IQ Isn't Set In Stone, Suggests Study That Finds Big Jumps, Dips In Teens
npr.org
npr.org
I used to hate standardized tests (and still somewhat do in principle) but when you can show that a test score correlates to performance it does make sense to assist in making decision when there are very large sets of data to process (like college applications). It turns out that SATs do correlate somewhat to freshman year performance. It doesn't really matter if it's for the right reason, if you have thousands of similar applicants it makes sense to use that data point if there are no other options. This is the logic of machine learning too: I don't really care why 2 variables correlate, if they do it can help me make decisions.
The issue for me is that I have yet to see anything interesting about what IQ really correlates to. Pretending it is a test that measures intelligence is completely asinine if you take 2 minutes to think about what that claim means.
What happens is that people would rather put faith in the correlation between IQ scores and intelligence, rather than nothing at all. It's annoying as hell as IMHO a +/- 15 points doesn't mean anything, but that doesn't stop people making decisions based on that. On the other hand you can clearly say that somebody with an IQ of 240 is gifted or that somebody with an IQ of 60 is challenged.
The problem with SAT scores is that people doing well on it are the people fresh out of high-school. You cannot give a SAT test to somebody that's been 10 years out of high-school or to a 10 year old.
Everything else that calls itself an IQ test is really a form of pop science quiz and of course has flaws. Any test that you're supposed to administer yourself is not the IQ test - that's the easiest first step.
Let's say I have a Teakettle test which assigns a score to the temperature of the water in a teakettle based on only qualitative properties of a teakettle (is it whistling, is it rumbling, does touching it cause pain?). This test is probably good at assessing the extreme cases (water is 212 F, water is around 70F) but I'd guess it's a poor predictor of temperature. Now if you gave me a thermometer I could see how correct my test was.
The problem is we don't have a thermometer for intelligence (that I know of) and more important I don't know if there is any consensus that 'intelligence' can even be assigned a quantitative value the same way the vibration of molecules can.
Now maybe the IQ test, like the Teakettle test, is a good summation of qualitative properties. Now you can compare this quantitative value to others to show a useful correlation. The Teakettle test may be a really great way to predict time to tea-time. An IQ score can only be useful if it shows a strong correlation to other, quantitative things (SAT score, salary, life expectancy, number of hairs in eyebrows)
To say that a real IQ test is a decent measure of intelligence seems to be at best a tautology.
Intelligence is not a property like physical attributes. It is fuzzy and has a lot of aspects. Some forms of intelligence aren't tested with the IQ test (unless somehow done recently), the primary one that comes to mind is social nous.
The psychology of intelligence is a complex, varied, and interesting field, and those who naysay "you can't study / define / measure intelligence!" are submitting to pop science just like "take this pop IQ quiz!". I've lost track of it over the years, but there are reams of research into intelligence, what it is, how it's defined, how tests do or don't reflect intelligence.
The IQ test covers a lot of different aspects of intelligence - it gives a fairly comprehensive representation of many aspects, and hence why it's a decent measure of intelligence. It's not a cut-and-dried thermometer measure, yes - but this is because psychology never works that way, something that engineers have trouble getting their heads around. Nothing in psychology is concrete, and if you're going to dismiss based on not being 100% precise, well, then psychology can't exist, nor can any of the fields based from it (like sociology, criminology, so on and so forth)
Don't the shortened IQ tests correlate pretty strongly with the longer ones? When I read psychology papers, even ones dealing with children, they pretty frequently use speeded or abbreviated ones without apparent qualms.
I did a partial IQ test when I was studying intelligence. I was on track for getting around 140 according to the conductor of the test. But I can't say my IQ is 140 because I may have fared worse (or better!) on other parts of the test (for example, we didn't even touch on the verbal tests).
What kind of odds would you give me that a group of people in the 10th percentile will have a higher average income than a group of people from the 90th percentile? If all IQ measures is your ability to take an IQ test, I think you'd be pretty confident that the bottom 10% will perform about as well as the top 10%. So, would you up up for 1:1 odds on that?
If you're willing to bet consistently with your beliefs, please get in touch; my email address is in my profile.
Unless the top 10% has some systemic advantage at taking IQ tests. Type words into a search engine for further inquiries in this area.
