The Harvard-affiliated historian writes:

It’s a paradox. The economy is in the doldrums. Yet the incumbent is ahead in the polls. According to a huge body of research by political scientists, this is not supposed to happen. On the other side of the Atlantic, it hardly ever does. But in America today, the law of political gravity has been suspended.

Data (from Doug Hibbs):

Take a look at 2% growth on the above chart. Then get back to me. Sometimes the incumbent party won with 2% growth, other times they lost. It’s “hardly a law of political gravity” that the incumbent will lose.

To be fair, Doug Hibbs recently wrote that his model gives Obama a forecast vote share of 47%. Hibbs also writes that his standard error is 2.2%, so an Obama win is hardly out of the question “even if my [Hibbs’s] guess of a 1-2 percent average per capita real income growth over the last 4 months of the term turns out to be accurate . . .”

So I see no basis for Ferguson’s claim that “according to a huge body of research by political scientists, this is not supposed to happen.” A more accurate statement is that voters appear to respond to recent changes in the economy (hence Obama not being hurt by the full four years of recession), 2% growth is not historically so bad, and, sure, maybe some of the discrepancy between model and polls is coming from the campaign and personal characteristics.

But to say “it’s about personal likability” . . . no way. This is the same sort of self-deluded excuse that liberals were giving when Ronald Reagan was winning elections, and it doesn’t look any better when it’s coming from a conservative.

Romney may yet win. If he loses, I recommend to Ferguson move to the reasonable backup position that Obama got lucky on the timing of the economy. That’s gonna make Ferguson look a lot less

Memo to Newsweek: Since you’re running columns about political science, I suggest you ask my colleague Robert Erikson to write for you. He knows a lot, and I think he won’t embarrass you.

P.S. Just for a change of pace, I have no reason to think Ferguson is being a hack in this case. I’m guessing it’s just a combination of four factors:

1. He doesn’t know the literature.

2. He’s so convinced that Obama is a disaster that he can’t understand why anyone would vote for him (recall Ferguson’s earlier claim, reminiscent of Thomas Frank, that “If young Americans knew what was good for them, they would all be in the Tea Party.”).

3. He’s overconfident: once something comes to his mind, he doesn’t check it.

4. Nobody knowledgeable is editing his column.

I think there’s enough in 1-4 above to explain Ferguson’s error, without recourse to the “he’s just a hack” explanation.

P.P.S. No, Ferguson doesn’t really deserve all this attention. But this is a political science blog, and Ferguson did refer to “a huge body of research by political scientists.” I guess we should just be glad that this time it’s a historian (rather than, say, an economist or a physicist) getting confused about political science.

[Cross-posted at The Monkey Cage]

Andrew Gelman

Andrew Gelman is a professor of statistics and political science and director of the Applied Statistics Center at Columbia University.