A. the sign of the slope will change
B. the magnitude of the slope will change
C. both a and b are correct
D. neither a nor b are correct
✅ The correct answer is option A.
Statistics MCQs
Suppose the correlation coefficient between height (as measured in feet) versus weight (as measured in pounds) is 0.40. What is the correlation coefficient of height measured in inches versus weight measured in ounces? [12 inches = one foot; 16 ounces = one pound] _______
A. 0.40
B. 0.30
C. 0.533
D. cannot be determined from information given e. none of these
✅ The correct answer is option A.
Regression analysis was applied between $ sales (y) and $ advertising (x) across all the branches of a major international corporation. The following regression function was obtained) ! = 5000 + 7.25x If the advertising budgets of two branches of the corporation differ by ,000, then what will be the predicted difference in their sales? __________
A. 7,500
B. 2,500
C. 00
D. .25
✅ The correct answer is option A.
A fitted least squares regression line ____________
A. may be used to predict a value of y if the corresponding x value is given
B. is evidence for a cause-effect relationship between x and y
C. can only be computed if a strong linear relationship exists between x and y
D. None of these alternatives is correct.
✅ The correct answer is option B.
If the coefficient of determination is 0.81, the correlation coefficient __________
A. is 0.6561
B. could be either + 0.9 or – 0.9
C. must be positive
D. must be negative
✅ The correct answer is option A.
If the correlation coefficient is a positive value, then the slope of the regression line ___________
A. must also be positive
B. can be either negative or positive
C. can be zero
D. can not be zero
✅ The correct answer is option D.
If the correlation coefficient is 0.8, the percentage of variation in the response variable explained by the variation in the explanatory variable is____________
A. 0.80%
B. 80%
C. 0.64%
D. 64%
✅ The correct answer is option B.
The data are the same as for question 4 above. The relationship between number of beers consumed (x) and blood alcohol content (y) was studied in 16 male college students by using least squares regression. The following regression equation was obtained from this study: != -0.0127 + 0.0180x Suppose that the legal limit to drive is a blood alcohol content of 0.08. If Ricky consumed 5 beers the model would predict that he would be____________
A. 0.09 above the legal limit
B. 0.0027 below the legal limit
C. 0.0027 above the legal limit
D. 0.0733 above the legal limit
✅ The correct answer is option B.
In regression analysis, if the independent variable is measured in kilograms, the dependent variable ______
A. must also be in kilograms
B. must be in some unit of weight
C. cannot be in kilograms
D. can be any units
✅ The correct answer is option D.