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A comment on TWTR. Parent comment

Re:TWTR by NickM on Thursday November 07, 2013 @01:11PM (#6691136)
Are you suggesting markets are not efficient? In that case, when can we expect you to become extremely wealthy from your inefficiency-proving strategy? (Claiming the EMH is false is equivalent to claiming that such a strategy exists.)

What if I were able to prove that markets are inefficient because efficiently pricing securities is an NP-complete problem? Well, sure, maybe a strategy exists, but if it requires solving an intractable problem then I'm not about to get rich off of my proof ;)

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Re:TWTR by yummyfajitas on Thursday November 07, 2013 @01:29PM (#6691269)
Yes, David Pennock has had these results for a while. The economist would merely argue that results which are computationally intractible are equivalent to information which does not exist. And the computer scientist would point out this doesn't mean markets can't approximate efficient with a high degree of accuracy.
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