Question 1

After controlling for Z, the partial correlation coefficient is .78. The bivariate Pearson's r between X and Y was only .51. What should the researcher do next?
A) Use
B) Halt the investigation since these results are mathematically impossible
C) Conclude that the relationship between Z and Y is direct
D) Conclude that the relationship between Z and Y is spurious

Accepted Answer

The partial correlation coefficient being higher than the bivariate Pearson's r suggests that Z is a suppressor variable, which enhances the relationship between X and Y when controlled for. The researcher should use this information to further investigate the role of Z.

Question 2

After controlling for Z, a researcher finds evidence of a direct relationship between X and Y. What step should be taken next?
A) Z should become the new independent variable
B) Z should become the new dependent variable
C) Z should be disregarded and a new control variable should be selected
D) Z should be disregarded and a new independent variable should be selected

Accepted Answer

Explanation: If a direct relationship between X and Y is found after controlling for Z, it suggests that Z does not confound the relationship. Therefore, Z can be disregarded, and the researcher may consider selecting a new control variable to further validate the relationship.

Question 3

Partial and multiple correlation require data which are					
A) nominal or ordinal
B) ordinal only
C) inferential and bivariate
D) interval-ratio

Accepted Answer

Partial and multiple correlation require data that are measured on an interval or ratio scale, as they involve computing correlations between continuous variables while controlling for the effects of other variables. Nominal and ordinal data only provide categorical information and cannot be used for these types of analyses.

Question 4

A researcher examines the relationship between poverty and crime rates for 100 metropolitan areas and finds a zero-order correlation of 0.37. She controls for the percent of families that are headed by single parents and finds a first order partial correlation of 0.06. Which of the following correctly describes this outcome? This is a ______ relationship
A) direct
B) statistically significant
C) spurious
D) interactive

Accepted Answer

The zero-order correlation between poverty and crime rates suggests a positive relationship between the two variables, but the first-order partial correlation becomes very weak after controlling for the percentage of single-parent families, indicating that the relationship between poverty and crime rates is spurious. The percentage of single-parent families is a confounding variable that explains much of the association between poverty and crime rates.

Question 5

A Pearson's r calculated for the bivariate relationship between X and Y is .50. After controlling for Z, the partial correlation coefficient is .49. This outcome would be evidence of a(n) _____________ relationship between X and Y.
A) direct
B) spurious
C) interactive
D) negative

Accepted Answer

The answer of A Pearson's r calculated for the bivariate...

Question 6

After controlling for Z, a researcher finds evidence of a spurious relationship between X and Y. What step should be taken next?
A) Z should become the new independent variable
B) Z should become the new dependent variable
C) Z should be disregarded and a new control variable should be selected
D) Z should be disregarded and a new independent variable should be selected

Accepted Answer

When a researcher finds evidence of a spurious relationship between X and Y after controlling for Z, it indicates that Z is the actual cause affecting both X and Y. Therefore, making Z the new independent variable is a logical next step to understand its influence on the dependent variable (previously thought to be influenced directly by X).

Question 7

Which of the following would be consistent with a causal model in which X and Z had independent and uncorrelated causal effects on Y?
A) Pearson's r is .37, partial correlation coefficient is .36
B) Pearson's r is .30, partial correlation coefficient is .50
C) Pearson's r is -.10, partial correlation coefficient is -.01
D) Pearson's r is -.41 partial correlation coefficient is .00

Accepted Answer

The answer of Which of the following would be consistent...

Question 8

After controlling for Z, the partial correlation coefficient is .78. The bivariate Pearson's r between X and Y was only .51. Which interpretation is consistent with these results?
A) None, these results are mathematically impossible.
B) There is a spurious relationship between X and Y
C) X and Z are both caused by Y
D) X and Z are separate, uncorrelated causes of Y

Accepted Answer

The partial correlation coefficient indicates the relationship between X and Y that cannot be explained by Z. A strong partial correlation (in this case .78) suggests that when Z is controlled for, there is still a strong relationship between X and Y. This indicates that X and Y are separate, uncorrelated causes of Y. The low bivariate Pearson's r between X and Y may suggest that there is a weak direct relationship between X and Y, but the strong partial correlation suggests that this relationship is largely accounted for by the influence of Z. The spurious relationship option (B) would suggest that the relationship between X and Y only exists because of the influence of Z, which is not consistent with the high partial correlation. Option C suggests that Y causes both X and Z, but the question is framed as X and Y being independent variables, so this is not an appropriate interpretation. Option A is incorrect because these results are mathematically possible.

