Write the correct answer in the blanks below and include your output with this page when you turn it in. Problem 1A traffic safety officer conducted an experiment to determine whether there is a corr



Write the correct answer in the blanks below and include your output with this page when you turn it in.


Problem 1

A traffic safety officer conducted an experiment to determine whether there is a correlation between people's ages and driving speeds. Six individuals were randomly sampled and the following data were collected. Compute a pearson r and then construct a least squares regression equation using age to predict driving speed.


Age

20

25

45

46

60

65

Speed (mph)

60

47

55

38

45

35




(1)What is Peason r _____________________


(2) What type of data is need to compute Parson r? ________________ Or _______________


  1. What is the least squares regression equation for using age to predict driving speed.



  1. What percent of the variance in driving speed can we account for by knowledge of age?


(1)What is the slope of the regression line?

  1. Is the slope significantly different from 0?(how do you know?)________________


(2) For each unit change age what happens to driving speed? ______________________________


  1. What number reflects the error in prediction? ______________________________


  1. What assumption must you satisfy to allow you to correctly interpret the measure of error in prediction?___________



Problem 2

A researcher collects data on the relationship between the amount of daily exercise an individual gets and the percent body fat of the individual. The following scores are recorded.


Individual

1

2

3

4

5

Exercise (min)

10

18

26

33

44

% Fat

30

25

18

17

14



Compute a pearson r and then construct a least squares regression equation using exercise in minutes to predict % body fat..



  1. What is Peason r



  1. What is the least squares regression equation for using exercise to predict % body fat?


  1. What percent of the variance in percent body fat can we account for by exercise time in minutes?


(1)What is the slope of the regression line?

  1. Is the slope significantly different from 0?(how do you know?)________________



  1. What number reflects the error in prediction


(2) For each unit change in exercise time what happens to body fat? ______________________________