Obviously, it's possible to imagine a world in which IQ is not largely heritable, and in which rich people pay lots of money to game their kids' IQ numbers, and then the kids somehow use these IQ test numbers to get better jobs (even though IQ testing from employers is basically illegal).
But we can adjust for that. I'd be happy to do the same bet controlling for parental socio-economic status.
You don't need to imagine that world, we live in it. Kids who go to private schools with SAT prep classes and practice the test dozens of times are at a several hundred point advantage to kids who don't. This gets them into better colleges which gets them better jobs and gets them better income.
As for what it actually measures (as opposed to what it trys to measure), opinions differ...
http://en.wikipedia.org/wiki/SAT#Correlations_with_IQ
"Frey and Detterman (2003) analyzed the correlation of SAT scores with intelligence test scores.[20] They found SAT scores to be highly correlated with general mental ability, or g (r=.82 in their sample). The correlation between SAT scores and scores on the Raven's Advanced Progressive Matrices was .483 (.72 corrected for restricted range). They concluded that the SAT is primarily a test of g. Beaujean and colleagues (2006) have reached similar conclusions.[21]"
"Certain high IQ societies, like Mensa, the Prometheus Society and the Triple Nine Society, use scores from certain years as one of their admission tests. For instance, the Triple Nine Society accepts scores of 1450 on tests taken before April 1995, and scores of at least 1520 on tests taken between April 1995 and February 2005."
The name originally stood for "Scholastic Aptitude Test".[35] But in 1990, because of uncertainty about the SAT's ability to function as an intelligence test, the name was changed to Scholastic Assessment Test. http://en.wikipedia.org/wiki/SAT#History
At one point, the administration at CMU came to him and asked if he could figure out what was the best predictor of students finishing college. (Or it might have been just freshmen year. It's been a few years since that course.) He had access to all of CMU's data on students. The result: SAT scores.
Whether or not the SAT itself is a predictor of actual intelligence is besides the point.
On the other hand GPA's over 3 depend a lot on how hard your classes are, how heavy the work load, if you have a full/part time job which are less dependent on the student's innate qualities.
Of course SAT scores won't be predictive in that case. You'd want to look at SAT scores controlling for other admissions factors, which is basically SAT scores controlling for every variable admissions cares about, which of course means that no variable in particular has predictive power.
But if you want to see how strongly SAT scores correlate with academic performance, the way to do it would be to take some students who belong at, e.g., ASU, and somehow sneak them into Harvard.
Let's say you win this bet (which I wouldn't take since I never argued that was the case in the first place), all you have shown is that the ability to answer questions on an IQ test has a strong correlation with income. How does this have anything to do with intelligence, which the test claims to measure? If you where to say that "well this means that intelligence is strongly correlated with income" this is tautological since the IQ test is your only way to measure intelligence in the first place.
My assumption that IQ scores probably don't correlate that strongly to many things is based on the observation that we don't use it that much. If you look more thoroughly there are, as expected, obviously correlations between IQ and many things, but how strong those correlations are and the variance make many of them interesting but not fantastically useful.
Correlating with the extremes is not that interesting, now if you where to show that the is a strong correlation between IQ test percentile and income percentile across the board that would be interesting. If you're really interested there has been research into the correlation between IQ and Income and it's about 0.4-0.5 [1]
1. http://en.wikipedia.org/wiki/Intelligence_quotient#Income
This is a completely random statement. You could just as easily say that an analog scale doesn't measure weight, it measures how much a spring compresses when an object is placed on top of it. Since the spring is different every time, even the same scale is not going to be the same every day.
Measuring something and what it correlates with is exactly the same thing, and the distinction you are making is absurd pedantry.
I don't really have any strong opinion about your actual stances.
In an IQ test we are merely counting a set of qualitative properties (answered question n correctly). There is no underlying model that we are using to determine "intelligence", there is nothing quantitative about the IQ test other than counting the correct answers. We don't even have a quantitative model of intelligence at all, so there is simply no way to measure it. It is not pedantry to say that what an IQ test does is merely measure answered questions and not intelligence. If there where a.) a quantitative model of intelligence, and b.) a formula mapping this to IQ tests then, yes we could say we were measuring intelligence in the same way an analog scale measures weight.
