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Chapter 9: The Normal Probability Distribution
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CHAPTER 9
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The Normal Probability Distribution
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You should study the topics in this chapter if you need to review
or want to learn about
The normal probability distribution
The standard normal probability distribution
z
scores
Probability associated with any normal probability distribution
The normal approximation to the binomial distribution
9 - 1 Introduction
Here we will focus on a special continuous random variable that can assume
any value in the interval (-
, +
). That is, the random variable can assume
any value on the real number line. The distribution for this continuous
random variable is called the normal distribution and was originally called
the Gaussian distribution in honor of Karl Gauss, who in 1833 published a
work describing it. This probability distribution may be considered as the
most important probability distribution in all of statistics.
The following data set summarizes the chest sizes of Scottish militiamen in
the early 19
th
century. Chest sizes are measured in inches, and each
observation reports the number of soldiers with that chest size.
Source
:
http://lib.stat.cmu.edu/DASL/Datafiles/MilitiamenChests.html