Identifying Outliers Using 1.5 Rule

What is an outlier in a data set?

• A data point that is irrelevant to the data set

• A data point that is within the average range of the data set

• A data point that is exactly in the middle of the data set

• A data point that differs significantly from other observations in the same data set.

Answer explanation

An outlier is a data point that differs significantly from other observations in the same data set.

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

The data set below has an outlier of 42.
2, 5, 12, 15, 19, 4, 6, 11, 16, 18, 12, 12, 42
What effect does removing the outlier have on the distribution of the data?

• The mean will decrease

• The median will decrease

• The mean will increase

• The median will increase

What are the coordinates of the outlier?

• (3,4)

• (4,3)

• (3,10)

What are the coordinates of the outlier?

• (9,1)

• (0,3)

• (1,9)

Use the 1.5 IQR rule to determine if there are any outliers for the following numbers:
84, 88, 72, 74, 98, 16, 94

• Yes, 16 is an outlier.

• Yes, 33 is an outlier.

• Yes, 98 is an outlier.

• There are no numbers less than 39 or greater than 124, therefore there are no outliers.

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)

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

• Outlier

• Box Plot

• Range

• Histogram

Which value(s) are outlier(s) for the age of male Oscar winners?

• 80

• 76

• 60

• 29

The salaries of the employees in a company are listed below: $28,000 $45,000 $31,000 $42,000 $55,000 $72,000 $88,000 $53,000 If $88,000 was found to be an outlier, which salary would be the new maximum?

• $55,000

• $28,000

• $88,000

• $72,000