Ten Miles Square


September 29, 2011 9:12 AM Misleading Predictions About Why Obama “Can’t Win” in 2012

By Keith Humphreys

In another edition of how misunderstanding statistics can lead to misleading political predictions, let’s talk about base rates, predictive power and presidential re-election. In psychiatry, there is a fun logical problem in which students are asked to generate an instrument that will accurately classify people with and without schizophrenia in a sample of the population. Students draw up elaborate series of questions and diagnostic procedures and sometimes do as well as being right 95% of the time. But those approaches are all inferior to a different diagnostic system, which classifies all people as non-schizophrenic without bothering to ask them anything. Because only 1% of people have schizophrenia, such a system is correct an impressive 99% of the time. When you are trying to predict something with a very low base rate, most of the time you make a positive prediction (e.g., this person has schizophrenia) you will be wrong, and most of the observations you make about the group for which you make a negative prediction (e.g., this person doesn’t have schizophrenia) will be true but have trivial predictive power because they are true of almost everyone.

Now consider a far more rare condition than schizophrenia: Being elected President of the United States. Only 43 of the hundreds of millions of people who have been U.S. citizens have been President, and an even more infinitesimal fraction of the U.S. population has been re-elected President. This incredibly low base rate opens the field for many predictions that seem on their face to show great historical understanding and political acumen but are in fact of dubious value.

For example, do you remember that George H.W. Bush was not going to get elected because no sitting Vice-President had been elected President since Martin Van Buren? At that point, 39 people in U.S. history had been elected President, of whom 3 were sitting Vice-Presidents. This success rate compares very favorably to the chance of the average American, or the average politician or even the average politician seeking the Presidency. It would have been more reasonable to say that as a sitting Vice-President George H.W. Bush was unusually well-positioned to be elected President.

The G.H.W. Bush prediction also illustrates another tactic of faux-sage prognosticators, namely shaping the frame of reference to make the statistic more extreme. The U.S. had elected and re-elected former Vice-President Richard Nixon in living memory, so the ominous G.H.W. Bush statistic was artfully limited to “sitting” vice-presidents. And the time frame was chopped off at Martin Van Buren to misrepresent the full picture of U.S. electoral behavior; two other sitting Vice-Presidents had been elected before MVB. It’s a bit like saying Rick Perry cannot win because for the first 223 years of our history no Governor of Texas ever became President.

Fast-forward to President Obama, whom you may have heard cannot win in 2012 because no President has been re-elected with high unemployment. After it was pointed out that FDR and Ronald Reagan were both re-elected with high unemployment, the shocking historico-statistical proof of Obama’s political demise was re-framed to “No President since World War II other than Ronald Reagan has been re-elected with high unemployment”. But so what? Only 5 people have been twice elected President since World War II, and an infinite number of things is true of all the people who haven’t.

No one who wasn’t from California, Texas or Arkansas has been re-elected President since World War II (Doom for Obama!). No one whose last name starts with an O has been re-elected President since World War II (Double doom!). No one who was African-American has been re-elected (Triple Doom! Hey wait a minute, how did he get elected the first time…he was African-American then wasn’t he?). At least President Obama can take comfort in the fact that every single left-handed President who ran for re-election since World War II has won, as long as you don’t count George H.W. Bush.

[Cross-posted at The Reality-Based Community]

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Keith Humphreys is a professor of psychiatry and behavioral medicine at the Stanford University School of Medicine.


  • Greentaxman on October 01, 2011 1:49 AM:

    You forgot to mention that no President first elected as a sitting US Senator has been re-elected in either the 20th or 21st Century.

  • Ed Whitson on October 01, 2011 1:50 AM:

    You're whistlin' pass the graveyard, dude.

  • Keith Humphreys on October 01, 2011 8:13 AM:

    Note from the writer: An alert reader pointed out to me that at the time G.H.W. Bush was elected, 39 people had been President, but only 34 of those were elected. So the odds of a Sitting Vice President of being elected president were even better then that I stated in the post.

  • markg8 on October 01, 2011 2:21 PM:

    We're gonna be whistlin' pass the graveyard full of dead Republican presidential ambitions next November.

  • Ed Whitson on October 02, 2011 1:05 AM:

    Keith, anyone who doesn't recognize the close relationship between unemployment and presidential popularity is whistlin' pass the graveyard. I think Obama can still win, but articles that pretend his troubles are overstated are not useful.

  • Lance on October 02, 2011 2:10 AM:

    Remember, no white presidential candidate has EVER defeated a black incumbent for the presidency.

