# ( Best 225+ ) Business Statistics MCQ

## 121. The value of a correlation is reported by a researcher to be r = −0.5. Which of the following statements is correct?

A. The x-variable explains 25% of the variability in the y-variable.

B. The x-variable explains −25% of the variability in the y-variable.

C. The x-variable explains 50% of the variability in the y-variable.

D. The x-variable explains −50% of the variability in the y-variable.

## 122. Past data has shown that the regression line relating the final exam score and the midterm exam score for students who take statistics from a certain professor is: final exam = 50 + 0.5 × midterm One interpretation of the slope is

A. a student who scored 0 on the midterm would be predicted to score 50 on the final exam.

B. a student who scored 0 on the final exam would be predicted to score 50 on the midterm exam.

C. a student who scored 10 points higher than another student on the midterm would be

D. predicted to score 5 points higher than the other student on the final exam. students only receive half as much credit (.5) for a correct

## 123. One use of a regression line is

A. to determine if any x-values are outliers.

B. to determine if any y-values are outliers.

C. to determine if a change in x causes a change in y.

D. to estimate the change in y for a one-unit change in x.

## 124. The percent of total variation of the dependent variable Y explained by the set of independent variables X is measured by

A. Coefficient of Correlation

B. Coefficient of Skewness

C. Coefficient of Determination

D. Standard Error or Estimate

## 125. The strength (degree) of the correlation between a set of independent variables X and a dependent variable Y is measured by

A. Coefficient of Correlation

B. Coefficient of Determination

C. Standard error of estimate

D. All of the above

## 126. A coefficient of correlation is computed to be -0.95 means that

A. The relationship between two variables is weak.

B. The relationship between two variables is strong and positive

C. The relationship between two variables is strong and but negative

D. Correlation coefficient cannot have this value

## 127. Relationship between correlation coefficient and coefficient of determination is that

A. both are unrelated

B. The coefficient of determination is the coefficient of correlation squared

C. The coefficient of determination is the square root of the coefficient of correlation

D. both are equal

## 128. The sample coefficient of correlation

A. Has the same sign as the slope, i.e. β

B. Can range from -1.00 up to 2.00

C. Is also called Peterson’s r

D. Can range from -3.00 up to 2.00

## 129. The regression equation is the line with slope a passing through

A. The point (X¯¯¯¯,Y¯¯¯¯)

B. The point (Y, X)

C. The point (X, Y)

D. The point (Y¯¯¯¯,X¯¯¯¯)

## 130. In regression equation y=a+βx+e, both x and y variables are

A. y is fixed and x is random

B. Random

C. Fixed

D. x is fixed and y is random