Outlier Effects on Mean and Range

8th GradeMath20 min

aligned to Ccss 8.sp.a.1

Learning Objective

I can describe how outliers affect the mean and range of a data set.

Lesson Flow

Watch Video

11 min

What to Report When There is an Outlier - Measures of Central Tendency

ProfKelley

Guided Notes

5 min

Key concepts students will learn:

  • The mean uses all of the data in a set, but it is easily influenced by outliers.

  • 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.

  • The mode is the value that occurs most frequently, but it is not robust because small changes in frequency can easily affect it.

Practice

10 min

3 questions • Multiple choice & Short answer

Exit Ticket

5 min

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.

Teacher Guide

Get the complete package:

  • Answer keys for all questions
  • Differentiation strategies
  • Extension activities
  • Printable student handouts