Does IQ really matter for presidents?

Last time I wrote about whether the most powerful person in the world should also be smart. This seems to have struck a chord with a number of people. I claimed that when considering presidential job applications, an Ivy League degree might be a good thing to look for. Matthew Atkinson, my colleague at UCLA took this a step further and analyzed Presidential IQ and success. He sent me this diagram.

 

 

This plots Presidential IQ against Presidential success. First let me talk about what we see here and then I'll give my two cents on what to make of it.

 

IQ is on the horizontal access and Presidential success is on the vertical axis. You can see that as IQ increases, Presidential success generally increases too. The Presidents for which there is consensus about their IQ are marked in red.

 

You may be thinking that it doesn't really look like much of a pattern - it is true that the relationship is far from perfect. Look at Andrew Jackson, for example: not on the high end of Presidential IQ, but among the most successful. In social sciences, we very rarely find relationships that are very exact. Political science is not physics. We cannot predict Presidential behavior like we can the behavior of an atom. The reason that the Presidents appear all over the plot is that, obviouisly, things other than IQ determine their succes. But you can see a general pattern here. It is clear that, generally, as IQ increases, so does success. In fact, Matthew has labeled the plot to show that, in cases where there is consensus about the IQ of Presidents, the correlation is quite high: .59.

 

Making this particularly fun is that he has plotted John McCain and Barack Obama. This shows how we would expect them to do, based on IQ alone. Time magazine claims to know McCain's IQ to be 133, based on old Navy records. That means that if McCain's success were to be predicted only by IQ, he would be very much in the middle, near some rather undistinguished company, by Presidential standards, like Chester A. Arthur, Rutherford B. Hayes, and George H.W. Bush.

 

What does this mean for Obama? Nobody knows because we don't know his IQ. Matthew has plotted him at three different levels. I'm sure some of you are convinced of his genius - you probably think that a 148 is far too low. However, if we put him there, it predicts he will be as successful as Presidents like John F. Kennedy, John Adams, and James Madison. But he just might not be that smart - we just don't know. Maybe you believe that Obama is closer to McCain, or even below him. These possibilities are plotted in the diagram too. We really just don't know.

 

There are some things we might want to consider when discussing whether big brains make for good Presidents.

 

Most obviously is that we really do not have an adequate measure of Presidential IQ. Matthew gathered his IQ scores from the work of the UC Davis pyschologist Dean Keith Simonton. Simonton, of course, never gave an IQ test to any President. In fact, in being based on old Navy records, McCain's score might be the most accurate score that we have. For all other President's, Simonton scored IQ by combining the work of scholars that have studied Presidential biography. That the scores are based on presidential biography gives me pause because it might be that biographers think that Presidents have high IQ's because they were successful in office. For example, do we think FDR was smart because he was a successful President or was he a successful President because he was smart? It is probably a little of both, which means that the causal relationship between intelligence and Presidential success might be overstated. If IQ measures innate intelligence, being President cannot cause a President to have a higher IQ, it can merely change our perception of their IQ, which in turn makes their success look more related to IQ.

 

It is also worth mentioning that IQ, like many measures of aptitude, is not without its limitations and one should be cautious in trying to predict individual success with such a measure. However, Matthew put it this way:

 

"Most presidents have had IQs around 130. Having an IQ over 140 may on average be worth about 10 points (give or take) in the presidential success rankings. IQ alone certainly is not enough to turn a Herbert Hoover (128) into a Teddy Roosevelt or a Lincoln. But perhaps if Hoover's IQ were over 140, he would have handled a difficult situation better and in turn be remembered as average rather than something of a bust."

 

Matthew also looked at the relationship between IQ and Presidential success while statistically controlling for previous experience. The result...IQ has a strong relationship with success. Previous experience does not appear to have any observable relationship with success.

 

I should also add, and this is the realm of pure speculation, that maybe the relationship between IQ and Presidential potential is curve-linear, meaning that maybe, if a person gets too smart, it begins to hurt their Presidential capabilities. Think about the smartest person you know - perhaps a college professor - would you really want that person to be President?

