Paul Krugman has a new book coming out, which means he is doing a lot of thing that one doesn't normally see from a Nobel Prize-winning economist. First he debated Ron Paul on Bloomberg TV, including a bizarre interlude involving inflation in third-century Rome. Then yesterday, he did a question and answer session with Reddit, the hugely popular social news site which brands itself "The Front Page of the Internet".
Under the headline IamA Nobel Prize-winning economist and New York Times columnist, Krugman – username nytimeskrugman – spent a couple of hours answering questions from Reddit users. Here are some of his best answers.
Well, not being able to do experiments is a problem, but not as bad as all that. We do have statistical techniques for trying to sort out what's going on, although I'm skeptical about their power. But mainly we can look for "natural experiments", which often tell you a lot. In End This Depression I talk about how wars provide a natural experiment on fiscal policy; right now forced austerity in Europe is providing another set of natural experiments.
You may ask whether both sides in every debate won't nonetheless find ways to support their positions. My answer here is that this is not, in fact, happening. On the question of whether austerity is expansionary or contractionary, we had some alleged evidence for expansionary effects, but it was quickly shot down by the normal process of scholarly discussion. In any normal scientific debate, this would now be a settled issue.
I guess that what I'm saying here is that while the non-experimental nature of economics is an issue, the apparent inability to resolve differences that you see right now is about politics, not the inherent problems of the discipline.
All around Europe's periphery they're doing it as we speak, er, type. The euro has served as the functional equivalent of the gold standard.
The difference for, say, Spain is that since they don't have their own currency, it's much harder to change course than it would have been for Britain under gold. But if you look at, say, Latvia, they're doing the full Churchill -- and being hailed as a role model even as they enforce a devastating slump on themselves.
I think it is to point out that if nobody is buying, nobody can sell. Austerity in a depressed economy makes the depression deeper, and that is, I believe, a point people can grasp. Of course, it's a point made easier to grasp now that the Irish and others have given us such clear examples of how bad the results of austerity can be.
I think there's a lot of very good work in behavioral econ. But I don't expect a unified theory for many, many years. There are just two many ways the assumption of perfect rationality can fail, and I don't think we have enough broader understanding to put it all in one package.
That said, we can use behavioral econ even as it is, as long as we're modest about modeling. As long as we are prepared to say "this is how people actually seem to behave" without demanding general theorems -- for example the obvious reluctance to accept nominal wage cuts -- we can go a long way toward analyzing real-world issue in a way that can guide both prediction and policy.
Finally, one of Krugman's answers which works best without any context:
Shave around it every day, and get your wife to clip it fairly often.
(Oh all right, he was talking about his beard)