problem with ExpectedValue[xx-x, PoissonDistribution[m],x]

*To*: mathgroup at smc.vnet.net*Subject*: [mg50126] problem with ExpectedValue[xx-x, PoissonDistribution[m],x]*From*: W Randolph Franklin <math at wrfranklinNOSPAM.org>*Date*: Mon, 16 Aug 2004 06:45:32 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

(This is a repeat of my posting of Aug 5, since there were no replies, and I am still interested in the answer.) Why can Mathematica not evaluate ExpectedValue[x x - x, PoissonDistribution[m], x] ? It can correctly evaluate all the following: ExpectedValue[x x , PoissonDistribution[m], x] ExpectedValue[x , PoissonDistribution[m], x] ExpectedValue[x x + x , PoissonDistribution[m], x] ExpectedValue[x x + a x , PoissonDistribution[m], x] Is it anticipating to think that I've found a Mathematica bug, in my first hour of using Mathematica? (If so, that's rather good for me and new SW packages). Thanks. remove the NOSPAM to reply