You are using the techical description of "efficient markets" right? (i.e. perfectly accurate odds). Of course by this standard you are bound to be correct. However I'm sure you realized that by participating in and 'beating' the market you are increasing its accuracy.

The important question is 'how useful or accurate are these markets compared to anything else?'. I'd challenge you to find a more accurate predictive indicator that is publicly available (even if not for free).

fivethirtyeight.com may have a more reliable method. Time will tell. An aggregate of polls with solid math applied to it might just win by having more data.

Now, if there were a US-legal prediction market, that would be something.

I think it is unlikely that fivethirtyeight.com would be more reliable. The human minds are still more subtle than statistical methods alone. However even if 538 did prove more accurate its results would soon be incorporated into the market by betters. The reverse is not so likely to occur.

> Now, if there were a US-legal prediction market, that would be something.

You would have to think that involving US citizens would improve the market's accuracy. It's ironic that US-citizens can't bet.

They can if they're motivated enough. Intrade is much easier than Betfair.

You think it could be more reliable than following the money?

What about an aggregate of money-based prediction markets?

Actually they do tend to aggregate anyway because of arbitrage.

Yes, the technical description.

Oh man, prediction markets should be used for everything. I love them.

Yeah but politics (at least on Intrade) is much further away than most, and in ways you can predict and exploit.

I have a suspicion the same is true, but to a much lesser extent, of NFL games, but I can't confirm it.

Do to the volume of games and # of teams, NCAA basketball is actually the best for exploiting. The book The Smart Money is a great read.

Also, we have some people in the know post on the TicketStumber blog:

http://ticketstumbler.com/blog/category/sports-insights/

http://sports.ticketstumbler.com/blog/?cat=4

My gambling "fund" is up 35% for the year. My stocks are down by a similar margin.

Interestingly, a friend a couple months ago was telling me about ultra ETFs. They use leverage to ensure (quite reliably so far, though they're new) a daily return of double the index they're based on. He specifically recommended one that is short the S&P.

I haven't talked to him since, but I suspect he's buying a beach house ATM.

Double the loss though right? The banks went under for similar reasons - way too much leverage.

Yeah, over time an ultra etf should make 2x what the s&p gains (and a short one would lose 2x). In the short term though that's a hell of a profit (on the ultra shorts) when things go the way they have.