You probably know about Intrade, the betting/prediction site that tracks political contests.

Just look at this chart after the jump …

Obviously, Intrade isn’t gospel. It’s the combined ‘wisdom’ of what a bunch of speculators believe is going to happen. My own sense is that — not surprisingly — Intrade does okay on questions where most of the information is public (political races) and not good at all in cases where little of the information is public (ACA ruling before SCOTUS). That makes sense because that’s how an actual stock market is supposed to work.