Deck 4: Regression and Correlation Analysis

Question 1

If one of the regression coefficient is greater than unity, the other must be:

A)More than Unity
B)Less than Unity
C)Unity
D)none

Answer 1

B

Question 2

The regression coefficients re independent of change of origin but:

A)Not of Scale
B)Also of Scale
C)No Change in scale
D)none

Answer 2

A

Question 3

The coefficient of correlation between the regression coefficients is:

A)Arithmetic Mean
B)Geometric Mean
C)Average
D)none

Answer 3

B

Question 4

The correlation coefficient is used to determine:

A)A specific value of the y-variable given a specific value of the x-variable
B)A specific value of the x-variable given a specific value of the y-variable
C)The strength of the relationship between the x and y variables
D)None of these

Question 5

If there is a very strong correlation between two variables then the correlation coefficient must be:

A)any value larger than 1
B)much smaller than 0, if the correlation is negative
C)much larger than 0, regardless of whether the correlation is negative or positive
D)None of these alternatives is correct

Question 6

In regression, the equation that describes how the response variable (y) is related to the explanatory variable (x) is:

A)the correlation model
B)the regression model
C)used to compute the correlation coefficient
D)None of these alternatives is correct.

Question 7

In regression analysis, the variable that is used to explain the change in the outcome of an experiment, or some natural process, is called:

A)the x-variable
B)the independent variable
C)the predictor variable
D)the explanatory variable

Question 8

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

Question 9

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

Question 10

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

Question 11

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

Question 12

Let the coefficient of determination computed to be 0.39 in a problem involving one independent variable and one dependent variable. This result means that:

A)The relationship between two variables is negative
B)The correlation coefficient is 0.39 also
C)39% of the total variation is explained by the independent variable
D)39% of the total variation is explained by the dependent variable

Question 13

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

Question 14

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.

Question 15

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

Question 16

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.

Question 17

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

Question 18

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

Question 19

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