Is 'IQ' testing an accurate means of testing?

Lots of interesting statistics and information posted here and lots of disagreement. I find myself confused, perhaps because I overlooked it while reading all the posts, but generally when discussing a particular idea everyone needs to be talking about the same thing. Could either Mlw or Deleet give me a definition of what IQ (intelligence) is.

Note: If you can't give a clear definition of what intelligence is, can you explain to me the purpose of all these results, i.e. are they used to help better define what IQ could be and therefore could you give science's best guess of what they currently think what the definition of IQ is.

I have no idea what was said over the last 7 pages. I don't really have time to read it (right now) so I apologise if any of this is a rehash of things other people said.

• IQ is calculated by how well you do on the IQ testing compared to everyone else in your general age range.
  
• IQ testing tends to be more accurate after puberty.
  
• The IQ rating of a person is generalised.
  
• People who have test anxiety or other problems that make test taking difficult to them generally do not get an IQ score that accurately represents their intelligence.
  
• Most modern IQ tests recognise multiple areas of intelligence, many of them as high as 7 with some psychologists recommending 9 areas (the Cattell-Horn-Carroll theory and IQ tests designed by this theory recognise 10 areas).
  
• On an individual basis, IQ tests can potentially be very inaccurate, however in the broad view, IQ testing is statistically fairly accurate.
  
• Just because somebody has an extremely high IQ does not mean that they are necessarily able to do anything and everything.

In general, IQ testing works, but I think it could be made a LOT better.

Intelligence to me is the totality of all the abilities of the mind together. For example, a high musical intelligence would be when a person has the ability to learn music extremely quickly, more easily understand it, can more accurately use it or apply it or knowledge of it, and can think about it in the extremes of the abstract possibly even being able to come up with new theories on music or to make music that still works even though it deviates from the "rules" of composition.

I personally think that a true IQ should measure a person's ability to think and use their mind. How easy is it to understand abstract concepts? How easy is it to abstract a concrete concept? How quickly does the person learn? How well does the person remember what has been learned? How well can a person apply knowledge? Howe easily can the person comprehend things in general and so on.

"Abstract concepts" are not "understandable". And if they are, then they are not abstract enough. Here-in lies the problem with assessing "intelligence". The mere median of humanity decides that value should be placed upon thoughts and thinkers who are equipped to serve the (median level) of the collective. So they will identify superstar idiots to lead them by this IQ test. But those who possess great will and originality that is not immediately and animalistically aligned with "human progress" cannot and will not be bothered with their test taking. And, ironically, THEY are the ones that indeed end up improving humanity...not the IQ fraternity. Its okay though, science and service and social and psychological nonsense cannot stifle individual human originality. So the anti-evolution is doing exactly what it does, in spite of everything.

It seems that the controversial issue here is the definition you are using for "intelligence". If you are looking at specific skills such as mathematics then there are "scientific" measurement tests directed at that specific skill. However, "intelligence" has such a wide range of possible definitions that it seems silly to assume that a single "quotient" measurement can reflect the huge panorama that is " intelligence". Finally, all that matters is that the individual flourishes with and maximises those skills that he/she has - regardless of whether they are measurable as a "science". Who cares?

Finally, all that matters is that the individual flourishes with and maximises those skills that he/she has - regardless of whether they are measurable as a "science". Who cares?

This goes back to an intelligent person being one who knows himself. The better he knows himself the better that he can maximise those skills he has.

The question that asks wether IQ test is good enough to measure indiduals mental stature is a bit amiguous. Because the IQ that we want to meaure must be predefind and the scales must be set accordingly. There are some intelligence groups which do trade off each other and we can't find them together. Hence if we narrow the IQ type we want to test it is highly likely to get accurate data. On the contrary if we increase the number of IQ groups to be tested, the error terms will grow at exponetial scale.

One aspect of the question has not been discussed here at any length—the construction of the general intelligence factor or g factor through factor analysis. Since it bears on the definition of intelligence itself, it may be worth the time. It's technical, but interesting.

In everyday life intelligence is not a quality observed directly like height or weight, instead it is a quality inferred from success in school, work, and problem solving. People who excel at lots of different mental activities are deemed intelligent.

Since a direct controlled measurement is desirable for scientific studies and practical uses, intelligence testing was developed over the last century. A good intelligence test should be independent of cultural factors and education—conditions not easily met. Intelligence scores from different tests are positively correlated among themselves and positively correlated with success in school and work, that is, they all generally vary in the same direction. They are not perfectly correlated, just as height and weight are not perfectly correlated. Tall people overall weigh more than short people, but there are tall and skinny people and short heavy people.

How are scores from different intelligence tests to be compared and evaluated? If they are all measuring the same ability, they ought to be highly correlated with each other and over time for the same individual. If not, are they actually measuring intelligence? This is the kind of question that factor analysis is designed to help resolve. You might think that simply averaging the scores of all the different intelligence tests would be a good way to find a better measure of intelligence than any one of them could offer. That is not always a bad idea, but mathematically there is a better one—factor analysis.

