How can we describe a set

of data?

Range

Range: The range tells you how spread out the data is.

Tournament

1 2 3 4 5 6 7 8 9 10

Points 9 6 10 9 15 9 12 12 20 13

Carey recorded the number of points she scored in each of 10 volleyball tournaments.

What is the range of data?

How do we find the Range Range: The range tells you how spread out the

data is.

Tournament

1 2 3 4 5 6 7 8 9 10

Points 9 6 10 9 15 9 12 12 20 13

Carey recorded the number of points she scored in each of 10 volleyball tournaments.

Subtract the minimum, the least number, from the maximum, the greatest number, in the set of data.20 – 6 = 14

How do we find the Mean?

The mean is also called the average.

Tournament

1 2 3 4 5 6 7 8 9 10

Points 9 6 10 9 15 9 12 12 20 13

If the mean is 11.5, how do you find the mean?

Add all the data and divide the sum by the number of data values in the set.

9 + 6 + 10 + 9 + 15 + 9 + 12 + 12 + 20 + 13 = 115115 / 10 = 11.5

How do you find the median?

If the median of this set of data is 11, how did I find it?

Tournament

1 2 3 4 5 6 7 8 9 10

Points 9 6 10 9 15 9 12 12 20 13

Arrange the data in order. If there are an odd number of data values, select the middle number. If there are an even number of data values, find the mean of the two middle numbers.

6 9 9 9 10 12 12 13 15 20 10 + 12 = 22 22/2 = 11

How do I find the mode?

If the mode is 9, how did I figure it out?

Tournament

1 2 3 4 5 6 7 8 9 10

Points 9 6 10 9 15 9 12 12 20 13

Choose the number that occurs most often. Sometimes there is no mode, and sometimes there is more than one mode.

6 9 9 9 10 12 12 13 15 20

Outlier: how would you define it?

Outliers

A number very different from the other numbers in a data set

What’s the outlier?