Ch. Correlation and Regression. Correlation Interpret Scatter Plots and Correlations MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. ) Given the length of a humanʹs femur,, and the length of a humanʹs humerus,, would ou epect a positive correlation, a negative correlation, or no correlation? A) positive correlation B) negative correlation C) no correlation ) Given the suppl of a commodit,, and the price of a commodit,, would ou epect a positive correlation, a negative correlation, or no correlation? A) negative correlation B) positive correlation C) no correlation ) Given the size of a humanʹs brain,, and their score on an IQ test,, would ou epect a positive correlation, a negative correlation, or no correlation? A) no correlation B) positive correlation C) negative correlation Identif the Eplanator and Response Variables Identif the eplanator variable and the response variable. ) An agricultural business wants to determine if the rainfall in inches can be used to predict the ield per acre on a wheat farm. ) A college counselor wants to determine if the number of hours spent studing for a test can be used to predict the grades on a test. Construct a Scatter Plot and Determine Correlation Provide an appropriate response. ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Construct a scatter plot for the data. Determine whether there is a positive linear correlation, a negative linear correlation, or no linear correlation. Gestation,...... Life span, ) Construct a scatter plot for the given data. Determine whether there is a positive linear correlation, negative linear correlation, or no linear correlation. - - - - - - - - - Page
) Construct a scatter plot for the given data. Determine whether there is a positive linear correlation, negative linear correlation, or no linear correlation. - - - - - - - - - ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. Construct a scatter plot for the data. Hours, Scores, ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Construct a scatter plot for the data. Temperature, Number of absences, ) The data below are the ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. Construct a scatter plot for the data. Age, Pressure, ) The data below are the number of absences and the final grades of randoml selected students from a statistics class. Construct a scatter plot for the data. Number of absences, Final grade, ) A manager wishes to determine the relationship between the number of miles (in hundreds of miles) the managerʹs sales representatives travel per month and the amount of sales (in thousands of dollars) per month. Construct a scatter plot for the data. Miles traveled, Sales, ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below show the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Construct a scatter plot for the data. Number of ears, Grades on test, Page
) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Construct a scatter plot for the data. Rain fall (in inches), Yield (bushels per acre),.................. Perform a Hpothesis Test for a Population Correlation Coefficient MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. ) Calculate the correlation coefficient, r, for the data below. - - - - - - - - - - - - - - A). B). C). D). - - - ) Calculate the correlation coefficient, r, for the data below. - - - - - - - - - - - - - - - A) -. B) -. C) -. D) -. - - - - ) Calculate the correlation coefficient, r, for the data below. - - - - - A) -. B) -. C) -. D) -. ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Calculate the correlation coefficient r. Gestation,...... Life span, ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. Calculate the correlation coefficient, r. Temperature Consumption Page
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. Calculate the correlation coefficient r. Hours, Scores, A). B). C). D). ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Calculate the correlation coefficient, r. Temperature, Number of absences, A). B). C). D). ) The data below are the ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. Calculate the correlation coefficient, r. Age, Pressure, A). B). C). D). ) The data below are the number of absences and the final grades of randoml selected students from a statistics class. Calculate the correlation coefficient, r. Number of absences, Final Grade, A) -. B) -. C) -. D) -. ) A manager wishes to determine the relationship between the number of miles (in hundreds of miles) the managerʹs sales representatives travel per month and the amount of sales (in thousands of dollars) per month. Calculate the correlation coefficient, r. Miles traveled, Sales, A). B). C). D). ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below shows the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Calculate the correlation coefficient, r. Number of ears, Grades on test, A). B). C). D). Page
) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Calculate the correlation coefficient, r. Rain fall (in inches), Yield (bushels per acre),.............. A). B). C). D). ) Given a sample with r =., n =, and α =., determine the standardized test statistic t necessar to test the claim ρ =. Round answers to three decimal places. A). B). C). D). ) Given a sample with r = -., n =, and α =., determine the standardized test statistic t necessar to test the claim ρ =. Round answers to three decimal places. A) -. B) -. C) -. D) -. ) Given a sample with r =., n =, and α =., determine the standardized test statistic t necessar to test the claim ρ =. Round answers to three decimal places. A). B). C). D). ) Given a sample with r = -., n =, and α =., determine the standardized test statistic t necessar to test the claim ρ =. Round answers to three decimal places. A) -. B) -. C) -. D) -. ) Given a sample with r =., n =, and α =., determine the critical values t necessar to test the claim ρ =. A) ±. B) ±. C) ±. D) ±. ) Given a sample with r = -., n =, and α =., determine the critical values t necessar to test the claim ρ =. A) ±. B) ±. C) ±. D) ±. ) Given a sample with r =., n =, and α =., determine the critical values t necessar to test the claim ρ =. A) ±. B) ±. C) ±. D) ±. ) Given a sample with r = -., n =, and α =., determine the critical values t necessar to test the claim ρ =. A) ±. B) ±. C) ±. D) ±. ) Given a sample with r =. and n =, test the significance of the correlation r using α =. and the claim ρ =. Page
) Given a sample with r = -., n =, test the significance of the correlation r using α =. and the claim ρ =. ) Given a sample with r =. and n =, test the significance of the correlation r using α =. and the claim ρ =. ) Given a sample with r = -. and n =, test the significance of the correlation r using α =. and the claim ρ =. ) For the data below, test the significance of the correlation coefficient using α =. and the claim ρ =. - - - - - - - - - - - - - - - - - ) For the data below, test the significance of the correlation coefficient using α =. and the claim ρ =. - - - - - - - - - - - - - - - - ) For the data below, test the significance of the correlation coefficient using α =. and the claim ρ =. - - - - - - - - - - - - - ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Test the significance of the correlation coefficient using α =. and the claim ρ >. Gestation,...... Life span, ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. Test the significance of the correlation coefficient using α =. and the claim ρ =. Hours, Scores, ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Test the significance of the correlation coefficient using α =., and the claim ρ =. Temperature, Number of absences, ) The data below are the ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. Test the significance of the correlation coefficient using α =. and the claim ρ =. Age, Pressure, Page
) The data below are the number of absences and the final grades of randoml selected students from a statistics class. Test the significance of the correlation coefficient using α =. and the claim ρ =. Number of absences, Final Grade, ) A manager wishes to determine the relationship between the number of miles (in hundreds of miles) the managerʹs sales representatives travel per month and the amount of sales (in thousands of dollars) per month. Test the significance of the correlation coefficient using α =. and the claim ρ =. Miles traveled, Sales, ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below shows the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Test the significance of the correlation coefficient using α =. and the claim ρ =. Number of ears, Grades on test, ) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Test the significance of the correlation coefficient using α =. and the claim ρ =. Rain fall (in inches), Yield (bushels per acre),............... ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. Test the significance of the correlation coefficient using α =. and the claim ρ <. Temperature Consumption Calculate the Correlation Coefficient with Interchanged and Provide an appropriate response. ) Calculate the coefficient of correlation, r, letting Row represent the -values and Row represent the -values. Now calculate the coefficient of correlation, r, letting Row represent the -values and Row represent the -values. What effect does switching the eplanator and response variables have on the correlation coefficient? Row Row - - - - - - - - - - - - - - - Page
Concepts Provide an appropriate response. ) Eplain the difference between and. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) If Data A has a correlation coefficient of r = -., and Data B has a correlation coefficient of r =., which correlation is correct? A) Data A and Data B have the same strength in linear correlation. B) Data A has a stronger linear correlation than Data B. C) Data A has a weaker linear correlation than Data B. ) Which of the following values could not represent a correlation coefficient? A). B) C). D) -. Linear Regression Find the Equation of a Regression Line MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. ) Find the equation of the regression line for the given data. - - - - - - - - - - - A) ^ =. -. B) ^ =. -. C) ^ =. +. D) ^ = -. +. ) Find the equation of the regression line for the given data. - - - - - - - - - A) ^ = -. +. B) ^ =. +. C) ^ = -. -. D) ^ =. -. ) Find the equation of the regression line for the given data. - - - - - - - - - A) ^ = -. +. B) ^ =. -. C) ^ =. -. D) ^ = -. +. Page
) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Find the equation of the regression line for the given data. Gestation,...... Life span, MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. Find the equation of the regression line for the given data. Hours, Scores, A) ^ =. +. B) ^ =. -. C) ^^ = -. -. D) ^ = -. +. ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Find the equation of the regression line for the given data. Temperature, Number of absences, A) ^ =. -. B) ^ =. -. C) ^ =. +. D) ^ =. +. ) The data below are ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. Find the equation of the regression line for the given data. Age, Pressure, A) ^ =. +. B) ^ =. -. C) ^ =. -. D) ^^ =. +. ) The data below are the number of absences and the final grades of randoml selected students from a statistics class. Find the equation of the regression line for the given data. Number of absences, Final grade, A) ^ = -. +. B) ^ =. -. C) ^ = -. -. D) ^ = -. +. Page
) A manager wishes to determine the relationship between the number of miles (in hundreds of miles) the managerʹs sales representatives travel per month and the amount of sales (in thousands of dollars) per month. Find the equation of the regression line for the given data. Miles traveled, Sales, A) ^ =. +. B) ^ =. -. C) ^^ =. -. D) ^ =. +. ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below shows the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Find the equation of the regression line for the given data. Number of ears, Grades on test, A) ^ =. +. B) ^ =. -. C) ^ =. -. D) ^ =. +. ) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Find the equation of the regression line for the given data. Rain fall (in inches), Yield (bushels per acre),.................. A) ^ =. +. B) ^ = -. +. C) ^^ =. +. D) ^ =. -. ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. Find the equation of the regression line for the given data. Temperature Consumption MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) Given the equation of a regression line is ^ = -, what is the best predicted value for given =? Assume that the variables and have a significant correlation. A) B) C) D) ) Given the equation of a regression line is ^ = -.-., what is the best predicted value for given =.? Assume that the variables and have a significant correlation. A) -. B) -. C). D). Page
) Given the equation of a regression line is ^ =. -., what is the best predicted value for given = -.? Assume that the variables and have a significant correlation. A) -. B). C) -. D) -. ) Use the regression equation to predict the value of for = -.. Assume that the variables and have a significant correlation. - - - - - - - - - - - A) -. B) -. C). D). ) Use the regression equation to predict the value of for =.. Assume that the variables and have a significant correlation. - - - - - - - - - A) -. B). C) -. D). ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Use the regression equation to predict the life span,, for a gestation period of months,. Assume the variables and have a significant correlation. Gestation,...... Life span, MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. What is the best predicted value for given =? Assume that the variables and have a significant correlation. Hours, Scores, A) B) C) D) ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. What is the best predicted value for given =? Assume that the variables and have a significant correlation. Temperature, Number of absences, A) B) C) D) Page
) The data below are the ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. What is the best predicted value for given =? Assume that the variables and have a significant correlation. Age, Pressure, A) B) C) D) ) The data below are the number of absences and the final grades of randoml selected students from a statistics class. What is the best predicted value for given =? Assume that the variables and have a significant correlation.. Number of absences, Final grade, A) B) C) D) ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below show the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. What is the best predicted value for given =.? Assume that the variables and have a significant correlation. Number of ears, Grades on test, A) B) C) D) ) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Which is the best predicted value for given =.? Assume that the variables and have a significant correlation. Rain fall (in inches), Yield (bushels per acre),.................. A). B). C). D). ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. What is the best-predicted value for the gas consumption,, given = F? Assume that the variables and have a significant correlation. Temperature Consumption Page
