Question 1

A ______ variable is one that helps explain under what conditions a correlation between two variables exists.

Accepted Answer

A moderating variable is one that influences the strength or direction of the relationship between two other variables, explaining under what conditions a correlation exists.

Question 2

By using a __________ procedure, Eron and his colleagues (1972)were able to rule out several potential third variables that might have affected the relationship they found between preference for TV violence and aggressiveness.

Accepted Answer

Partial correlation is a statistical technique that allows researchers to examine the relationship between two variables while controlling for the effects of one or more other variables. In this case, Eron and his colleagues used partial correlation to rule out several potential third variables that might have affected the relationship they found between preference for TV violence and aggressiveness.

Question 3

A ______ variable is one that helps explain why a correlation between two variables exists.

Accepted Answer

A mediating variable explains the process or mechanism through which two variables are related, helping to clarify the nature of their correlation.

Question 4

In the textbook example, impulse control helps explain why a correlation between alcohol use and engaging in risky sex. In this case, impulse control is a ______ variable.

Accepted Answer

Impulse control is a mediating variable because it explains the mechanism through which alcohol use leads to engaging in risky sex.

Question 5

Suppose there is a high positive correlation between reading speed and reading comprehension. You suspect that IQ is a potential third variable. You complete a partial correlation procedure and, with IQ controlled statistically, the high correlation between speed and comprehension remains. What do you conclude?

Accepted Answer

The partial correlation procedure controls for IQ, and since the high correlation between speed and comprehension remains, IQ can be ruled out as a third variable affecting the correlation.

Question 6

In the textbook example, the type of living conditions helps explain under what conditions a correlation between alcohol use and engaging in risky sex. In this case, living condtion is a ______ variable.

Accepted Answer

A moderating variable is one that influences the strength or direction of the relationship between two other variables. In this case, living conditions affect the correlation between alcohol use and engaging in risky sex.

Question 7

Suppose there is a high positive correlation between reading speed and reading comprehension. You suspect that IQ is a potential third variable. You complete a partial correlation procedure and, with IQ controlled statistically, the high correlation between speed and comprehension virtually disappears. What do you conclude?

Accepted Answer

The disappearance of the correlation when IQ is controlled suggests that IQ was influencing both reading speed and comprehension, making it an important third variable.

Quiz 9: Non-Experimental Design I: Survey Methods

A ______ variable is one that helps explain under what conditions a correlation between two variables exists.

By using a __________ procedure, Eron and his colleagues (1972) were able to rule out several potential third variables that might have affected the relationship they found between preference for TV violence and aggressiveness.

A ______ variable is one that helps explain why a correlation between two variables exists.

In the textbook example, impulse control helps explain why a correlation between alcohol use and engaging in risky sex. In this case, impulse control is a ______ variable.

In the textbook example, the type of living conditions helps explain under what conditions a correlation between alcohol use and engaging in risky sex. In this case, living condtion is a ______ variable.