Questions and answers for exam Preparation

MCQs

Total Questions : 61 | Page 4 of 7 pages

Question 31. If the coefficient of determination is equal to 1, then the correlation coefficient

must also be equal to 1
can be either -1 or +1
can be any value between -1 to +1
must be -1

Discuss Question

Answer: Option B. -> can be either -1 or +1

Question 32. In regression analysis, if the independent variable is measured in kilograms, the dependent
variable

must also be in kilograms
must be in some unit of weight
cannot be in kilograms
can be any units

Discuss Question

Answer: Option D. -> can be any units

Question 33. In a regression analysis if SSE = 200 and SSR = 300, then the coefficient of determination is

0.6667
0.6000
0.4000
1.5000

Discuss Question

Answer: Option B. -> 0.6000

Question 34. If the correlation coefficient is 0.8, the percentage of variation in the response variable explained
by the variation in the explanatory variable is

0.80%
80%
0.64%
64%

Discuss Question

Answer: Option D. -> 64%

Question 35. If the correlation coefficient is a positive value, then the slope of the regression line

must also be positive
can be either negative or positive
can be zero
can not be zero

Discuss Question

Answer: Option A. -> must also be positive

Question 36. If the coefficient of determination is 0.81, the correlation coefficient

is 0.6561
could be either + 0.9 or - 0.9
must be positive
must be negative

Discuss Question

Answer: Option B. -> could be either + 0.9 or - 0.9

Question 37. A fitted least squares regression line

may be used to predict a value of y if the corresponding x value is given
is evidence for a cause-effect relationship between x and y
can only be computed if a strong linear relationship exists between x and y
None of these alternatives is correct.

Discuss Question

Answer: Option A. -> may be used to predict a value of y if the corresponding x value is given

Question 38. 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]

0.40
0.30
0.533
cannot be determined from information given
none of these

Discuss Question

Answer: Option A. -> 0.40

Question 39. Assume the same variables as in question 28 above; height is measured in feet and weight is
measured in pounds. Now, suppose that the units of both variables are converted to metric (meters
and kilograms). The impact on the slope is:

the sign of the slope will change
the magnitude of the slope will change
both a and b are correct
neither a nor b are correct

Discuss Question

Answer: Option B. -> the magnitude of the slope will change

Question 40. Suppose that you have carried out a regression analysis where the total variance in the response is
133452 and the correlation coefficient was 0.85. The residual sums of squares is: