Education Technology

# Activities

• ##### Subject Area

• Math: Statistics: Inferential Statistics

9-12

60 Minutes

• ##### Device
• TI-89 / TI-89 Titanium

TI Connect™

• ##### Accessories

TI Connectivity Cable

• ##### Other Materials
This is Activity 4 from the EXPLORATIONS Book:
Advanced Placement Statistics with the TI-89

## Exploring Bivariate Data

#### Activity Overview

Students graph scatter plots and understand the concepts of correlation and least-squares regression. They also perform transformations to achieve linearity in the data plot.

#### Before the Activity

Install the Statistics with List Editor application on the calculator using one of these two methods:

• TI Connect™, a TI Connectivity Cable, and the Unit-to-Unit Link Cable
• TI-Navigator™ "send to class" feature
• See the attached PDF file for detailed instructions for this activity
• Print pages 59 - 78 from the attached PDF file for your class

#### During the Activity

Distribute the pages to the class.

• Enter the heights of buildings in Philadelphia & New York City, and the year of their completion, as lists
• Set up scatter plots for both sets and compare the graphs
• Enter the car name, mileage per gallon, weight of car, and number of cylinders as lists
• Find the simple linear correlation coefficient between mileage and weight, mileage and cylinder, cylinder and weight
• Plot the data and observe the relationship
• Plot a least-squares regression line through the data
• Observe that the line does not fit the data sufficiently
• Identify the outliers
• Plot the data without the outlier point and observe that the line is close to the regression line
• Calculate the Coefficient of Determination and the sum of squares regression and linearize the data
• Perform different types of transformations and measure how well the line fits the transformed data
• #### After the Activity

Review student results:

• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary