12.2 The Regression Equation
Fitting a least-squares line to a scatter plot, measuring residuals from it, and interpreting the correlation coefficient and the coefficient of determination.
8 exercises
12.2 Exercise 1
SCUBA divers have maximum dive times they cannot exceed when going to different depths. The data in the table show different depths in feet, with the maximum dive times in minutes. Use your calculator to find the least squares regression line and predict the maximum dive time for 110 feet.
12.2 Exercise 2
Table 12.16 below represents the relationship between the number of hours spent studying and final exam grades.
Fill in the following chart as a first step in finding the line of best fit, using the median–median approach.
12.2 Exercise 4
Use regression to find the equation for the line of best fit.
12.2 Exercise 6
What is the slope of the line of best fit? What does it represent?
12.2 Exercise 8
What does an r value of zero mean?
12.2 Exercise 10
When n = 100 and r = –0.89, is there a significant correlation? Explain.
12.2 Exercise 12
Explain what it means when a correlation has an r2 value of .72.
12.2 Exercise 14
The table below represents the relationship between SAT scores on the math portion of the test and high school grade point averages (GPAs).
Use the median-median line approach to find the equation for the line of best fit.
Adapted from Statistics © 2022 Rice University. Licensed under CC BY 4.0. Source: Statistics. Imported at revision 7dea80a.