Precalculus: Two Models are Better than One

Objectives

• Students will determine and analyze an exponential model for the data involving carbon dioxide in the atmosphere.
• Students will develop an improved model for this data by using the residuals associated with the exponential regression function.

Vocabulary

• regression equation
• residual
• residual plot
• SSE = sum of the squares of the residuals (errors)

About the Lesson

This lesson involves modeling the amount of carbon dioxide in the air over a 12-month period.
As a result, students will:

• Analyze the shortcomings of an exponential regression function fitting the given data.
• Find an improved model by adding the original exponential function to one fitting the data in the residual plot of the original function.