What do IQ tests really measure?


Ever since I can remember, IQ tests and what they are supposed to measure have been one of the biggest controversies in psychology. The one thing most people agreed upon was that, whatever was being measured, these tests did not measure "intelligence."

The latest explanation is that they measure a person's "motivation" and the likelihood of future success. And by "motivation" is meant that of the person being tested for taking the test itself.

Research carried out at the University of Pennsylvania by Angela Lee Duckworth looked for a correlation between IQ test scores and the motivation shown by the test takers - did they bother to finish; did they rush through the test just to be done with it; were they just going through the motions, having no real interest or belief the test meant anything, versus following orders, taking it seriously and thinking a high score would benefit them?

"When people use IQ tests in social science research, where thousands of kids are taking IQ tests where it doesn't matter to them what they get, what's the effect of motivation on those scores?" Duckworth asked.

What the research showed was that long-term outcomes could be predicted by these tests (higher economic and social status). "But," Duckworth said, "what our study questions is whether that's entirely because smarter people do better in life than other people or whether part of the predictive power [is] coming from test motivation." In other words, the IQ tests may be measuring motivation to succeed rather than raw intelligence. 

Then she asks, "Could it be that part of the reason doing well on this test predicts future success is because the kinds of traits that would result in you doing well - compliance with authority, self-control, attentiveness, competitiveness - are traits that also help you in life?"

Now "compliance with authority" and "self-control" (i.e. not being rebellious) may well be traits that exploited groups within society lack and thus are traits valued by mainstream society. It would seem the tests also measure docility as well as motivation.

Duckworth's conclusion regarding her study is that it "means that for people who get high IQ scores, they probably try hard and are intelligent. But for people who get low scores, it can be an absence of either or both of those traits."

So, if you get a low score, you are either not intelligent or not motivated, or both. It follows, however, that intelligent, even very highly intelligent, people could score low on the IQ test because they are not motivated to go along with the social regime in which they find themselves. Therefore IQ tests are unreliable measures of a person's "intelligence."

On the other hand, people who are docile around authority and take orders easily are likely to score high on the test compared to people who question authority and the status quo - everything else being equal - so the test's main use would seem to be as a tool used by the powers that be to identify and hold back people who might potentially challenge their monopoly and control of power.

The results of Duckworth's study suggests that progressives should object to the use of IQ tests on students and young people by the authorities in an attempt to classify their future behaviors.

Image: Oliver // CC 2.0

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  • I have a Ph. D. (done for University College Cork and externally examined by the University of Canberra) and a low IQ according to some tests I did. what do you make of that. I am of course useless at all those spatial questions on IQ tests.

    Posted by Jim O'Shea, 01/03/2015 1:05pm (8 months ago)

  • I have a Ph.D. and have written 6 books. I was also Principal of a large secondary school. Out of curiosity I did a number of online tests. I did well in one, scoring 112, but very poor in others (82). So I wonder how someone with a low IQ could have a Ph.D. (externally examined in the University of Canberra)? I do not believe that these tests are of great value. I have very little spatial or mathematical ability, and most of these tests measure little more than spatial ability. I have good emotional intelligence and am good with people. Having retired from school I am now a counsellor.
    what do you think?

    Posted by Jim O'Shea, 01/03/2015 1:00pm (8 months ago)

  • This isn't saying that IQ tests aren't measuring intelligence. Just that they're measuring MORE than MERE intelligence. Intellectual, Social, and Economic achievement are all tied into the common and much-celebrated practice of test-taking in education as the gold-standard for evaluating students.

    I took tests because I liked them, and I liked them because I always did insufferably well on them. NOT because I was told to and was "just following orders". Doing too well did not help me "conform". I broke the curve too often. I even joined a club where you can take tests competitively and loved every minute of it - despite butting heads with the coach on more than one occasion.

    I am particularly resistant to authority - this is a common trait among gifted students (who either have or would be expected to do above the 97th percentile - if IQ measured JUST intelligence). The once-a-week gifted class in my elementary school was less likely to "draw inside the lines" as a group than my normalized (artificially distributing high- and low-achievers, thanks federal policy circa 1998) classroom.

    So my opinion is "YES, testing measures intelligence" but that measure is confounded, or diluted, by the above factors (achievement motivation, following rules) and MANY MORE.

    The remedy is to take these factors into account and COUNT THEM AGAINST the score of the test-taker. For example, I knew I was of considerably higher intelligence than all of me high school peers because those right behind or even matching my grades STUDIED MORE and ASKED FOR MY HELP because even they recognized that it didn't look like I even tried. I didn't, because I never had to.

    My actual level of "Motivation" (and that of other would-be high IQ types) was less than it would appear by simply measuring my achievement on a test. Therefore, my lower motivation score (as a personality trait) should count TOWARD my IQ, just as my resistance to authority should. The FACT that I was at the top DESPITE these confounding factors gives a much more accurate picture of my IQ. Conversely, time spent studying as a measure of motivation and compliance as observed by real-life authority figures as a measure of obedience should be counted AGAINST

    Posted by Daniel F, 06/20/2013 3:30pm (2 years ago)

  • As I see an IQ test it gives a very good indication of where an individual stands compared to all those taking the test.
    Since LBJ's War on poverty and the Billions spent on education an IQ test should be a confirmer of who paid attention in class. We have had enough stimuli to debunk the IQ as a racist tool.

    Posted by Chuckwagoncharlie, 06/01/2011 5:42pm (4 years ago)

  • My IQ scores were always in the "genius" range. Therefore, I believe that IQ tests are, beyond a shadow of a doubt, !00% accurate, thank you very much!

    Posted by John Whiskey, 05/31/2011 11:04pm (4 years ago)

  • Interesting comments but in years past the Government gave IQ tests to those entering the military. I had friends who barely made it through H.S. .Their IQ tests placed them high enough to show they could learn complicated material and would qualify for OCS. Most went on to get Masters and Phds either in or out of the service. The IQ test told them they had the potential to succeed in learning complicated materials which they did in their career paths.
    While IQ test do not measure Desire they give a very good indication of the individuals ability to think rationally and solve complex problems.

    Posted by RiverRat2U, 05/31/2011 1:07pm (4 years ago)

  • well leandro a guess he showed his true intelligence. i hope for his sake he doesn't react that way all the time. in solidarity jim

    Posted by jim, 05/27/2011 4:50pm (4 years ago)

  • what about einstein? didn't he have a high iq? in solidarity jim

    Posted by jim, 05/27/2011 9:50am (4 years ago)

  • what about einstein? in solidarity jim

    Posted by jim, 05/26/2011 4:47pm (4 years ago)

  • It's getting closer to my personal definition "it measures the ability to conform to established knowledge" which i told a MENSA dude years ago and he punched me in the face.

    Posted by Leandro DellaPiana, 05/26/2011 4:17pm (4 years ago)

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