His conclusion:

“There is a broader point. Some people are now doubting not only the prediction markets but also the polls, saying that no one knows anything, and that anything is as likely as anything else. Don’t believe it. To be sure, we are continuing to obtain information about how prediction markets perform and when they do well and poorly. Perhaps they will turn out to be less reliable than they seem — and in all likelihood, we will obtain a better understanding of when they work. And of course no one has a crystal ball. But the polls are generally pretty good — and if you want to have a sense of the probabilities, you’d probably do best to consult Intrade.”