14 STAT promblems for STRONG HEART ONLY

1. The minimum and maximum values of the correlation coefficient r are, respectively,

A. −1 and 0
B. −1 and 1
C. 0 and +∞
D. 0 and 1

2. In the left column below are listed the r-values of various data sets, each of which contains 100 points. Descriptions of those data sets are shown in the right column. Match each r-value with the description of the data set with which it is most likely associated.

5. The table below shows a measure of the “liberalness” of various American cities and a measure of the corresponding asking price per square foot for housing.

Enter the slope and y-intercept of the regression line, using liberalness as the independent variable. Round your answers to two decimal places.

Slope:        Intercept:

Enter the correlation coefficient and the coefficient of determination for the data. Round your answers to two decimal places.

Correlation coefficient:     Coefficient of determination:

6. The table below shows the ages and bone densities for five women.

7. The table below shows the ages and bone densities for five women.

8. The table below shows a firm’s advertising budget, in thousands of dollars, and its sales, also in thousands of dollars, for one year.

Find the correlation coefficient to two decimal places:

Which of the following is the equation of the regression line?

A. y=14.833x−22.998
B. y=14.833x+22.998
C. y=22.998x+14.833
D. y=−14.833x+22.998
E. y=22.998x−14.833
F. y=−14.833x−22.998

9. The following data represent a random sample of earwig density (x) and the proportion of males that have forceps (y).

Which of the following is the correlation coefficient?

A. 0.15
B. 0.35
C. 0.02
D. 1

Which of the following is the equation of the regression line?

A. y^=0.1235x+0.3514
B. y^=0.3514+0.1235x
C. y^=0.0072+0.1622x
D. y^=0.0072x+0.1622

10. The following scatter plot represents the lung capacity of children (y) as compared to the height of those children (x).

Click image to enlarge

The correlation coefficient for the data is r=0.84. Is it appropriate to use a linear model to make predictions?

A. Yes
B. No

Assuming that it is correct to do linear regression on the data, use the linear model of the data, y^=−82.1+1.05x, to predict the lung capacity for a child whose height is 150 cm.

A. 75.4 ml
B. 162.74 ml
C. 154.5 ml
D. 90.64 ml

11. The following scatter plot shows the number of wolf pups that survive winter vs. the inbreeding coefficient.

The correlation coefficient is −0.61 for this data. Is it appropriate to use a linear model to make predictions?

A. No
B. Yes

Assuming that it is correct to do regression on this data, use the linear model of this data, 6.59−11.45x, to predict how many pups will survive winter if the inbreeding coefficient is 0.23. (Obviously, you should round to the nearest integer here!)

12. The following scatter plot shows the number of wolf pups that survive winter vs. the inbreeding coefficient.

The correlation coefficient is −0.61 for this data. Is it appropriate to use a linear model to make predictions?

A. No
B. Yes

Assuming that it is correct to do regression on this data, use the linear model of this data, 6.59−11.45x, to predict how many pups will survive winter if the inbreeding coefficient is 0.23. (Obviously, you should round to the nearest integer here!)

13. Which of the following could be a value of the coefficient of determination r2?

A. −1.0994
B. −0.114
C. 0.0589
D. 1.122

14.The table below shows the total SAT scores and IQs of several students.

First, find the coefficients of the regression line, using IQ as the independent variable. Round your answers to three decimal places.

Next, use the equation of the regression line to estimate the SAT score of a student whose IQ is 100. Round your answer to the nearest whole integer.

Finally, give the correlation coefficient, rounded to three decimal places.