in Probability edited ago by
6 votes
6 votes

If the pdf of a Poisson distribution is given by $f(x) = \dfrac{e^{-2} 2^x}{x!}$ then its mean is

  1. $2^x$
  2. $2$
  3. $-2$
  4. $1$
in Probability edited ago by

1 Answer

9 votes
9 votes
Best answer
If we let X = The number of events in a given interval,
Then, if the mean number of events per interval is 
The probability of observing x events in a given interval is given by

Poisson Distribution function $P\left ( X=x \right ) =\frac{e^{-\lambda }\lambda ^{x}}{x!}$

Given Distribution function $f\left ( x \right )=\frac{e^{-2 }2 ^{x}}{x!}$

Comparing both the function

SO Mean $\left ( \lambda \right )=2$
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