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Chapter 8: Discrete Probability Distributions
Figure 8-25:
Display of the experimental design for the
Hypergeometric Distribution
If we let
X
= number of successes in a hypergeometric experiment, then
X
is
called a hypergeometric random variable. The probability distribution for
the hypergeometric random variable is the hypergeometric distribution.
Figure 8-26
will help us see the logic of the hypergeometric experiment and
it will help us to derive the functional form for the hypergeometric
distribution.
From
Figure 8-26
, the number of ways of selecting
x
successes from
successes will be
. The number of ways of selecting
n
–
x
failures from
–
failures will be
. Thus the total number of ways of selecting the
x
successes and the
–
failures will be
(using the multiplication
rule for counting).