Outlier Lesson

Outliers: Watch the following video, then continue on with the lessson.

https://youtu.be/9aDHbRb4Bf8

​Effect of Outliers:

• Outliers skew the mean

• If the outlier is high, it makes the mean higher, low it makes the mean lower.

• Median is a better representation in the presence of outliers

​Numbers OUTSIDE the fence are OUTLIERS

Multiple Choice

What measure of center is most greatly effected by outliers?

• Mean

• Median

• Mode

• Range

Multiple Choice

What measure of spread is most greatly effected by outliers?

• Median

• Mean Absolute Deviation

• Range

• Interquartile Range

Multiple Choice

In the data set: 1,2,3,4,2,3,6,15

The number 15 is an outlier. What would happen to the mean if you removed the outlier.

• It would stay the same

• It would increase

• It would decrease

• IDK

Multiple Choice

In the following data set:

200,250,276,300,400,325

Identify the outlier(s)

• There are no outliers

• The outlier is 400

• The outlier is 200

• The outliers are 200 and 400.

Fill in the Blanks

According to the box plot the middle 50% of the data lies between ____ and____

Fill in the Blanks

According to the boxplot what is the median of the data set?

Fill in the Blanks

According to the boxplot what is the range of the lower 50% of the data?

Multiple Choice

Which measurement would change the most if you remove an outlier from a data set?

• Mean

• Median

• IQR

• Mode

Multiple Choice

In the following data set identify the outlier:

1,2,3,4,5,2,3,4,5,9,12

• There is no outlier

• The outlier is 9

• The outlier is 12

• There are two outliers, 9 and 12.