Outliers in a Data Set

A value that is much higher or much lower than the other values in a set of data.

• Outlier

• Box Plot

• Range

• Histogram

When using IQR to find outliers, which formula will identify the upper limit?

• 1.5(IQR)

• Q1 + 1.5(IQR)

• Q1 - 1.5(IQR)

• Q3 + 1.5(IQR)

When using IQR to find outliers, which formula will identify the lower limit?

• 1.5(IQR)

• Q1 + 1.5(IQR)

• Q1 - 1.5(IQR)

• Q3 + 1.5(IQR)

Given the data set below:
15, 56, 58, 60, 63, 75, 80, 80, 85
How does the outlier affect the distribution of the data?

• The outlier skews the distribution to the left.

• The outlier skews the distribution to the right.

• The outlier makes the distribution more symmetrical.

• The outlier has no effect on the distribution.

Find the outlier of the data set.

15, 20, 18, 35, 17, 35, 13

• None

• 35

• 13

• 15

Using the information below, identify which of the following is an outlier:
Q1 = 3
Q2 = 7
Q3 = 12

• 22

• 25.5

• -8.5

• 26

Using the information below, identify which of the following is NOT an outlier:

• 73

• 40

• 80

• 73.5

A data set contains only one outlier. Which statistical measure will most likely remain the same if the outlier is removed?

• Mean

• Mode

• Range

• Standard deviation

Given the following data set
6, 9, 12, 14, 7, 9, 6, 8, 25, 12, 14
What is the mean of the data set without the outlier(s)?

• 9.2

• 9.7

• 11.1

• 12.4

A bowler had the following scores after 5 games:
 196, 205, 197, 280, and 202.
How much does the bowler’s mean score increase if the outlier is considered, compared to if the outlier is not considered?

• 13

• 16

• 19

• 22