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Old 03-18-2007, 01:58 AM
PairTheBoard PairTheBoard is offline
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Join Date: Dec 2003
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Default Re: Interesting Mathematical Paradox?

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Do you then want to switch? The answer I arrived at is, yes, you do want to switch envelopes every time! I currently have $20. The other envelope muse have either twice as much or half as much- in other words, it must have either $40 or $10, ...


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Yes. However you Don't know that the probability is 50% for the $40 and 50% for the $10. Therefore you cannot draw the conclusion,

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... so your EV by switching is $25 ($50 / 2).


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Just because there are two possibilties doesn't make them equally likely.

PairTheBoard
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