Education Technology

# Activities

• ##### Subject Area

• Math: Statistics: Describing Bivariate Data

9-12

40 Minutes

• ##### Device
• TI-Nspire™ CX/CX II
• TI-Nspire™ CX CAS/CX II CAS
• TI-Nspire™ Navigator™
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

5.0

## Does a Correlation Exist?

#### Activity Overview

In this activity, students will determine, by examining a graph, if a data set has a positive or negative correlation coefficient. Then, they will find the linear regression equation and calculate the correlation coefficient. They will use this line to predict the value of y for a given x and vice-versa. Finally, students will investigate the effect of outliers and influential points on the regression equation and correlation coefficient.

#### Objectives

• Students will construct a scatter plot and determine a linear regression that fits the data.
• Students will calculate a correlation coefficient from data sets.
• Students will describe correlation in data sets and distinguish it from causation.

#### Vocabulary

• causation
• correlation coefficient
• linear regression
• outlier