hello i was wondering if anyone could help me with this problem
the problem says: The relationship between incomplete gamma intergrals and sums of Poisson probabilities is given by
1/ gamma(alpha) intergral from lambda to infinity y^(alpha - 1) e^-lamdba dx =
sum from y=1 to alpha -1 (lambda^y e^-lamba)/y!
for integer values of alpha. If Y has a gamma distribution with alpha = 2 and
beta =1. find P(Y>1)
i used the general forumal for gamma distributions and got
p(Y>1) = intergral from 1 to infinity y^1 e^-y dy =
-ye^-y evaluated from 1 to infinity - intergral from 1 to infinity -e^-y dy=
0 + e^-1 -(0 - e^-1) = 2e^-1
i don't understand what the forumlas that were in given in the problem are used for
the problem says: The relationship between incomplete gamma intergrals and sums of Poisson probabilities is given by
1/ gamma(alpha) intergral from lambda to infinity y^(alpha - 1) e^-lamdba dx =
sum from y=1 to alpha -1 (lambda^y e^-lamba)/y!
for integer values of alpha. If Y has a gamma distribution with alpha = 2 and
beta =1. find P(Y>1)
i used the general forumal for gamma distributions and got
p(Y>1) = intergral from 1 to infinity y^1 e^-y dy =
-ye^-y evaluated from 1 to infinity - intergral from 1 to infinity -e^-y dy=
0 + e^-1 -(0 - e^-1) = 2e^-1
i don't understand what the forumlas that were in given in the problem are used for