2) A line has equation 0.5.

Pick five distinct x-values, use the equation to compute the corresponding y-values, and plot the five points obtained.

Give the value of the slope of the line; give the value of the y-intercept.

4) A line has equation y=1.5x+1.

Pick five distinct x-values, use the equation to compute the corresponding y-values, and plot the five points obtained.

Give the value of the slope of the line; give the value of the y-intercept.

8) A data set consists of ten (x,y) pairs of numbers:

(3,20) (5,13) (6,9) (8,4) (11,0) (12,0) (14,1) (17,6) (18,9) (20,16)

Plot the data in a scatter diagram.

Based on the plot, explain whether the relationship between x and y appears to be deterministic or to involve randomness.

Based on the plot, explain whether the relationship between x and y appears to be linear or not linear.

12) The rate for renting a motor scooter for one day at a beach resort area is $25 plus 30 cents for each mile the scooter is driven. The total cost y in dollars for renting a scooter and driving it x miles is

.30x+25

Explain whether the relationship between the cost y of renting the scooter for a day and the distance x that the scooter is driven that day is deterministic or contains an element of randomness.

A person intends to rent a scooter one day for a trip to an attraction 17 miles away. Assuming that the total distance the scooter is driven is 34 miles, predict the cost of the rental.

14) The cost of a telephone call made through a leased line service is 2.5 cents per minute.

Write down the linear equation that relates the cost y (in cents) of a call to its length x.

Calculate the cost of a call that lasts 23 minutes.

16) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs). Plot the scatter diagram with golf score using the original clubs as the independent variable (x) and golf score using the new clubs as the dependent variable (y). Comment on the appearance and strength of any linear trend.

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Section 2

2) For the sample data

xy0023336498

Draw the scatter plot.

Based on the scatter plot, predict the sign of the linear correlation coefficient. Explain your answer.

Compute the linear correlation coefficient and compare its sign to your answer to part (b).

4) For the sample data

xy1525467390

Draw the scatter plot.

Based on the scatter plot, predict the sign of the linear correlation coefficient. Explain your answer.

Compute the linear correlation coefficient and compare its sign to your answer to part (b).

8) Compute the linear correlation coefficient for the sample data summarized by the following information:

x12

12) The curb weight x in hundreds of pounds and braking distance y in feet, at 50 miles per hour on dry pavement, were measured for five vehicles, with the results shown in the table.

xy2510527.512532.51403514045150

Compute the linear correlation coefficient for these sample data and interpret its meaning in the context of the problem.

14) The wind speed x in miles per hour and wave height y in feet were measured under various conditions on an enclosed deep water sea, with the results shown in the table,

xy02.000.020.370.773.3

xy94.9134.9203.0226.9315.9

Compute the linear correlation coefficient for these sample data and interpret its meaning in the context of the problem.

30) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs). Compute the linear correlation coefficient r. Compare its value to your comments on the appearance and strength of any linear trend in the scatter diagram that you constructed in the second large data set problem for Chapter 10, Section 1 "Linear Relationships Between Variables".

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Section 4

2) Compute the least squares regression line for the data in Exercise 2 of Chapter 10, Section 2 "The Linear Correlation Coefficient".

4) Compute the least squares regression line for the data in Exercise 4 of Chapter 10, Section 2 "The Linear Correlation Coefficient".

6) For the data in Exercise 6 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Compute the least squares regression line.

Compute the sum of the squared errors SSE using the definition (yy)2.

Compute the sum of the squared errors SSE using the formula 1SSxy.

18) For the data in Exercise 18 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Compute the least squares regression line.

Compute SSE using the formula 1SSxy.

Estimate the number of acres that would be harvested if 90 million acres of corn were planted.

26) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs).

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Compute the least squares regression line with scores using the original clubs as the independent variable (x) and scores using the new clubs as the dependent variable (y).

Interpret the meaning of the slope 1 of regression line in the context of problem.

Compute SSE, the measure of the goodness of fit of the regression line to the sample data.

Estimate the score with the new clubs of a golfer whose score with the old clubs is 73.

Section 5

2) Construct the 90% confidence interval for the slope 1 of the population regression line based on the sample data set of Exercise 2 of Chapter 10, Section 2 "The Linear Correlation Coefficient".

4) Construct the 99% confidence interval for the slope 1 of the population regression Exercise 4 of Chapter 10, Section 2 "The Linear Correlation Coefficient".

8) Construct the 95% confidence interval for the slope 1 of the population regression line based on the sample data set of Exercise 8 of Chapter 10, Section 2 "The Linear Correlation Coefficient".

12) For the data in Exercise 12 of Chapter 10, Section 2 "The Linear Correlation Coefficient" construct a 90% confidence interval for the mean increased braking distance for each additional 100 pounds of vehicle weight.

14) For the data in Exercise 14 of Chapter 10, Section 2 "The Linear Correlation Coefficient" test, at the 10% level of significance, whether wind speed is useful for predicting wave height.

