This function returns a random integer from the hypergeometric distribution. The probability distribution for hypergeometric random variates is,
where \(C(a,b) = a!/(b!(a-b)!)\) and \(t \leq n_1 + n_2\). The domain of \(k\) is \(\max(0,t-n_2), ..., \min(t,n_1)\).
If a population contains \(n_1\) elements of “type 1” and \(n_2\) elements of “type 2” then the hypergeometric distribution gives the probability of obtaining \(k\) elements of “type 1” in \(t\) samples from the population without replacement.
This function computes the probability \(p(k)\) of obtaining \(k\) from a hypergeometric distribution with parameters n1, n2, t, using the formula given above.
These functions compute the cumulative distribution functions \(P(k), Q(k)\) for the hypergeometric distribution with parameters n1, n2 and t.