I get your point, but I think it is still not quite a cut and dry as you are making it. The issue is not that intelligence is something quantifiable for which they haven't been able to map IQ on to; intelligence is just an ill-defined concept. Absolutely nothing can possibly measure or map onto intelligence because there just is no real definition of the word.
Saying that IQ measures intelligence is the same as saying that answering questions on a standardized test requires intelligence, which seems like a perfectly reasonable and valid definition to me.
Would you bring up this argument someone said "He solved that math problem that has been open for hundreds of years, he is intelligent". Would you jump in and say "actually, solving math problems isn't necessarily a measure of intelligence, which is what you are implying".
All that solving famous unsolved math proofs shows is that you are better at solving math proofs that a bunch of other people who try to solve math proofs, what does that have to do with intelligence!
What you cannot do, despite any amount of manipulation and/or trickery, is talk about qualitative data as though it were quantitative. One very important aspect of quantitative data is that there is an ordered relation on a given set of quantitative data, so you can make absolute and accurate claims about how that data is ordered. One person's height can be quantitatively shown to be higher than anothers, their weight larger, there top speed faster. And all of these properties can be shown to be undisputedly so, that's the nature of quantitative data.
And here's they key point: you can absolutely show that someone's IQ score is higher than anothers, but you cannot absolutely show that someone is more intelligent than another. There is not an ordered relation on the set of human intelligence.
Now I know what you might say "But surely someone with an IQ of 70 and and IQ of 170 can be shown to be different levels of intelligence". But these are extremes and I would argue you're still ultimately making an assessment based on obvious, qualitative properties of intelligence.
Take for example the property of "friendliness", which is qualitative. Now you and I can could probably come up with some ordering among people in a room as to who was the least and most friendly. But if we moved to different cities or countries that ordering might change. I would bet our extreme case would still hold, that is the person we decided was the least friendly, would probably (but not absolutely) be seen as unfriendly in many environments. We can compare to a degree qualitative data, but it is always fuzzy, and never absolute.
This is so important, and more than just pedantry, because it is a logical error to try to compare qualitative things with quantitative means. It leads to a variety of poor/wrong conclusions about data and situations. This is why it is essential to realize that the number of correct answers on an IQ test can be correlated to a variety of other quantitative data. We may associate much of this quantitative data with qualities of intelligence, but this is by no means the same as making the claim that we are measuring something which is, by our current definition, immeasurable.
Since it is used to judge one's abilities, it's hardly fair to use it as a practical measurement, just as BMI is impractical to use for judging a body builder's fat percentage.
Anecdotally, medication which I take for ADHD/PI doesn't permanently alter my brain's chemistry, yet my IQ takes a noticeable dive without it.
Of course bad sleep will affect your IQ, and it doesn't make it less reliable. Why? You brain is less reliable when you had bad sleep, and IQ is a measurement of its peak performance. If you're not at peak performance any given day, your results will show.
No one who does well on an IQ test likes to be told an IQ test means very little, keeping in mind that high IQ doesn't determine your success, or guarantee you any specific lifestyle.
IQ is more of a horoscope than it is a method of science.
Being able to reach your peak IQ potential consistently is part of the daily hygiene of eating well, sleeping well, exercising well. And it's also a question of making the effort. If I can't measure it, it means you don't reach it. Or at least not often enough.
On the other hand, I agree that it might be overstated. But having worked with people that don't have the best minds, you start to believe IQ is not just crap.
If I use a measuring tape to record the length of a piece of wood - unless I cut the piece of wood, or damage it in some way - this measurement will always be the same. In the cold, it might shrink and in the heat it may expand - but I can measure those variations and account for them using the basic laws of math. Can you do the same with IQ?
> But having worked with people that don't have the best minds, you start to believe IQ is not just crap.
It's not that I don't believe intelligence varies, I just don't think we have the ability to measure it - yet.
What about those taxi drivers who had enhanced brain regions for geographic knowledge? Kind of the same thing...
I fear people use IQ as an excuse for a (lack of) their success rather than face up to it and improve (or just accept and move on).
For example, eliminating childhood malnutrition can improve IQ significantly across whole populations. Isn't that something to be excited about?
eliminating childhood malnutrition
can improve IQ significantly
I suspect that people who ask about IQs say more about themselves than an IQ number says about any particular individual.
