It’s hard to measure people strictly by their IQ, because not everyone has the same health challenges, not everyone has a stress free life due to their socioeconomic conditions and so on, however if we just looked at an average generic representative of a person with 80 iq points, 100 and 120, how big would a difference between them be?
For example could a healthy and stress-free person with an iq of 80 get a PhD and could a person with 120 points end up working as a janitor, assuming they don’t have any logical reason to do so and aren’t forced into it by unemployment, health, adhd or any other issues, but simply because they were struggling with education?
I’m far from an expert in this area, so many will come along with better and more factual answers, but one thing I do know is that IQ tests are a very subjective measure of intelligence, and do not do a great job at highlighting or predicting those who will be successful in life. Some people are just better at taking tests and therefore will score better on an IQ test than someone else of similar intelligence.
Also pure intelligence is in no way a guarantee of success in life. Per your example, I’m sure there are many janitors who could score 120 or more on an IQ test. And there are many people who may not do as well on an IQ test who have the drive and strength of spirit to be very successful at whatever they do.
IQ, by itself, is fairly meaningless. It’s a quick-and-dirty shorthand that can inform - but not solely determine - the way an educator approaches a pupil. Saying “this kid is smart” or “this kid is slow” helps exactly nobody. A child who may need special help in school will receive a full psychological evaluation, of which an IQ test will be one component.
For most adults, IQ means exactly jack shit.
There’s a lot to unpack here, but a good bottom line is that there’s nothing wrong with being a janitor.
Very true, and rereading my answer, I realize I may have unintentionally been implying that as well in my reply. Yes, there’s nothing wrong with being a janitor, or any other honest working job. I was just trying to make the point that a tested IQ of 120 or more doesn’t automatically guarantee one will get a PhD and go on to become a theoretical physicist or rocket scientist.
I hope that was directed at my more clumsy reply and not Johnny_Bravo’s, which was a better answer and did not imply any of that at all. IQ is a rough estimate of where a student’s aptitudes may lie, but is not, in and of itself, a guarantee of anything.
Those are all important things that IQ tests are not great at measuring, and especially aren’t great at measuring in a vacuum.
You, like many people, are putting far too much weight on a number that, at best, tells only a fraction of any person’s story. An adult who says “I scored over 120 on an IQ test” isn’t saying much beyond “I did reasonably well on a particular standardized test.”
Someone with an average or below-average IQ could certainly get a PhD, in something. There are lots of examples of people possessing doctorates who I would not trust to empty piss out of a boot with instructions printed on the heel, to use a colloquial expression.
The odds of getting a PhD in a competitive field of science and having a productive research career with a reproducibly measured IQ of 80 would likely be poor.
Only tangentially related to the topic - I play a bunch of different games on my tablet - word games and matching and patterns - and since they’re freebies, they have ads. Lots of the ads are for games that supposedly measure or raise your IQ. Two I find particularly amusing - passing level X on Game Y means your IQ is 160!! OMG!!!
The other ad is for a game that apparently measures your IQ in %. My brain hurts just trying to figure that one out.
I didn’t mean you implied that at all, just that when you replied to the OP that there’s nothing wrong with being a janitor, rereading my reply it read to me as it could be taken to mean being a janitor is not being ‘successful’. So I just wanted to set the record straight.
When my younger son was around 14, he found what he figured to be a genuine free IQ test online. He scored 150, and was very proud of himself. Like most teenagers, he figured he was much smarter than his old man, so he wanted me to take the test too. Lo and behold, I also scored 150! He was pretty unhappy and immediately declared the test to be a scam.
