Saturday, January 22, 2011

Average IQ by occupation (estimated from wordsum scores)

Because it does not appear to be posted anywhere else on the web, and because it was such a tedious slog to put together (a labor like this isn't going to just sit unexposed in an excel file!), the following table shows IQ by occupation as estimated from GSS wordsum scores. The mean wordsum score for native-born whites is assumed to correspond to an IQ of 100, with a standard deviation of 15.

Sample sizes are not sufficient for statistical significance for a host of job categories (as long as the respondent pool is plural, it is included), and the usual disclaimer about a ten question vocabulary test not correlating perfectly with IQ (Razib reports an r-value of .71) applies. Women tend to do slightly better on verbal measures of intelligence, while men do better on quantitative measures of the same. Calculated from wordsum scores, women enjoy a bit less than a 2 point IQ advantage over men, so heavily female occupations like teaching are slightly overstated and heavily male occupations like those involving engineering are similarly understated. To avoid issues of English language proficiency, only those born in the US are included. Because a perfect score translates to an IQ of 128, high-end wordsum scorers encounter an artificial ceiling on their purported IQ. So, to a much lesser extent, do low-end scorers, as missing all ten items corresponds to an estimated IQ of 53. Consequently, the table is merely suggestive, not definitive or statistically rigorous:

1. Mathematician117.14
2. Physician117.048
3. Geologist116.75
4. Meteorologist116.72
5. College professor115.989
6. Author115.158
7. Librarian114.628
8. Attorney114.5102
9. Biologist113.78
10. Optometrist112.93
11. Statistician111.42
12. Computer systems analyst111.385
13. Judge111.03
14. Psychologist110.320
14. Actor110.320
14. Dentist110.316
14. Chemist110.311
18. Museum curator110.14
19. Clergyman108.938
20. Pharmacist108.711
21. Teacher108.1297
22. Agronomist107.96
22. Electrical engineer107.946
24. Stockbroker107.831
25. Fine artist107.433
26. Physical therapist107.440
26. Sociologist107.44
28. Economist106.621
29. Mechanical engineer106.535
29. Architect106.526
31. Real estate agent105.780
32. Commercial airline pilot105.612
33. Dental hygienist105.533
34. Social worker105.0109
35. Registered nurse104.9238
36. Stenographer104.644
37. Government official104.177
37. Insurance agent104.177
37. Computer programmer104.141
40. Accountant104.1168
41. Civil engineer104.023
42. Undertaker103.68
43. Jeweler103.25
44. Secretary103.1430
45. Engineering technician102.655
46. Police officer102.581
47. Industrial machine repairer102.49
47. Photographic process worker102.46
49. Debt collector101.710
50. Sales representative101.6134
50. Compositor/typesetter101.68
52. Fashion designer101.47
53. Photographer100.819
54. Receptionist100.8104
55. Machine tool operator100.67
56. Veterinarian100.45
57. Communications equipment mechanic100.29
57. Broadcast technician100.29
59. Glazier99.33
60. Mail carrier99.168
61. Retail salesperson99.0368
62. Telephone operator98.741
63. Dressmaker98.418
64. Bank teller97.867
65. Licensed practical nurse97.573
66. Plumber97.366
67. Maid97.1107
68. Waiter/bartender96.5289
69. Aircraft mechanic96.321
70. Barber96.2117
71. Data entry clerk96.053
72. Carpet and tile installer95.8143
72. Painter95.851
74. Child care worker95.4181
75. Tool maker95.353
76. Telephone installer/repairer95.110
77. Security guard95.026
78. Farmer94.711
79. Bus driver94.645
79. Firefighter94.642
81. Insulation installer93.95
82. Cashier93.8290
83. Furniture upholsterer93.713
84. Electrician93.666
85. Taxi driver93.576
86. Bookbinder93.05
87. Welder92.763
88. Automobile mechanic91.6131
89. Dietitian91.59
90. Truck driver90.6216
91. Railroad conductor90.47
91. Sailor90.43
93. Bricklayer90.322
94. Cook90.3140
95. Construction worker90.0139
96. Roofer89.316
97. Sheet metal worker88.544
98. Carpenter87.43
99. Janitor86.982
100. Drill-press operator86.72
101. Forklift operator85.842
102. Butcher84.321
103. Concrete worker82.98
103. Surveyor82.92
105. Shoe maker/cobbler79.66
106. Lumberjack75.38

GSS variables used: ISCO88, WORDSUM, BORN(1)

Parenthetically, follow AE on twitter @AudaciousEpigon.


FuturePundit said...

These results make me skeptical of GSS wordsum as a good proxy for IQ. I have a hard time believing EEs and MEs have average IQs below 110 or even below 115. The scores of commercial airline pilots and RNs seem too low as well.