Plus, from a more useful perspective, we need to have some way of measure a parameter if we want to study it. If we were trying to compare the results of two different strategies to improve the intelligence, we would need a precise method to measure the intelligence of every individual.
As far as I know, the scientific community agrees that IQ is not a strong predictor of true "intelligence"...
And yet the start of this thread is a scientific study that looks at variations in IQ.
"Price and her colleagues used brain scans to confirm that these big fluctuations in performance were not random — or just a fluke. They evaluated the structure of the teens' brain in the early teen years and again in the late teenage years.
"We were able to see that the degree to which their IQ had changed was proportional to the degree to which different parts of their brain had changed," explains Price. For instance, an increase in verbal IQ score correlated with a structural change in the left motor cortex of the brain that is activated when we speak."
So, if there were structural changes in the brain that correlated with change in IQ score, then IQ likely tells us something other than "this person does this well or badly at IQ tests." Many people are very skeptical about IQ tests. As depressing as it is, the basic science behind psychometrics has been mostly stable for decades. Look up the work of Linda Gottfredson (sp?).
As for this particular study, psychometricians already knew that generalized intelligence (the so-called g-factor) crystallized in adolescence or early adulthood. The surprising thing about this study is how much change some of the subjects showed. Going from the fiftieth percentile to the ninety-something or, worse, going in reverse, is a big deal. The researchers behind this study should get more funding to continue their work.
[1] Only three or four. I'm sure there are lots of kids out there getting far more over-tested than I.
Depressing? Yes. That's just the way life is.
What is even more depressing is that some people think you can will yourself to be smarter, and if you don't, you are just lazy.
What this study seems to say is that IQ is more variable over time than first thought.
Perhaps the variability over time is itself hard-coded.
Regardless of the cause of this variability over time, I do hope that this study leads to more open-mindedness, and less labelling of kids based on early academic performance or single cognitive scores.
1. There are degrees of mutability; "changeable" versus "hard-coded" is a false dichotomy. For instance, I can increase my arithmetic ability with practice, but I'm never going to be able to improve it so much that I can diagonalize huge matrices faster than a computer.
2. Whether or not a belief is depressing has no bearing on whether or not it is true.
So I would reframe the question a bit: to what extent can IQ be changed? How reliable are the tests? And if we can improve IQ, what's the best way to do it? For example, childhood malnutrition can lower IQ, so improving childhood nutrition can pay off big. The Flynn effect -- the rise in IQ scores over time -- suggests that there are other things that can raise people's IQ as well, so if we can find and exploit those, and they actually raise intelligence, then that would be great.
Now, there is a flaw in the point that you can train for tests - if you trained in this task, then the task has no diagnostic meaning for you. But if you genuinely start working with more spatial reasoning gear - say you become a mechanic of some sort - you get better at recognising how things fit together spatially. You have, in effect, trained yourself to be better at spatial reasoning in general, and would do better at the subtest.
But the important thing to note here is that your intelligence has improved in that way - your ability to reason spatially has improved; you are actually able to cognitively do more than you could previously.
Likewise with the (culturally-referenced) verbal tests. Someone might get an IQ test at 20, then 'find books' and become a voracious reader. Tested a couple of years later, their vocabulary and verbal reasoning has been significantly exercised and improved. With an improved vocabulary, you are better able to express or consider more advanced concepts, so again, that aspect of your intelligence has actually improved.
Has it been tested whether training for the spatial reasoning tasks on an IQ test will make someone better at other spatial reasoning tasks (like being a mechanic)?
I don't know if you could say "would mean you would make a good mechanic" based on that one test because that involves other aspects, not just spatial reasoning, but being a mechanic would mean you (probably) deal with spatial reasoning more often than say a journalist or call-centre worker.
Anyway, clearly "IQ" isn't hard-coded. People get different scores on different days on different tests, and people tend to get higher scores over time as they get better at solving the dozen or so standard classes of problem that you tend to get (just ask me what this cube looks like unfolded!)
On the other hand, there is a very real phenomenon called "intelligence", and people have it to varying degrees (so do animals, to even more widely varying degrees), its effects are well known to everybody from our experience in the real world, and IQ tests are vaguely correlated with it. And it does seem to be largely genetic.