The mathematics of factor analysis is linear algebra, not the most advanced mathematics by any means, but too much to explain here. To keep it simple, suppose you have two intelligence tests that generally agree, T₁ and T₂. That is, they do not exactly agree, but they correlate. The idea is to find out what it is they measure in common and use that constructed measure or factor to serve as a better proxy for intelligence than either would be by itself. If that factor is called F, then the result of the analysis would be to find F along with λ₁, λ₂, ε₁,ε₂
so that we have

T₁ = λ₁F + ε₁ and T₂ = λ₂F + ε₂.

In other words at the end of the analysis you can see what the unobserved factor F contributes to T₁ and T₂ and in effect the two original variables are determined by one constructed variable. The general solution to this problem is not unique. The idea goes back to Charles Spearman in a paper published in 1904 and it was developed specifically to deal with the question of intelligence. The mathematical technique has since been used in many areas, but especially in the social and psychological sciences where concepts are hard to measure directly.

Those who use this technique in the analysis of intelligence testing call the constructed factor g for general intelligence factor. It cannot be measured directly and its distribution over the population cannot be known, but might be expected to be a normal distribution. The real question then that underlies the discussion here is whether g—however defined— in any sense measures something real, a latent and unobserved variable that is an accurate numerical reflection of what we mean by intelligence or whether it is simply an artificial construct with little meaning.

A major controversy over this question arose with the publication of Stephen Jay Gould's book The Mismeasure of Man in which he discussed the use of factor analysis in estimating intelligence and argued against it. Gould's book was popular and won awards, but it also drew vehement criticism from those in the field who were using factor analysis. A similar controversy erupted again after publication of The Bell Curve in 1994, but not specifically over the use of factor analysis.

The g factor remains the essential item in arguments that intelligence is hereditary and varies among ethnic groups.

One aspect of the question has not been discussed here at any length—the construction of the general intelligence factor or g factor through factor analysis. Since it bears on the definition of intelligence itself, it may be worth the time. It's technical, but interesting.....

A major controversy over this question arose with the publication of Stephen Jay Gould's book The Mismeasure of Man in which he discussed the use of factor analysis in estimating intelligence and argued against it. Gould's book was popular and won awards, but it also drew vehement criticism from those in the field who were using factor analysis. A similar controversy erupted again after publication of The Bell Curve in 1994, but not specifically over the use of factor analysis.

The g factor remains the essential item in arguments that intelligence is hereditary and varies among ethnic groups.

Thanks a lot for this Prismatic. I'd quite forgotten the Gould controversy till you mentioned it.

I'm interested in the philosophical area where empirical study, concept origin and overall hypothesis meet. My gut reaction is to agree with Gould that psychologists tend to reify g, as if identifying some abstraction that can be related 'eventually' to some physiological traits or factors. I'm not clear how you can ever eliminate through factor analysis the possibility that g is just the ability to pass the sorts of tests that are devised by the sorts of psychologists who like testing. 'Creativity', for instance, or musical aptitude, seem to me just as valuable for human culture but don't get a look-in as factors adduced by intelligence testing (as I understand it). But I gather that most people feel Gould got it wrong.

A parallel conceptual problem would be in the idea of 'addiction'. There's a lot of loose talk in academic circles as if addiction to some activity or substance were an identified and identifiable physical trait in a human being, and/or something identified in the substance. Some career-sized castles have been built on this sand. 'Addiction' (like 'intelligence') is an idea we want to have, for social and political reasons. It clearly lies somewhere beyond 'habit' and even 'self-compulsion', but quite what it describes, and how it relates to human and substance biology, are tricky things to comprehend.

Thanks a lot for this Prismatic. I'd quite forgotten the Gould controversy till you mentioned it.

I'm interested in the philosophical area where empirical study, concept origin and overall hypothesis meet. My gut reaction is to agree with Gould that psychologists tend to reify g, as if identifying some abstraction that can be related 'eventually' to some physiological traits or factors. I'm not clear how you can ever eliminate through factor analysis the possibility that g is just the ability to pass the sorts of tests that are devised by the sorts of psychologists who like testing. 'Creativity', for instance, or musical aptitude, seem to me just as valuable for human culture but don't get a look-in as factors adduced by intelligence testing (as I understand it). But I gather that most people feel Gould got it wrong.

A parallel conceptual problem would be in the idea of 'addiction'. There's a lot of loose talk in academic circles as if addiction to some activity or substance were an identified and identifiable physical trait in a human being, and/or something identified in the substance. Some career-sized castles have been built on this sand. 'Addiction' (like 'intelligence') is an idea we want to have, for social and political reasons. It clearly lies somewhere beyond 'habit' and even 'self-compulsion', but quite what it describes, and how it relates to human and substance biology, are tricky things to comprehend.