I think of La Griffe Du Lion's Smart Fraction Theory cut-off around 106 for people who contribute to a higher per capita income. Difficult jobs are above that level.

ironrailsironweights said...

Of course there's just an n=2, but there is no way in creation that a person with a score of 82.9 could function as a surveyor. And 100.4 for a veterinarian simply boggles the mind.


Audacious Epigone said...


Well, a vocabulary test is going understate the IQs of engineers (and presumably, mathematicians, despite their still being at the top of the list) more than just about any other occupation.

Perhaps you're correct, but I think we in the steveosphere (or HBD blogosphere or whatever you'd like to call it) and your overlapping but distinct futurepundit readership are way on the right end of the curve, even among colleagues of the professions we're engaged in (which are mostly white collar/professional). In the case of mechanical engineers, for example, the median wordsum test taker (born in the US), missed three of these ten words. Among physicians, half missed at least two. I'm skeptical that the average doctor or college professor does not know what the words "allusion" and "emanate" mean, but that is the reality.

Re: the smart fraction theory and RNs inclusion in it, that means fewer than 1 in 10 blacks meet the cognitive requirements to be nurses. That isn't the sense I get from what I've seen.


Yes, those sample sizes are obviously highly unreliable. But there are surveyors out there, somewhere, born in the US, who missed half the words shown at the link to Inductivist's post where he reveals wordsum's contents.

Steve Sailer said...


It's a low stakes test so people probably put less effort into checking it twice, which tends to compress scores.

You might be able to estimate the impact of the restriction of range problem by looking at the 10/10 scorers for different groups to see if there are more of them than, say, 9/10 scorers.

The rank order seems pretty good, although biased against quant types by being a vocabulary test.

Jack said...

Besides the obvious low relative scoring of engineers and accountants, and high relative scoring of teachers, I noticed that cops scored a pretty significant 8 points higher than firemen. It usually seems that both groups usually are estimated at similar IQ's, so i found this interesting.

FuturePundit said...


I think psychometricians have collected a lot of data on IQ and occupations. If you go to this PDF on page 3 you will see occupations of white enlisted men in 1945. You can also see another table on page 58 of this document by Linda Gottfredson.

But these tables lack many modern job categories. I'd like to see different engineering fields and assorted IT jobs listed.

Audacious Epigone said...


The numbers from 1945 appear to really be inflated, but I think rank order is more important than converted score. I agree with your thrust, but another source is rarely a bad thing, and since I did the legwork, I figured I might as well let everyone else take a look at it.


Yes, I noticed that as well and almost included it in the body of the post. The sample sizes for both are sufficiently large, making it a curiosity that's not easy to just blow off as the product of randomness.

FuturePundit said...


1945: The lower skilled occupations had smarter people in them because few of the smarter people had switched to cognitively demanding occupations yet.

Steve Sailer said...

The 1945 scores are from white enlisted men in the Air Force. I suspect the Army Air Corp got a lot of applicants and was fairly selective compared to the Army. On the other hand, Air Force officers probably scored even better on average.

Joseph said...

I suppose the table means that if you're a lumberjack, that's not okay.

Anonymous said...

sociologist > engineers

you gotta be joking

eeddy said...

> Lumberjack 75.3
That one also seems meaningless. 75 is basically retarded, and I think in general, instead of having 'simple' jobs, retarded people tend to simply not work at all, certainly not in as dangerous a field as lumberjacking.

dylan said...

How anyone could think a ten question vocabulary test shows IQ is beyond me. While my IQ is reasonably high I easily aced the wordsum test because I read a lot. Also wordsum supposedly correlates with adult IQ which is much less valid than child IQ because of education levels. It's pretty obvious for example, that people with English majors would regularly outscore people with science majors. This seems like common sense, but apparently it isn't to people that think this is an IQ test.

Unknown said...

as someone pursuing a career as a firefighter, your list is definitely inaccurate.

Matko said...

Why no philosophers on the list?

Anonymous said...

Where are the physicists?

Anonymous said...

no lawyers?

Anonymous said...

That's engineering: a bunch of pretentious morons.

Anonymous said...

Absolute garbage - Surveyors third from bottom? People who measure, manipulate and present data lower than the labourers and sales people above? Nonsense.

Huge gaps, so many other professions not mentioned. Engineers should be a lot higher up. Design Engineers that is, not people who mend washing machines.

Christopher Fornesa said...

This list does seem plausible to me since studies have shown that the average college graduate (four year university) has an IQ of around 115. Other studies show average IQ based on GMAT, GRE or other scores for entrance into master's or doctoral level programs which is fairly inaccurate since most likely, those who enter these advanced programs have developed higher capabilities and mental capacities that would allow them to even have a chance at graduate school. Those tests aren't like the SATs, the average test-taker of those particular examinations are above or around the average for college grads.

