Bayesian: Are we going there? I guess we're going there\. My good Scientist, I mean that if you offered me either side of an even\-money bet on whether Plum committed the murder, I'd bet that he didn't do it\. But if you offered me a gamble that costs \$1 if Professor Plum is innocent and pays out \$5 if he's guilty, I'd cheerfully accept that gamble\. We only ran the 2012 US Presidential Election one time, but that doesn't mean that on November 7th you should've refused a \$10 bet that paid out \$1000 if Obama won\. In general when prediction markets and large liquid betting pools put 60% betting odds on somebody winning the presidency, that outcome tends to happen 60% of the time; they are well\-calibrated for probabilities in that range\. If they were systematically uncalibrated\-\-if in general things happened 80% of the time when prediction markets said 60%\-\-you could use that fact to pump mony out of prediction markets\. And your pumping out that money would adjust the prediction\-market prices until they were well\-calibrated\. If things to which prediction markets assign 70% probability happen around 7 times out of 10, why insist for reasons of ideological purity that the probability statement is meaningless?
"We only ran the 2012 US Presidential Election one time, but that doesn't mean that on November 7th you should've refused a $~$10 bet that paid out $~$1000 if Obama won."
First of all, as non American I do not know what is specific about November 7th. Second, I think that some people may do not even know, that Obama has actually won.