<>
In this particular case, there is a shortcut to the mean which makes your
life easier. If no such shortcut existed, you would indeed have to calculate
the integral...
HTH
Martin
-----Ursprüngliche Nachricht-----
Von: [email protected]
[mailto:[email protected]] Im Auftrag von carol white
Gesendet: Sonntag, 18. Oktober 2009 20:05
An: [email protected]
Betreff: st: mean of a distribution
Hi,
How to calculate the mean of the distribution of a random variable? Take the
exponential distribution with the probability density function
f(x)=lambda.exp(-lambda.x) where lambda is a constant and x is a random
variable. The mean of this distribution is the reciprocal of lambda. If the
mean is the expected value of x, which for a continuous random variable E(x)
= Integral (x.f(x))dx, how could E(x) be the reciprocal of lambda?
Regards,
Carol
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