udhyper function

UNU.RAN object for Hypergeometric distribution

Create UNU.RAN object for a Hypergeometric distribution with parameters m, n, and k.

[Distribution] -- Hypergeometric.

udhyper(m, n, k, lb=max(0,k-n), ub=min(k,m))

Arguments

• m: the number of white balls in the urn.
• n: the number of black balls in the urn.
• k: the number of balls drawn from the urn.
• lb: lower bound of (truncated) distribution.
• ub: upper bound of (truncated) distribution.

Details

The Hypergeometric distribution is used for sampling without

replacement. The density of this distribution with parameters m, n and k (named $Np$, $N-Np$, and $n$, respectively in the reference below) is given by

for $x = 0, \ldots, k$.

The domain of the distribution can be truncated to the interval (lb,ub).

Returns

An object of class "unuran.discr".

References

N.L. Johnson, S. Kotz, and A.W. Kemp (1992): Univariate Discrete Distributions. 2nd edition, John Wiley & Sons, Inc., New York. Chap. 6, p. 237.

Author(s)

Josef Leydold and Wolfgang H"ormann unuran@statmath.wu.ac.at .

Examples

## Create distribution object for Hypergeometric distribution
dist <- udhyper(m=15,n=5,k=7)
## Generate generator object; use method DGT (inversion)
gen <- dgtd.new(dist)
## Draw a sample of size 100
x <- ur(gen,100)