) A calculus instructor is interested in finding the strength of a relationship between the final eam grades of students enrolled in Calculus I and Calculus II at his college. The data (in percentages) are listed below. Calculus I Calculus II a) Graph a scatter plot of the data. b) Find an equation of the regression line. c) Determine if there is a significant correlation between the data. Use α =.. d) Predict a Calculus II eam score for a student who receives an in Calculus I. Is our answer a valid prediction? Find the Equation of a Regression Line with Interchanged and Provide an appropriate response. ) Find the equation of the regression line b letting Row represent the -values and Row represent the -values. Now find the equation of the regression line letting Row represent the -values and Row represent the -values. What effect does switching the eplanator and response variables have on the regression line? Row Row - - - - - - - - - - - Concepts MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. ) Given the equation of a regression line is ^ = -. +., determine whether there is a positive linear correlation or a negative linear correlation. A) negative linear correlation B) positive linear correlation ) Given the equation of a regression line is ^ =. +., determine whether there is a positive linear correlation or a negative linear correlation. A) positive linear correlation B) negative linear correlation. Measures of Regression and Prediction Intervals Find Tpes of Variations and the Coefficient of Determination Provide an appropriate response. ) Calculate the coefficient of determination, given that the linear correlation coefficient, r, is.. What does this tell ou about the eplained variation and the uneplained variation of the data about the regression line? ) Calculate the coefficient of determination, given that the linear correlation coefficient, r, is -.. What does this tell ou about the eplained variation and the uneplained variation of the data about the regression line? Page
) Calculate the coefficient of determination, given that the linear correlation coefficient, r, is. What does this tell ou about the eplained variation and the uneplained variation of the data about the regression line? MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) Find the standard error of estimate, se, for the data below, given that ^ = +. A) B) C) D) ) Find the standard error of estimate, se, for the data below, given that ^^ = -.. - - - - A). B). C). D). ) Find the standard error of estimate, se, for the data below, given that ^^ =. -.. - - - - - - - - - - - A). B). C) -. D). ) Find the standard error of estimate, se, for the data below, given that ^^ = -. +.. - - - - - - - - - A). B). C). D). ) Find the standard error of estimate, se, for the data below, given that ^ = -. +.. - - - - - - - - - A). B). C). D). ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Find the standard error of estimate, se, given that ^ =. +.. Gestation,...... Life span, Page
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) The data below are the final eam scores of randoml selected statistics students and the number of hours the studied for the eam. Find the standard error of estimate, se, given that ^ =. +.. Hours, Scores, A). B). C). D). ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Find the standard error of estimate, se, given that ^^ =. -.. Temperature, Number of absences, A). B). C). D). ) The data below are the ages and sstolic blood pressures (measured in millimeters of mercur) of randoml selected adults. Find the standard error of estimate, se, given that ^ =. +.. Age, Pressure, A). B). C). D). ) The data below are the number of absences and the final grades of randoml selected students from a statistics class. Find the standard error of estimate, se, given that ^ = -.X +.. Number of absences, Final grade, A). B). C). D). ) A manager wishes to determine the relationship between the number of miles (in hundreds of miles) the managerʹs sales representatives travel per month and the amount of sales (in thousands of dollars) per month. Find the standard error of estimate, se, given that ^ =. +.. Miles traveled, Sales, A). B). C). D). Page
) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below shows the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Find the standard of estimate, se, given that ^ =. +.. Number of ears, Grades on test, A). B). C). D). ) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Find the standard error of estimate, se, given that ^ =. +.. Rain fall (in inches), Yield (bushels per acre),.................. A). B). C). D). ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. Find the standard error of estimate, se, given that ^ = -. +.. Temperature Consumption Construct and Interpret Prediction Intervals Provide an appropriate response. ) Construct a % prediction interval for given =., ^ = + and se =. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) Construct a % prediction interval for given =., ^ = -. and se =.. Round interval to three decimal places. - - - - A) -. < <. B) -. < <. C) - < < D) - < < - Page
