
Bin Laden and Inefficient Markets - chrismealy
http://economix.blogs.nytimes.com/2011/05/02/bin-laden-and-inefficient-markets/
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orangecat
If prediction markets are efficient, an event with a contract trading at 4 out
of 100 _should_ occur 4% of the time. If it never occurred, the contract would
be overpriced. A better test would be to take a bunch of contracts trading at
low values today, and then check in the future to see how many actually
happened.

