Part 1: Understanding the basics

A random sample of college students was surveyed about how they spend their time each week. The scatterplot below displays the relationship between the number of hours each student typically works per week at a part- or full-time job and the number of hours of television each student typically watches per week. The correlation between these variables is r = -0.63, and the equation we would use to predict hours spent watching TV based on hours spent working is as follows:

Predicted hours spent watching TV = 17.21 - 0.23(hours spent working)

25 20 15 Hours spent watching TV per week 10 .. 5 0- 0 10 20 30 40 50 Hours spent working per week