) Construct a % prediction interval for given = -., ^ =. -. and se =.. Round interval to two decimal places. - - - - - - - - - - - A) -. < < -. B) -. < < -. C) -. < < -. D) -. < < -. ) The data below are the gestation periods, in months, of randoml selected animals and their corresponding life spans, in ears. Construct a % prediction interval for, the life span, given = months, ^ =. +., and se =.. Round interval to two decimal places. Gestation,...... Life span, MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. ) The data below are the scores of randoml selected students from a statistics class and the number of hours the studied for the eam. Construct a % prediction interval for, the score on the final eam, given = hours, ^ =. +. and se =.. Round interval to two decimal places. Hours, Scores, A). < <. B). < <. C). < <. D). < <. ) The data below are the temperatures on randoml chosen das during a summer class and the number of absences on those das. Construct a % prediction interval for, the number of das absent, given = degrees, ^ =. -. and se =.. Round interval to three decimal places. Temperature, Number of absences, A). < <. B). < <. C). < <. D). < <. ) In order for applicants to work for the foreign-service department, the must take a test in the language of the countr where the plan to work. The data below shows the relationship between the number of ears that applicants have studied a particular language and the grades the received on the proficienc eam. Construct a % prediction interval for given =., ^^ =. +., and se =.. Round interval to two decimal places. Number of ears, Grades on test, A). < <. B). < <. C). < <. D). < <. Page
) In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the ield of wheat (bushels per acre). Construct a % prediction interval for, the ield, given = inches, ^ =. +. and se =.. Round interval to two decimal places. Rainfall (in inches), Yield (bushels per acre),.................. A). < <. B). < <. C). < <. D). < <. ) The data below are the average monthl temperatures, in F, and the monthl natural gas consumption, in ccf, for a household in northwestern Pennslvania. Construct a % prediction interval for, the monthl gas consumption, given = F. Round interval to two decimal places. Temperature Consumption ) A private organization conducted a surve in regions of the countr to determine the average weekl spending in dollars per person on tobacco products and alcoholic beverages. The data are listed below. Region Alcohol spending, Tobacco spending, $. $. $. $. $. $. $. $. $. $. $. $. $. $. $. $. $. $. a) Construct a scatter plot of the data letting represent spending on alcohol and represent spending on tobacco. b) Find the regression line. c) Find the coefficient of determination. What can ou conclude? d) Find the standard error of estimate, se. e) Construct a % prediction interval for the weekl spending on tobacco when the amount spent on alcohol is $... Multiple Regression Use a Multiple Regression Equation to Predict -values MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. ) A multiple regression equation is ^ = -, + +,, where is a personʹs age, is the personʹs grade point average in college, and is the personʹs income. Predict the income for a person who is ears old and had a college grade point average of.. A) $, B) $, C) $, D) $, ) A researcher found a significant relationship between a studentʹs IQ,, grade point average,, and the score,, on the verbal section of the SAT test. The relationship can be represented b the multiple regression equation ^ = +. +. Predict the SAT verbal score of a student whose IQ is and grade point average is.. A) B) C) D) Page
) A researcher found a significant relationship between a personʹs age,, the number of hours a person works per week,, and the number of accidents,, the person has per ear. The relationship can be represented b the multiple regression equation ^ = -. +. +.. Predict the number of accidents per ear (to the nearest whole number) for a person whose age is and who works hours per week. A) B) C) D) Find a Multiple Regression Equation, Standard Error of Estimate, and Coefficient of Determination Provide an appropriate response. ) A researcher at a local law universit wishes to see whether a studentʹs grade point average and age are related to a studentʹs score on the state bar eam. Si students are randoml selected. The data are given below. Student GPA Age Score...... a) Find a multiple regression equation for the data. b) What is the standard error of estimate? c) What is the coefficient of determination? d) Interpret the results in (c). e) Predict the state bar eam score for a -ear-old student with a grade point average of.. ) A medical researcher wishes to see whether there is a relationship between a personʹs age, cholesterol level, and sstolic blood pressure. Eight people are randoml selected. The data are listed below. Person Age Cholesterol level Blood Pressure a) Find a multiple regression equation for the data. b) What is the standard error of estimate? c) What is the coefficient of determination? d) Interpret the results in (c). e) If a person ears old with a cholesterol reading of is selected, what is that personʹs predicted blood pressure reading? Page
