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Scatterplots, Coefficients, and Regression Analysis

I need help with the attached. It deals with scatter plots.

Thank you for you help.
1. A value of r = -0.851 shows that there is very little relationship between the two variables being compared.

2. A value of r = 0.158 shows that there is very little relationship between the two variables being compared.

3. If a correlation coefficient of r = 0.642 was found between two variables in a sample of paired data that were measured in feet, the value of r would change if the data were converted to inches and r was computed again.

4. Bear Chest Size and Weight. Listed below are the chest sizes (in inches) and weights (in pounds) of randomly selected bears that were anesthetized and measured (based on data from Gary Alt and Minitab, Inc.). Because it is much more difficult to weigh a bear than to measure its chest size, the presence of a correlation could lead to a method for estimating weight based on chest size. Is there a linear correlation between chest size and weight?

5. Buying a TV Audience. The New York Post published the annual salaries (in millions) and the number of viewers (in millions), with results given below for Oprah Winfrey, David Letterman, Jay Leno, Kelsey Grammer, Barbara Walters, Dan Rather, James Gandolfini, and Susan Lucci, respectively. Is there a correlation between salary and number of viewers? Which of the listed stars has the lowest cost per viewer? Highest cost per viewer?

6. Temperatures and marathons. In "The Effects of Temperature on Marathon Runner's Performance," by David Martin and John Buoncristiani (Chance, Vol. 12, No. 4), high temperatures and times (in minutes) were given for women who won the New York City marathon in recent years. Results are listed below. Is there a correlation between temperature and winning time? Does it appear that winning times are affected by temperature?

7. Use the same data sets as Exercises 13-32 in Section 10-2. In each case, find the regression equation, letting the first variable be the independent (x) variable. Find the indicated predicted values.

Bear Chest Size and Weight. Find the best predicted weight (in pounds) of a bear with a chest size of 50 in.


Solution Summary

This is a set of solutions for correlation coefficients, scatter plots, linear correlations, and regression analyses.