STATISTICS
(COMMON DISTRIBUTIONS)
Frequency distributions show the frequency of each
outcome in a given situation. There are several types
of common distributions.
NORMAL DISTRIBUTION
 In a normal distribution, the data
are distributed symmetrically about
the mean (bell–shaped). The
mean, median, and mode are close
in value and are located at the
centre of the distribution.
Ex.
SKEWED DISTRIBUTION
 A non–symmetrical (or lopsided)
distribution of data. A skewed
distribution has the appearance of
a normal distribution that has been
pushed to one side of the mean.
The data can be clustered on the
right or left side of the mean (right
skewed or left skewed).
Ex.
BIMODAL DISTRIBUTION
 A distribution that contains two
equally likely measures of central
tendency (two modes) within the
data and is symmetrical about both
the centres.
Ex.
Unit 8 Lesson 6
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Example 1:
In each case, predict the shape of the data distribution.
a)
the heights of the members of the Toronto Raptors basketball team
b)
the cost of 1L of gas in a city in Ontario
c)
the masses of players on the Canadian Olympic men’s and women’s
hockey teams
Homework:
p.153–155 #1–7
Unit 8 Lesson 6
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