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A comment on Nassim Taleb: We should retire the notion of standard deviation. Parent comment

Re:Nassim Taleb: We should retire the notion of standard dev... by CamperBob2 on Wednesday January 15, 2014 @02:52PM (#7065695) 

   A stock (or a fund) has an average return of 0%. It moves 
   on average 1% a day in absolute value; the average up move 
   is 1% and the average down move is 1%.
How does that yield an average return of 0%?
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Re:Nassim Taleb: We should retire the notion of standard dev... by baking on Wednesday January 15, 2014 @08:00PM (#7067367)
The usual way to do this is to take the natural log, so an up 1% day followed by a down 1% day (or vice versa) will always net out to a 0% change.
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Re:Nassim Taleb: We should retire the notion of standard dev... by MaysonL on Wednesday January 15, 2014 @03:35PM (#7065963)
It goes up a little more often than it goes down?
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