Page 153 - Probability Demystified

142 CHAPTER 8 Other Probability Distributions

5. ¼ 3 and x ¼ 5

x
e ð2:7183Þ 3 3 5
¼ 0:101
x! 5!

Summary

There are many types of discrete probability distributions besides the
binomial distribution. The most common ones are the multinomial distri-
bution, the hypergeometric distribution, the geometric distribution, and the
Poisson distribution.
The multinomial distribution is an extension of the binomial distribution
and is used when there are three or more independent outcomes for a
probability experiment.
The hypergeometric distribution is used when sampling is done without
replacement. The geometric distribution is used to determine the probability
of an outcome occurring on a specific trial. It can also be used to find the
probability of the first occurrence of an outcome.
The Poisson distribution is used when the variable occurs over a period of
time, over a period of area or volume, etc.
In addition there are other discrete probability distributions used in
mathematics; however, these are beyond the scope of this book.

CHAPTER QUIZ

1. Which distribution requires that sampling be done without replace-
ment?

a. Geometric
b. Multinomial
c. Hypergeometric
d. Poisson
2. Which distribution can be used when there are 3 or more outcomes?
a. Geometric
b. Multinomial
c. Hypergeometric
d. Poisson