Question 9

Partial and multiple correlation are based on	    
A) bivariate tables
B) random sampling
C) the Analysis of Variance
D) Pearson's r

Accepted Answer

Partial and multiple correlation are based on Pearson's r, which measures the degree of association between two variables while controlling for the influence of one or more other variables. Bivariate tables refer to two variables only, random sampling refers to the method of selecting a subset from a larger population, and the Analysis of Variance is a statistical method used for comparing the means of two or more groups.

Question 10

The 'first-order' partial correlation coefficient measures
A) the bivariate relationship between X and Y
B) the relationship between the dependent and control variables
C) the bivariate relationship after controlling for the third variable
D) the bivariate relationship after controlling for the fourth variable

Accepted Answer

The first-order partial correlation coefficient measures the bivariate relationship between X and Y after controlling for the third variable, making choice C the correct answer. Options A and B are incorrect because they refer to simple correlation coefficients, not partial correlation coefficients. Option D is incorrect because it refers to a higher order partial correlation coefficient, not the first order partial correlation coefficient.

Question 11

Which of the following would be consistent with a spurious relationship between X and Y?
A) Pearson's r is .37, partial correlation coefficient is .36
B) Pearson's r is .78, partial correlation coefficient is .30
C) Pearson's r is -.10, partial correlation coefficient is -.15
D) Pearson's r is .00, partial correlation coefficient is .00

Accepted Answer

In a spurious relationship, the correlation between X and Y is high due to the influence of a third variable. In this case, a high Pearson's r (.78) indicates a strong relationship between X and Y, but a low partial correlation coefficient (.30) suggests that when the influence of a third variable is removed, the relationship between X and Y is not significant. This is consistent with a spurious relationship. Choices A, C, and D do not meet the criteria for a spurious relationship.

Question 12

After controlling for Z, the partial correlation coefficient between X and Y is the same value as the bivariate Pearson's r. This pattern would be taken as evidence of
A) a direct relationship between X and Y
B) a spurious relationship between X and Z
C) interaction between X, Y, and Z
D) an intervening relationship between X and Y, interaction between X and Z

Accepted Answer

If the partial correlation between X and Y after controlling for Z is the same as the bivariate Pearson's r, it suggests that the relationship between X and Y is direct and not confounded by Z. If there was spurious or intervening or interaction effects, the partial correlation would not be the same as the bivariate Pearson's r.

Question 13

A researcher examines the relationship between poverty and crime rates for 100 metropolitan areas and finds a zero-order correlation of 0.37. She controls for the percent of families that are headed by single parents and finds a first order partial correlation of 0.33. Which of the following correctly describes this outcome? This is a ______ relationship
A) direct
B) statistically significant
C) spurious
D) interactive

Accepted Answer

The relationship is direct because the correlation remains positive and relatively strong even after controlling for the percent of families headed by single parents, indicating that the relationship between poverty and crime rates is not entirely explained by this third variable.

Question 14

Partial correlation will detect all of the following relationships among variables except
A) interaction
B) direct relationships
C) spurious relationships
D) intervening relationships

Accepted Answer

Partial correlation is used to determine the relationship between two variables while controlling the effects of one or more other variables. It is good at detecting direct, spurious, and intervening relationships but cannot detect interactions between variables.

Question 15

An analysis of the relationship between income and education found a correlation of 0.43. After controlling for age, the partial correlation was 0.43. The relationship between income and education seems to be
A) direct
B) spurious
C) intervening
D) interactive

Accepted Answer

The correlation coefficient, both the original and the partial, is positive and indicates a direct relationship between income and education. The fact that the partial correlation is the same as the original correlation after controlling for age suggests that age is not a confounding variable and the relationship between income and education is not spurious. There is also no indication of an intervening or interactive relationship.