Gould's book is a great pleasure to read, but it received such violent criticism of its honesty and accuracy that it makes you shy away from saying he's unquestionably right. Gould does not quite make the argument one wants to see. You could I think devise an example of well correlated measures that are totally unrelated and mathematically produce a factor correlated with them all. It would underline Gould's point that the validity of a factor analysis must come from outside the analysis itself, from the content of the subject, not the statistical distribution of data.

...From the other posts and above, I see a lot of arrogance, bigotry, condescension, dogmatism, pedanticism and a hoard of negative human values here which is not healthy for discussion in any forum, and it is all due to some crazy ego and ignorance.

Altogether, a desperate desire for determinism: I don't want anything to change; please, God, let it be like it always was.

...concepts, 'value theory', axiology, ethics, and other philosophical aspects surrounding the issue of the methods and accuracy of IQ testing.

I took some IQ [I believe it was called the Stanford-Wexler test; no longer Stanford-Binet (unless you're super-determinist) or maybe a variation on it] test 20+ yr ago. This wasn't to test my intell. for a grad. program or a better job or for planning U.S. foreign policy in the Balkans: it was to bring the results of something (something!; anything!) to court while I was seeking visitation w/ my kids. Believe me, there was nothing so hi-falutin' as axiology, ethics, & philosophical aspects. @The same time, I began to think how bizarre it was that whereas I needed no test to father kids, I now needed positive test results to show I was worthy of even seeing them. America began to seem like a very perverse & perverted place to me.

Then I wondered how well that test tested my intell. or my capacity for empathy or my parenting skills (was there a test for those? would I pass?), since I slogged thru the ordeal completely imagining how results---any results---would be taken by some crusty judge, leaning into retirement. I was very appreciative of the report the psychologist filed w/ the court, but I knew that test showed nothing but what a miserable, depressed, angry, middle-age American slug was doing against his will.

Thanks, but it is slightly different from intuition. You have a problem, but because you do not know what you are looking for, is like having the problem without any information. Without information you cannot solve the problem. I suspect that this is more a question of perseverance as you go about searching for the information. And I suspect that IQ tests do not measure that, or do they?

This is exactly intuition. Intuition is "perception via the unconscious". When we lack information, we can have recourse to intuition. Carl Jung placed it foremost among the psychic functions. People without intuition are virtually blind. /Mats

Intuition seems to me realizing that if I place a hand over something hot, it will burn me. I solve that problem without having to go through the conscious process of trying to work out why it happens.

Why are we here? We cannot accurately measure what we cannot accurately define. IO scores assume what they purport to measure. IQ score does not equal the probability of being correct. After all, I am always right. Sorry for not reading all the responses if this is (and should be) redundent!!

My conclusion: there are a lot more of intelligent people than IQ test is designed to recognize. I do not understand, my IQ is 210 and my daughter's is 205, yet we are not Einstines, do not work in science, did not win Noble prize, etc. We are intelligent, even I say she's more so, only has less experience with life. What is so exceptional about such IQ's? I do not see myself as an exceptional person. This also raises red flag about IQ tests meaning.

My entire question here is: Is 'IQ' testing an accurate means of testing a persons overall intellectual ablility? For example, Eienstin was considered to be a 'genuis' due to his comprehension of higher mathematics. Yet, it has been reported that he was observed to have difficulty tieing his own shoelaces, and counting his own pocket change. Does this make someone who does not have these problems overall less intellectual? Although I do not now remember what the test was called, when I enlisted for military service, I was given a test that showed I had a 'GCT' score of 111, with I believe a 'genuis' level starting at 120. AT the time, it showed that I was 'good' at math, and was mechanically inclined. Subquently, I recieved training for, and became an aircraft mechanic. Does this necessarily mean that I am overall less intellectual than someone else? Subsequently, it is my belief that a persons overall intellectual ability should not be assessed solely throught 'IQ' tests, but that other testing should be considered also, and then collated, giving the persons overall intellect. Opinions?

The IQ test is a very consistent and reliable way of testing IQ. In fact there is no better way to test this. It is 100% reliable. It is a means by which the dominant ideology allows itself the pleasure of setting itself above all other modes of thinking. It is racially, demographically and culturally insensitive and privileges the same psychological types that invented and promote the test.

It does not accurately quantify intelligence as any really intelligent person will tell you that such a complex concept is not one that can be so easily quantified.

-- Updated Mon Jun 25, 2012 2:56 am to add the following --

My conclusion: there are a lot more of intelligent people than IQ test is designed to recognize. I do not understand, my IQ is 210 and my daughter's is 205, yet we are not Einstines, do not work in science, did not win Noble prize, etc. We are intelligent, even I say she's more so, only has less experience with life. What is so exceptional about such IQ's? I do not see myself as an exceptional person. This also raises red flag about IQ tests meaning.

IQ = the ability to pass an IQ test.

The IQ test is a very consistent and reliable way of testing IQ. ....... IQ = the ability to pass an IQ test.

100% agree