Also, IQ isn't actually a definite (or accurate) measure of intelligence or even capacity, it only measures your ability (at the time of testing) to problem solve or show how the educational system has taught you. It has little to do with skills like level of creativity and others that employers often look for in potential candidates. Although IQ can be used to measure a level of cognitive ability, saying that just because you have a high IQ, you'll be successful or because you have a lower IQ, you'll only do menial jobs, is just a sorry excuse for not working hard!

People should remember that averages are just what they are, averages. I mean if you're a male who's 5' 8" and the average is 5' 9", you're supposed to be short when the global average for males is 5' 7"? Not necessarily! Averages are only relative, from height to weight to IQ that's all that's really true about these things.

Toby Crane said...

I can not say I agree with this because my brother is studying to be an electrician and he is super smart. He just likes working with his hands. Plumbers also have great knowledge of many things. In Allentown, there is great work to be done in the plumbing industry.

Anonymous said...

Worthless chart, garbage in, garbage out.6494iticipGe

Anonymous said...

I would bet that there is a very strong association between the degree to which people commenting here think the chart is accurate and their own placement in it. Also, don't discard it because you know a guy who is an "x" and he's really super "y." That's dumb. (Personally, I trust averages more than your personal, anecdotal evidence based on an even smaller sample size and in comparison with nothing.) Finally, read. No one is saying the measure is flawless. The one reported correlation between WORDSUM and a better measure of IQ is around .7. That's a strong correlation, not a perfect one. If lumberjack were at the top, sure...there would be a massive problem. It's not. The general placement seems about right, but there do seem to be a few non-intuitive results, perhaps due to small n. Then again, maybe I should NOT trust my own, personal sense of the relationship between IQ and occupation more than this.

Anonymous said...

Some of the people I have met have been people who are not in work. They are remarkable in all areas. The only thing which I have noted is that most people who are out of work are too clever to be employed as they would be a threat to the people who give them a job, and make them look bad, or rock the boat, with better and brighter initiatives, upsetting the apple cart, for the people who think by we are paid by the hour, and not by the time and motion study. Therefore Council HR depts. will not hire unemployed people and only poach people already in employment and di not rock the boat.

Anonymous said...

Here is more accurate data from University of Wisconsin.

Better spread with standard deviation for each job.

Ivan Shekerev said...
This is the best researched article I have encountered on the subject.
If you know any 140+ IQ people please tell them that we need to write for us. My e-mail is

Anonymous said...

The biggest problem I can see with this list is, not surprisingly, in my own profession. This chart lists:

Machine tool operator, IQ=100.6, n=7
Tool maker, IQ=95.3, n=53

The overall average doesn't strike me as unreasonable, but the distribution of the two categories does. Tool makers are, in fact, a small subset of machine tool operators, and invarriably representing the top level. I'm as suspicious of these two categories as I would be if I saw physicians greatly outnumbering nurses, while scoring significantly lower.

I suspect that these professions, and likely all of them, are self reported. In my experience working with and hiring machinists, and being one, I've found that greatly inflated resumes and and job titles are the norm. Everyone says he's a tool maker. No one says he's a button pusher. But the latter outnumber the former several times over.

As such, I'd be inclined to combine any categories where title inflation is likely. Retail salesperson/cashier, communications equipment mechanic/telephone installer repairer, and secretary/receptionist, among several others, seem like obvious examples.

Voice of Hope said...

This cannot be true. We are all intelligent in our own ways.
The hands cannot say to the feet, I am better than you in everything.
We were designed uniquely for different reasons by The Creator.
Don't believe, this believe God.
Be the best you can be with God.

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bozo de niro said...

The Audacious Epigone didn't even bother to define his terms including IQ and n.

Ben Bonarigo said...

I would love to see the person that could get into medical school with a
117 IQ. Distinctly recall the class being told that we had scored in the 92nd percentile or higher on MCAT and the average IQ in the class was 136.

Anonymous said...

Hahaha, I am a lumber jack with an IQ of 135.

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John said...

These are all bullshit by the way. 117 IQ is probably what a high school or college math teacher reading from a text book would have. Some guy on 4chan could have a 250 IQ by merely understanding war is orchestrated by greedy degenerates bound to the monetary construct or that religion is an irrational belief structure built on fear and social denigration. Anyone with a background in neurology, psychology, and science can have a maximum IQ.

People tend to think that the more technical things you know, the higher your IQ should be. This is false. You might be able to manufacture a lense part for a camera, but that doesn't mean that you can build an entire camera. You can be Elon Musk and pay people to run your company or design your ideas, but that doesn't mean you are smarter than einstein.

Simply, to have a high IQ you must have unique solutions to unique problems, which can't taught in school because they make teachers morally and ethically uncomfortable.