Find the Adjusted Coefficient of Determination Provide an appropriate response. ) A researcher at a local law universit wishes to see whether a studentʹs grade point average and age are related to a studentʹs score on the state bar eam. Si students are randoml selected. The data are given below. Student GPA Age Score...... Calculate the adjusted coefficient of determination, r adj. ) A medical researcher wishes to see whether there is a relationship between a personʹs age, cholesterol level, and sstolic blood pressure. Eight people are randoml selected. The data are listed below. Person Age Cholesterol level Blood Pressure Calculate the adjusted coefficient of determination, r adj. Page
Ch. Correlation and Regression Answer Ke. Correlation Interpret Scatter Plots and Correlations ) A ) A ) A Identif the Eplanator and Response Variables ) eplanator variable: rainfall in inches; response variable: ield per acre ) eplanator variable: hours studing; response variable: grades on the test Construct a Scatter Plot and Determine Correlation ) There appears to be a positive linear correlation. ) There appears to be a negative linear correlation. Page
) There appears to be no linear correlation. ) ) Page
) ) ) Page
) ) Perform a Hpothesis Test for a Population Correlation Coefficient ) A ) A ) A ). ) -. ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) A ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t -.; fail to reject H; There is not sufficient evidence to conclude that a significant correlation eists. Page
) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t -.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t -.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; fail to reject H; There is not sufficient evidence to conclude that a significant correlation eists. ) standardized test statistic t.; critical value t =.; reject H; There is sufficient evidence to conclude that a significant positive correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t -.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; fail to reject H; There is not sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) critical value t = ±.; standardized test statistic t.; reject H; There is sufficient evidence to conclude that a significant correlation eists. ) standardized test statistic t -.; critical value t = -.; reject H; There is sufficient evidence to conclude that a significant negative correlation eists. Calculate the Correlation Coefficient with Interchanged and ) The correlation coefficient remains unchanged. Concepts ) means square each -value and then add the squares, and means add the -values and then square the sum. ) A ) A. Linear Regression Find the Equation of a Regression Line ) A ) A ) A ) ^ =. +. ) A ) A ) A ) A ) A ) A ) A ) ^ = -. +. ) A ) A Page
) A ) A ) A ) About ears. ) A ) A ) A ) A ) A ) A ) About ccf. ) a) See graph below. b) ^ =. -. c) critical value t = ±.; test statistic t =.; reject H; There is sufficient evidence to conclude that a significant correlation eists. d) When =, =. This is a valid prediction as there is a significant correlation between the data. Find the Equation of a Regression Line with Interchanged and ) The sign of m is unchanged, but the values of m and b change. Concepts ) A ) A. Measures of Regression and Prediction Intervals Find Tpes of Variations and the Coefficient of Determination ) The coefficient of determination, r, =.. That is,.% of the variation is eplained and.% of the variation is uneplained. ) The coefficient of determination, r, =.. That is,.% of the variation is eplained and.% of the variation is uneplained. ) The coefficient of determination, r, =. That is, % of the variation is eplained and there is no variation that is uneplained. ) A ) A ) A ) A ) A ). ) A ) A ) A Page
) A ) A ) A ) A ). Construct and Interpret Prediction Intervals ) Since se =, there is no interval for =.. ) A ) A ). < <. ) A ) A ) A ) A ). < <. ) a) b) ^ =. +. c) r =.. This means that about.% of the variation can be eplained. About.% of the variation is uneplained and is due to chance or other variables. d) se =. e). < <.. Multiple Regression Use a Multiple Regression Equation to Predict -values ) A ) A ) A Find a Multiple Regression Equation, Standard Error of Estimate, and Coefficient of Determination ) a) ^ = -. +. +. b) se =. c) r =.. d) The multiple regression model eplains % of the variation in. e) ) a) ^ =. +. +. b) se =. c) r =.. d) The multiple regression equation eplains.% of the variation in. e) Page
Find the Adjusted Coefficient of Determination ) r adj. =. ) r adj. =. Page