sigma2_cnb: Variance of Conditional Negative Binomial
Description
Function calculating variance of the conditional distribution of X given X + Y = D,
where X ~ NB(r1, p1) and Y ~ NB(r2, p2) are drawn from two negative binomials,
independent of each other,
and assuming p1/p2 = lambda.
Usage
sigma2_cnb(D, r1, r2, lambda)
Arguments
D
a positive integer.
r1
a positive value.
r2
a positive value.
lambda
a positive value.
Value
V(X | X + Y = D).
Details
Need to specify full list of arguments, as default values have not been set.