Comments

Nate Edelson says:

If you want to gauge a presidents intelligence, just look at the published letters. There's even a series bound in leather of some of the most important letters of our presidents. Further, 'raw' intelligence must always be countered with unadulterated common sense. Unfortunately, most people seem to be filled with 'common' sense. That's never enough, because this common sense fails in certain situations, and it takes intelligence of the 'rawest' kind to distinguish this detail and discern when thought-process must be tailored. So, yes, an Ivy League background may seem fitting, neither common sense, nor an Ivy League background will ever stand on it's own. You must measure each carefully. Here's a tidbit for you. You have never, ever, seen a man who can be this carefull with his words, and still communicate, as Obama!

YOGI BEAR says:

Obama: Occidental College - Two years. Columbia University - B.A. political science with a specialization in international relations. Harvard - Juris Doctor (J.D.) Magna Cum Laude Biden : University of Delaware - B.A. in history and B.A. in political science. Syracuse University College of Law - Juris Doctor (J.D.) vs. McCain: United States Naval Academy - Class rank 894 out of 899 (meaning that, like George Bush, McCain was at the bottom of his class) Palin: Hawaii Pacific University - 1 semester North Idaho College - 2 semesters - general study University of Idaho - 2 semesters - journalism Matanuska-Susitna College - 1 semester University of Idaho - 3 semesters - B.A. in journalism Hey BooBoo, vote for someone who is smarter than the average bear.

Richard W. says:

Can't argue with your comments here, other than the idea that you can objectively measure "success" (or, as pointed out in other comments, the IQ's of some of these leaders) and thus I'd greatly doubt "the data is valid". No, anecdotes don't demonstrate that conclusions are wrong, but they do make one question, yet again, the assumptions used in doing such research. My comments about judgement were to offer another quality in potential leaders that seems to be undervalued in today's discussion of presidential success. I don't want to disparage your scholarly efforts, but I believe your research underscores common beliefs about presidents at the expense of more important qualities readers may want to think about.

Ryan Enos says:

Richard - your points about Reagan and Carter are actually exactly what the plot here is showing - notice that Carter's IQ is rated more than 20 points higher than Reagan's, yet Carter's success if considerably lower. No President's success is predicted perfectly by IQ - but the correlation is there - we can't make it go away, as long as the data is valid. Pointing out that Carter is more intelligent, but less successful than Reagan, just like any other anecdote, does not mean the correlation is not true. What anecdotes like this do demonstrate, as does the plot, is that IQ does not predict Presidential success perfectly - as I noted above. Judgment might very well be a very important factor in ranking a President - unfortunately, to my knowledge, we don't have any scientific measure of judgment, unlike IQ. Judgment though could be one of the many factors that is contributing to the imperfect correlation between IQ and success.

Richard W. says:

Skeptics are right to question this correlation, as most recently observed in the presidencies of Carter and Reagan. Carter was correctly know as highly intelligent, and his presidency one of the least "successful" by any measure. Alternatively, Reagan was never described as "brilliant" (who knows?) but was considerably more successful by any yardstick. More interesting, to astute observers, is academia's obsession with intelligence as it relates to presidential "success" (still beating the GWBush is an idiot drum). Here's an alternative to consider and study (with about as much chance as being objectively assessed): JUDGEMENT: a characteristic grossly undervalued in assessing presidential timber. Reagan had it "in spades" while Carter seemed to lack it. Perhaps we can add this element to our discussion of what makes successful presidents, and maybe even start using it when we go to "pull the lever".

Matthew says:

SFG, There is no evidence of liberal bias in the major rankings of presidential success. There are two ways to check this. First, political science scholars who specialize in scaling voting data have estimated the ideological locations of the different presidents (see voteview.org for the details). The correlation between the ranking of presidential success and conservative ideology is .17 -- not a big relationship but not one consistent with liberal bias. Second, we can see how the different rankings compare with the one ranking that is clearly not inclined toward liberal bias -- the ranking carried out by the Federalist Society (conservative legal organization) in collaboration with the Wall Street Journal in 2005. Surprisingly, the Federalist Society's ranking has the lowest correlation with conservative ideology (likely due to their explicit efforts to produce an objective ranking), which would indicate that if anything these rankings MAY have a conservative bias.

Ryan Enos says:

SFG - no doubt, bias, liberal or otherwise would be a difficult thing to avoid if one were to rely on self generated subjective rankings of Presidential success - which is why subjective personally generated rankings were not used. I don't how one would generate objective rankings. I am not sure what Matthew used to generate these rankings, but they fall in line with the rankings that I used previously. You can see my previous blog post for a more extended discussion. The rankings are generated by a composite of rankings of historians and the general public, a disproportional amount of which came from the Wall Street Journal, which you know is not noted for liberal bias.

SFG says:

Um, how do you measure presidential success? LBJ was more successful than Reagan? Like failing to succeed in his War on Poverty and dragging us into Vietnam? Reagan won the Cold War and decreased the size of government, which were both things he set out to do. And Jefferson may have done a lot for this country in other capacities but he was a pretty poor President, having us embargo ourselves and all. What did JFK do that was so wonderful? Almost got us blown up in the Cuban Missile Crisis? I hate to call liberal bias, but you have to admit it's a pretty difficult thing to avoid when rating Presidents.

Matthew says:

JFK's rumored modest 119 IQ is or course a well known legend. But the 119 number is extremely questionable. I believe JFK likely did take an IQ test at Choate prep school which resulted in the 119 score. But one of the Kennedy biographies reporting this number (Michael O'Brien's) notes that the school determined based on this test result that JFK's academic ability ranked in the top 20 percent of their student body. This makes the 119 IQ number implausible: Choate is as selective as the Ivy League colleges and is probably more academically demanding. If its median IQ were 119, that would place the median Choate student around 100. It's almost impossible to believe that vast numbers of Choate students could get through that school -- even if they could get in -- in spite of sub-100 IQs. Conclusion: Don't put too much stock in teh legendary 119 number.

Ryan Enos says:

Arthur - I have seen claim on that, but I have not done the research to see if it is credited to a reputable source. Nevertheless, the estimate of Kennedy's score here comes from Simonton's list and is methodologically consistent with the other scores.

Arthur says:

You are mistaken: Kennedy's IQ was announced as 119 over forty years ago; go back and check the records-A

Ryan Enos says:

sceptic - you're right, there is certainly uncertainty, as we almost always see in social science, but the correlation is strong and intriguing and holds up in the face of at least one control. From the perspective of prediction, IQ might not be a bad tool. The IQ of the long ago Presidents, just like the newer ones, is based on in-depth biographical study, from the work of Simonton, as I note. To the extent that there is error in this measure, as there surely is, it makes the fact that there is such a strong correlation even more intriguing. Presidential success is a measure of historical rankings - if you look at the ratings, you might find they are probably acceptable to most people. But, as I noted in the blog, these might be problematically reflected in the IQ scores. For a more in-depth discussion, you might see my previous blog here http://newsroom.ucla.edu/portal/ucla/election-blog-post.aspx?id=1213 .

IQ sceptic says:

So what? I'm really not sure what this graph is supposed to show. There's just too much uncertainty both in the x and y axis. How on earth can you know the IQ of presidents like Lincoln or Jefferson who died long before the concept of IQ was even around? And how do you measure presidential success?

Ryan Enos says:

Hex - as the plot indicates, most people would agree with you that Carter was not a great President. However, this does not mean that IQ doesn't matter. As you say, and the plot indicates, Carter does not fit the trend of the relationship between high IQ's and good Presidents. However, most Presidents do - this is why we do tests like this, to look for general patterns rather than anecdotal cases. What is interesting about this, is that even in the face of controls for experience, IQ still seems to matter for the quality of a President.

Hex says:

Carter was the absolute worst Presdient of all time......if he is at 150, IQ doesn't matter. I think there should be a common sense rating. Carter continues to embarass the United States.

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