Outlier Effects on Mean and Range
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Objective
I can describe how outliers affect the mean and range of a data set.
Part 1 of 4
Warm-up video
ProfKelley · 10:32
We don't generate video — this one is by ProfKelley on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
The mean uses all of the data in a set, but it is easily influenced by outliers.
- 2
The median is the middle value in a sorted data set, and it is the best measure of central tendency to report when there are outliers.
- 3
The mode is the value that occurs most frequently, but it is not robust because small changes in frequency can easily affect it.
Part 3 of 4
Practice
3 questions
Explain how an outlier affects the mean of a data set.
Why is the median often a better measure of central tendency than the mean when outliers are present in a data set?
Part 4 of 4
Exit ticket
Quick comprehension check
“A data set of test scores includes the following values: 75, 80, 82, 85, 90, 92, 95, and 30. Identify the outlier in this data set. Then, describe how the outlier affects the mean of the data set.”
Sample answer included in the free materials
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