Forget about whether I.Q. actually means anything. All you need to know is that a test measuring something or other is given to a lot of people, whatever scoring well on that test means. Then distribute the scores on that test on a normal curve. For these purposes, we’ll say that the mean of the normal curve is 100 and the standard deviation is 15. This means that someone who has been given the location of 100 on that normal curve has scored better than half the people who took the test and worse than half the people who took the test. Someone who get the location of 115 on the normal curve has scored better than the bottom half people and in addition better than an additional .3149 of the people who took the test. O.K., then use this table for figuring out what a position on the normal curve means:
So, for instance, a position of 152 on the normal means that that person scored better than the bottom half (50%) of those that took the test, plus that also scored better than (52 / 15) times = (approximately) 3.47 standard deviations on the top half. Look at the table. 3.47 (3.0 on the side of the table and .07 on the top of the table) is .4997 in that row and column. So that person scored better than 50% plus 49.97% of the people on the test. 50% plus 49.97% is 99.97% of the people. So they scored better than 99.97% of the people on the test. So an I.Q. of 152 means that they scored better than 99.97% of the people who took the test.
But does that test actually measure anything? Who knows? Does anything like I.Q. actually exist? Who knows? All we can say about an I.Q. score is that it measures how well someone has done on a particular test.
Online tests are inaccurate and often scams. If you want an even vaguely accurate I.Q. test, go to a psychologist who specializes in I.Q. tests and have them test you (which will cost money). Tests you find anywhere else online or in a book or in a magazine or whatever are too inaccurate to be useful.
Yeah, I realize that; my story was a humorous attempt at making that point. A 14 year old and a 50-something year old, with very different education levels and life experiences, both take the same IQ test and both score exactly 150? Yeah, a wee bit suspect. I guess I should have said my son immediately realized the test was a scam, instead of ‘declared it to be’. It was just funny how shocked he initially was to see my score result was exactly the same.
My son is actually very intelligent, and he probably would outscore me in a real IQ test. The one he found online did seem realistic in terms of the questions, but I’m guessing it was set to give a ‘150’ score to anybody who did reasonably well at the test, and it probably had a link to a more in-depth test one could take for a ‘small fee’.
An IQ test is a very one-dimensional measurement of one particular set of intellectual skills. I know lots of kids who were in gifted programs who never amounted to much because of lack of motivation, and kids who didn’t find school easy but got great grades because they were willing to spend twice as much time studying as anyone else. Artistic ability, interpersonal skills…the list of important things IQ doesn’t measure could go on and on.
Still, especially at the extremes, there’s a certain predictive value. There are six-foot guys playing in the NBA, and seven-footers who can’t, but obviously height still matters a lot. At the high end of the IQ scale, there are all sorts of things that could trip you up and leave you living in the streets. At the low end, though, I would doubt that anyone with a replicated IQ much below average would be able to get a PhD (though they might be very successful in life if they have other skills to compensate).
I’m not an expert, but I don’t think in everyday life situations you’d be able to tell the difference between someone with a 100 or 110 IQ; around a twenty point difference is about where I’d expect it to be noticeable.
@Wendell_Wagner and @pulykamell have correctly explained that IQ’s are supposed to follow a normal distribution, and what that means for the OP’s question.
I’ll add that, historically, IQ was originally intended to measure mental development in children. It was supposed to be “mental age” divided by chronological age, times 100; that’s why it’s called a quotient.
So, hypothetically, if “mental age” were well defined and could be accurately measured, a 10-year-old with an IQ of 110 would have the mind of an 11-year-old; a 10-year-old with an IQ of 80 would have the mind of an 8-year-old; etc. (I’m not sure how or whether this conception would apply to adult IQs.)
A person with an IQ of 80 would appear noticeably ‘slow’ to those with an average or above IQ. Joining the military requires an IQ equivalent of at least 85 for a recruit to be able to accomplish the tasks required of an infantryman in a reasonable time.
A person with an IQ of 80 will not earn an advanced college degree and may not even be able to finish high school. To become a doctor will generally require an IQ of about 120 or so; maybe a little less for a very motivated hard worker, but not a lot less.
I have a long time friend from school who has a very high IQ (over 150), got perfect scores on the SAT, and has a master’s degree in electrical engineering (from a very good school, not a diploma mill). He retired after 40 years as the school janitor.
