num_drawn

Distribution parameter for the hypergeometric distribution describing the number of draws from a combined population

Specification

• Alias: None

• Arguments: INTEGERLIST

Description

The density function for the hypergeometric distribution is given by:

$$\begin{array}{r}f(x)=\frac{\left(\begin{array}{c}m\\ x\end{array}\right)\left(\begin{array}{c}N-m\\ n-x\end{array}\right)}{\left(\begin{array}{c}N\\ n\end{array}\right)}\end{array}$$

where the three distribution parameters are:

• N is the total population

• m is the number of items in the selected population (e.g. the number of white balls in the full urn of N items)

• n is the size of the sample drawn (e.g. number of balls drawn)

In addition,

• x, the abscissa of the density function, indicates the number of successes (e.g. drawing a white ball)

• $\left(\begin{array}{c}a\\ b\end{array}\right)$ indicates a binomial coefficient (“a choose b”)