18) For the situation described in Exercise 18 of Chapter 10, Section 2 "The Linear Correlation Coefficient", an agronomist claims that each additional million acres planted results in more than 750,000 additional acres harvested. Test this claim at the 1% level of significance.

24) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs).

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Compute the 95% confidence interval for the slope 1 of the population regression line with scores using the original clubs as the independent variable (x) and scores using the new clubs as the dependent variable (y).

Test, at the 10% level of significance, the hypothesis that the slope of the population regression line is different from 1, against the null hypothesis that it is exactly 1.

Section 6

2) For the sample data set of Exercise 2 of Chapter 10, Section 2 "The Linear Correlation Coefficient" find the coefficient of determination using the formula r2=1SSxy/SSyy. Confirm your answer by squaring r as computed in that exercise.

4) For the sample data set of Exercise 4 of Chapter 10, Section 2 "The Linear Correlation Coefficient" find the coefficient of determination using the formula r2=1SSxy/SSyy. Confirm your answer by squaring r as computed in that exercise.

12) For the data in Exercise 12 of Chapter 10, Section 2 "The Linear Correlation Coefficient" compute the coefficient of determination and interpret its value in the context of vehicle weight and braking distance.

14) For the data in Exercise 14 of Chapter 10, Section 2 "The Linear Correlation Coefficient" compute the coefficient of determination and interpret its value in the context of wind speed and wave height. Does wind speed seem to be a very important factor with regard to wave height?

18) For the data in Exercise 18 of Chapter 10, Section 2 "The Linear Correlation Coefficient" compute the coefficient of determination and interpret its value in the context of acres planted and acres harvested.

24) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs). Compute the coefficient of determination and interpret its value in the context of golf scores with the two kinds of golf clubs.

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Section 7

2) For the sample data set of Exercise 2 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Give a point estimate for the mean value of y in the sub-population determined by the condition x = 4.

Construct the 90% confidence interval for that mean value.

4) For the sample data set of Exercise 4 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Give a point estimate for the mean value of y in the sub-population determined by the condition x = 2.

Construct the 80% confidence interval for that mean value.

8) For the sample data set of Exercise 8 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Give a point estimate for the mean value of y in the sub-population determined by the condition x = 12.

Construct the 80% confidence interval for that mean value.

Is it valid to make the same estimates for x = 0? Explain.

12) For the data in Exercise 12 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Give a point estimate for the average braking distance of automobiles that weigh 3,250 pounds.

Construct the 80% confidence interval for that mean value.

Is it valid to make the same estimates for 5,000-pound automobiles? Explain.

14) For the data in Exercise 14 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

Give a point estimate for the wave height when the wind speed is 13 miles per hour.

One of the wind speeds in the sample is 13 miles per hour, but the height of waves that day is not what you computed in part (a). Explain why this is not a contradiction.

Construct the 90% confidence interval for the mean wave height on days when the wind speed is 13 miles per hour.

18) For the data in Exercise 18 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

This year 86.2 million acres of corn were planted. Give a point estimate of the number of acres that will be harvested this year.

Explain whether an interval estimate for this problem is a confidence interval or a prediction interval.

Based on your answer to (b), construct an interval estimate for the number of acres that will be harvested this year, at the 99% level of confidence.

20) For the data in Exercise 20 of Chapter 10, Section 2 "The Linear Correlation Coefficient"

You measure the girth of a free-standing oak tree five feet off the ground and obtain the value 127 inches. How old do you estimate the tree to be?

Construct a 90% prediction interval for the age of this tree.

24) Large Data Set 12 lists the golf scores on one round of golf for 75 golfers first using their own original clubs, then using clubs of a new, experimental design (after two months of familiarization with the new clubs).

http://www.flatworldknowledge.com/sites/all/files/data12.xls

Thurio averages 72 strokes per round with his own clubs. Give a point estimate for his score on one round if he switches to the new clubs.

Explain whether an interval estimate for this problem is a confidence interval or a prediction interval.

Based on your answer to (b), construct an interval estimate for Thurios score on one round if he switches to the new clubs, at 90% confidence.

Section 8

2) The table gives the weight x (thousands of pounds) and available heat energy y (million BTU) of a standard cord of various species of wood typically used for heating. Perform a complete analysis of the data, in analogy with the discussion in this section (that is, make a scatter plot, do preliminary computations, find the least squares regression line, find SSE, s, and r, and so on). In the hypothesis test use as the alternative hypothesis 1>0, and test at the 5% level of significance. Use confidence level 95% for the confidence interval for 1. Construct 95% confidence and predictions intervals at at the end.

X y 3.37 23.6 3.50 17.5 4.29 20.14.00 21.6 4.64 28.1

X y 4.99 25.3 4.94 27.0 5.48 30.7 3.26 18.9 4.16 20.7

4) Separate out from Large Data Set 3A just the data on men and do a complete analysis, with shoe size as the independent variable (x) and height as the dependent variable (y). Use .05 and whenever appropriate.

http://www.flatworldknowledge.com/sites/all/files/data3A.xls