samples that blacks have gained five or six IQ points compared to non-Hispanic whites between 1972 and 2002. Gains have been fairly uniform across the entire range of black cognitive ability. J. Philippe Rushton and Arthur R. Jensen have disputed Dickens's and Flynn's findings, calculating a mean gain for Blacks of zero to 3.44 IQ points, and questioned the exclusion of four independent tests that showed low or negative IQ gains. However, in the very same 2006 study that was criticized by Rushton and Jensen, Flynn and Dickens give explicit reasons for why four tests were excluded. Rushton and Jensen include in test such as the AFQT which is not strictly an IQ tests and their inclusion of Herrnstein and Murray's AFQT data was criticized by Flynn and Dickens. Rushton and Jensen derive the figure of a 3.44 IQ point gain by adding data from four excludes tests to Table A1 while Flynn and Dickens' figure of a 5.5 IQ gain for black Americans was derived from Figure 3 in the study."

1. This is certainly not the final word on this. There are much more that can be said and cited about this.

2. This subject is already discussed here: http://en.wikipedia.org/Race_and_intelligence#Score_convergence

3 If the US scores are converging then this may or may not be related to what causes the Flynn effect in other nations.

As such I see no need for a duplicate discussion of the subject in this article. The material should instead be replaced with a brief mention of the controversy together with the link above to the race and intelligence article where possible US score convergence is properly discussed.Miradre (talk) 14:37, 12 October 2010 (UTC)

removed Teasdale/Owen

I spent the afternoon reviewing this paper. The major conclusions from the paper did not match the copy in the article, which selectively presented possible explanations for the data which were only speculated in the paper. This appears to be a classic example of some of the difficulties with using primary sources. aprock (talk) 01:38, 13 October 2010 (UTC)

A peer-reviewed article is a reliable source certainly allowed in Misplaced Pages. If something was missing from the description then you should complement it and not remove it completely. If you do not do so yourself I will add back the article with some more details.Miradre (talk) 05:54, 13 October 2010 (UTC)

Proposed new text which include both the possible explanations proposed by the authors (no, the authors do not favor either one and the educational changes one has already been mentioned in the article in connection with the 2005 study but lets repeat it): "Teasdale and Owen (2007), in a study on young adult males in Denmark, found that there was a modest increase between 1988 and 1998, but a modest decrease between 1998 and 2003/2004. The difference was approximately 1.5 IQ points in both cases. A possible contributing factor to the recent decline may be changes in the Danish educational system. Another may the rising proportion of immigrants or their immediate descendants in Denmark. This is supported by data on Danish draftees where first or second generation immigrants with Danish nationality score below average. They also state that since the Flynn effect may have ended in at least a few developed nations, this may possibly allow the national differences in IQ scores (see IQ and Global Inequality) to diminish if the Flynn effects continues in nations with lower average national IQs." Miradre (talk) 07:09, 13 October 2010 (UTC)

The primary conclusion of the paper is that the scores in Denmark did in fact drop marginally over 1998-2004 period. All of the suggested possible explanations are not a part of the conclusion. Please see for further discussion of what sort of sources are preferred. aprock (talk) 07:17, 13 October 2010 (UTC)

The two proposed explanations are in the final discussion (sometimes called conclusion in other studies). Peer-reviewed academic sources are the highest sort of source available. Certainly not disallowed.Miradre (talk) 07:21, 13 October 2010 (UTC)

I quote from WP:RS "Material such as an article or research paper that has been vetted by the scholarly community is regarded as reliable."Miradre (talk) 07:23, 13 October 2010 (UTC)

There is much more than just being "peer-reviewed" that establishes the reliability of a source. Aprock is especially careful about sourcing issues, and I'm sure his editorial actions here were well warranted by Misplaced Pages policy. He has read the article carefully. An important issue here is proper use of primary, secondary, and tertiary sources. We have to be especially careful about sourcing issues in all articles related to the Arbitration Committee Case, which includes a reminder about source policy in the active sanctions adopted in the case decision. -- WeijiBaikeBianji (talk) 12:23, 13 October 2010 (UTC)

You have presented no reason for why the peer-reviewed article is incorrect. Regarding Misplaced Pages:NOR lets quote it: "In general, the most reliable sources are peer-reviewed journals and books published by university presses". As such I will add back the article unless a concrete reason is given for why this peer-reviewed scientific article is incorrect.Miradre (talk) 13:18, 13 October 2010 (UTC)

@Miradre. Yes, there are lots of things in the primary source. Only one thing is the major conclusion, the other stuff is not the primary topic of the source. Unless there is a reason to think that this study is notable, I see no reason to include it. aprock (talk) 14:39, 13 October 2010 (UTC)

Where is the policy forbidding citing specific parts of peer-reviewed studies? The statements regarding what may be behind the decline are presented in the two final paragraphs of the paper so they were in no way peripheral.Miradre (talk) 14:53, 13 October 2010 (UTC)

1. Cite error: The named reference reversal was invoked but never defined (see the help page).

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