Question 16

When examining a bivariate relationship using Pearson's r, the partial correlation computed while using one control variable is called
A) the first-order partial correlation coefficient
B) the second-order partial correlation coefficient
C) the intervening partial correlation coefficient
D) the

Accepted Answer

The first-order partial correlation coefficient is the partial correlation computed while using one control variable.

Question 17

The partial correlation coefficient will reveal an interactive relationship between three variables when
A) the partial correlation coefficients drops to zero
B) the partial is greater in value than the zero-order correlation coefficient
C) the partial correlation coefficient is negative
D) none of the above. Partial correlation will not detect interaction

Accepted Answer

Partial correlation can reveal the strength of the relationship between two variables while controlling for the influence of one or more additional variables. However, it cannot detect interactions between variables. Therefore, none of the options (A, B or C) are correct in this context.

Question 18

The partial correlation coefficient between X and Y after controlling for Z shows a much weaker relationship than the Pearson's r computed for X and Y. This would be taken as evidence of a(n) _____________ relationship between X and Y.
A) direct
B) spurious or intervening
C) interactive
D) positive

Accepted Answer

The fact that the partial correlation between X and Y is weaker than the Pearson's r suggests that the relationship between X and Y is partly explained by the relationship between X and Z, and the relationship between Z and Y. This is indicative of a spurious or intervening relationship.

Question 19

Which of the following would be consistent with a direct relationship between X and Y?
A) Pearson's r is .17, partial correlation coefficient is .16
B) Pearson's r is .78, partial correlation coefficient is .50
C) Pearson's r is .10, partial correlation coefficient is .20
D) Pearson's r is .00, partial correlation coefficient is .00

Accepted Answer

The answer of Which of the following would be consistent...

Question 20

A Pearson's r calculated for a bivariate relationship is .50. After controlling for Z, the partial correlation coefficient is .07. This outcome would be evidence of a(n) _____________ relationship between X and Y.
A) direct
B) spurious or intervening
C) interactive
D) positive

Accepted Answer

The significant decrease in the correlation coefficient after controlling for Z suggests that the relationship between X and Y may have been spurious or intervened by Z. The low value of the partial correlation coefficient (.07) implies that after statistically controlling for Z, there is hardly any relationship remaining between X and Y.

Quiz 13: Partial Correlation and

After controlling for Z, the partial correlation coefficient is .78. The bivariate Pearson's r between X and Y was only .51. What should the researcher do next?

After controlling for Z, a researcher finds evidence of a direct relationship between X and Y. What step should be taken next?

Partial and multiple correlation require data which are

A Pearson's r calculated for the bivariate relationship between X and Y is .50. After controlling for Z, the partial correlation coefficient is .49. This outcome would be evidence of a(n) _____________ relationship between X and Y.

After controlling for Z, a researcher finds evidence of a spurious relationship between X and Y. What step should be taken next?

Which of the following would be consistent with a causal model in which X and Z had independent and uncorrelated causal effects on Y?

After controlling for Z, the partial correlation coefficient is .78. The bivariate Pearson's r between X and Y was only .51. Which interpretation is consistent with these results?

Partial and multiple correlation are based on

The 'first-order' partial correlation coefficient measures

Which of the following would be consistent with a spurious relationship between X and Y?

After controlling for Z, the partial correlation coefficient between X and Y is the same value as the bivariate Pearson's r. This pattern would be taken as evidence of

Partial correlation will detect all of the following relationships among variables except

An analysis of the relationship between income and education found a correlation of 0.43. After controlling for age, the partial correlation was 0.43. The relationship between income and education seems to be

When examining a bivariate relationship using Pearson's r, the partial correlation computed while using one control variable is called

The partial correlation coefficient will reveal an interactive relationship between three variables when

The partial correlation coefficient between X and Y after controlling for Z shows a much weaker relationship than the Pearson's r computed for X and Y. This would be taken as evidence of a(n) _____________ relationship between X and Y.

Which of the following would be consistent with a direct relationship between X and Y?

A Pearson's r calculated for a bivariate relationship is .50. After controlling for Z, the partial correlation coefficient is .07. This outcome would be evidence of a(n) _____________ relationship between X and Y.