    So, of course, Obama will win.

  • Darsan54 on October 02, 2011 7:34 AM:

    Thank you for this little bit of enlightenment. I read these stupid predictions and get worried like everyone else. It's nice to have a better context of understanding in which to put the information.

  • Anonymous on October 02, 2011 2:51 PM:

    ed whitson,

    you're missing the point dude ...

  • Glen Tomkins on October 03, 2011 10:32 AM:

    Well, if the reasons I am pessimistic about Obama's re-election chances were based on statistics, I would be awfully encouraged by this article. But they're not. I'm more worried by the fundamentals.

    Why would swing voters stay with an incumbent who had failed to reverse abysmal unemployment rates? I can give you an answer for Reagan, that the numbers, while still bad, were clearly on the mend by Labor Day 1984. I can give you an answer for FDR, that he had the luxury of following the clearly smartest Republican of that time, Hoover, whose response to a Wall Street crash led to 25% unemployment. FDR was open with the electorate about the difficulty of achieving anything quickly, the need for new solutions just to tread water -- and Hoover's recent really disastrous results made the electorate settle for continued unemplyment at a merely disastrous, but stable, level. The electorate rewarded that honesty with continued support despite the lack of dramatic improvement.

    What's Obama's explanation for why unemplyment is still hovering near 10%? He had the misfortune to be elected in a time sequence closer to Hoover's than FDR's, in that he came into the WH just after our equivalent to the Crash of '29, and has had to preside over the dismal employment consequences, analogous to Hoover's term. But instead of making any reasonable attempt to cope with this bad timing by being open with the electorate about the difficulty in getting unemployment down quickly, despite all early indications that this was not going to be the typical 2-year recession we've seen since the Great Depression, he's been as serenely confident as Hoover about the success of policies that have now proven to have not worked. He settled for a stimulus too small to get the job done. Even if he had to settle, didn't have the votes to do better, no one forced him to pretend that the package he could and did get was just right, would surely work. It wasn't and it hasn't. How does he regain the confidence of the electorate in that trickiest of tasks for a politician, explaining away failure? How does he do that, how does he sell somber realism, after having been part of the chorus of mindless confidence?

    I don't see how he does that, and that, not the statistics, is what has me worried about his chances.

  • Crissa on October 04, 2011 1:01 PM:

    If you think Obama is Hoover, I've got a bridge to sell you.

    Did America vote in a do-nothing Congress in Hoover's term?

  • Philip Avon St. Cyr on October 15, 2011 9:09 PM:

    I respect your comments, Glen, but I think you've been selectively perceptive when it comes to Obama's remarks about his successes and failures. I also think you may be downplaying the precarious state of the market in Obama's first 18 months in office. Not only Obama, but also Bernanke and Geitner danced around the truth -- but there are times when the truth can create panic and chaos, especially in this internet age AND with a historic president who not everyone could be rational about accepting.

    IMO, it is somewhere between hard and impossible to fully explain the actions and statements of this administration. I think we will discover that some folks got it right (about what drove certain policies and practices), while others and/or everyone totally missed it because there are things no one not on the inside can possibly know.

  • gjdodger on October 16, 2011 12:42 PM:

    One other point. No sitting president has ever been reelected president 13 months before the election. Chill, doomsayers. Obie has a bunch of dough to spend.

  • Jonathan Burrs on October 17, 2011 3:07 PM:

    Nice article as well as comments. Very comical. :D

  • valleyforge on October 24, 2011 6:31 PM:

    You're equating the economy/re-election relationship with trivia about a candidate's biography? The "no president since Roosevelt has been re-elected with unemployment over 7.2%" sound bite may be oversimplified, but it is a tautology that a president is unlikely to be re-elected if the majority of voters feel things are bad and getting worse. Measure that by disposable income growth, economic outlook, unemployment rate, direction of the unemployment rate, or however you like but it doesn't change the fundamental truth that leaders have to appear to be delivering on the fundamentals or they get replaced. This article is to electoral analysis as sweet tarts are to dental hygiene.

  • m913 on October 25, 2011 9:19 AM:

    The essential truth of an election is that it is a choice. While it is true that re-elections reflect some choice of "this one again or not", mostly it is a choice of "this one or that one". So one cannot intelligently analyze any election until both nominees are known.

    Let us wait until we know the identity of the Republican opponent before we analyze whether Obama can defeat him (her).

  • nancy on October 25, 2011 4:31 PM:

    Keith you are really crazy...