# Activities

• • • ##### Subject Area

• Math: Statistics: Describing Bivariate Data

• ##### Author 9-12

50 Minutes

• ##### Device
• TI-Nspire™
• TI-Nspire™ CAS
• TI-Nspire™ CX/CX II
• TI-Nspire™ CX CAS/CX II CAS
• TI-Nspire™ Navigator™
• TI-Nspire™ Apps for iPad®
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

3.6

• ##### Report an Issue

Scatterplot Pulse Rates

#### Activity Overview

This lesson involves creating a scatterplot and fitting a line to student pulse rates collected before and after exercise.

#### Objectives

• Students will analyze the relationship between two quantities by plotting data on a scatterplot.
• Students will informally assess the fit of a function by plotting and analyzing residuals.
• Students will recognize that, if a linear model is a good fit for the data, the residual plot should not have a pattern or be systematic in any way.
• Students will analyze and interpret the significance of the slope and y-intercept of a linear model.

#### Vocabulary

• explanatory variable
• least-squares regression line
• residual
• response variable
• scatter plot
• slope

#### About the Lesson

This lesson involves creating a scatterplot and fitting a line to student pulse rates collected before and after exercise.

As a result, students will:

• Fit a moveable line to a scatterplot of pulse rates before and after exercise.
• Identify large residuals from the scatterplot and line and from the residual plot.
• Drag the line, and observe how the residuals change.
• Inspect the least-squares regression line and the corresponding residual plot.