Mean[ Distribution ]
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg1928] Mean[ Distribution ]
- From: wiener at finance.wharton.upenn.edu (Zvi Wiener)
- Date: Wed, 23 Aug 1995 22:31:10 -0400
- Organization: University of Pennsylvania
Dear Mathematica users:
How can one use Statistics package to find expected value (and higher
moments) for a random variable which distribution is given by a standard
function? Like this: I wish to find expected value of, say E^x, where x
is normally distributed:
In[1]:= <<Statistics`Master`
In[2]:= Mean[ NormalDistribution[0,.1]]
Out[2]= 0
this works OK!
In[3]:= Mean[ E^NormalDistribution[0,.1]]
NormalDistribution[0, 0.1]
Out[3]= Mean[E ]
But here I would like to have different answer
Of course I can do it manually like:
In[4]:= Integrate[ E^x*E^(-x^2/2), {x, -Infinity, Infinity}]
Out[4]= Sqrt[2 E Pi]
But I am sure there is a more straightforward way using the
NormalDistribution distribution. HOW ?
Thank you in advance.
Zvi Wiener.
zwiener at lehman.com