Question 1

When an independent variable such as task difficulty has been shown to interact with a second independent variable such as age,the generality (i.e.,ability to generalize the findings)of the effect of the task difficulty variable is
A) complete.
B) unaffected.
C) limited.
D) increased.

Accepted Answer

When an independent variable interacts with another independent variable, it means that the effect of the first independent variable is dependent on the second independent variable. Therefore, the generality of the effect of the task difficulty variable is limited and cannot be generalized to all age groups since the effect is dependent on age.

Question 2

When no interaction effect occurs in a complex design with two independent variables,we know the effects of each independent variable can be generalized
A) only across the characteristics of the participants tested in the experiment.
B) only across the two independent variables included in the experiment.
C) across all factors held constant in the experiment.
D) beyond the conditions that were included in the experiment.

Accepted Answer

The answer of When no interaction effect occurs in a...

Question 3

A potential solution to the problem of drawing causal inferences based on the natural groups design is to use a complex design involving a natural groups design for an individual differences variable along with a manipulated independent variable.An important key to this potential solution is to
A) obtain a main effect of the individual differences variable but not of the manipulated independent variable.
B) obtain a main effect of the manipulated independent variable but not of the individual differences variable.
C) obtain main effects of both the individual differences variable and the manipulated independent variable.
D) obtain an interaction effect of the individual differences variable and the manipulated independent variable.

Accepted Answer

In order to draw causal inferences based on the natural groups design, a complex design involving a natural groups design for an individual differences variable along with a manipulated independent variable should be used. The potential solution would be to obtain an interaction effect of the individual differences variable and the manipulated independent variable. This would indicate that the effect of the independent variable differs for individuals based on their individual differences variable, allowing for causal inferences to be drawn. Obtaining main effects for both variables or only one variable would not necessarily provide a solution to the problem of drawing causal inferences based on natural groups design.

Question 4

A common approach for resolving contradictory findings in research literature is to develop a theory for the source of different findings and
A) create experimental conditions that will lead to a floor effect for one set of findings.
B) examine the relationship between a natural groups variable and a dependent variable.
C) manipulate independent variables in a complex design to test the theory.
D) eliminate any possibility for statistical interactions among the independent variables.

Accepted Answer

Manipulating independent variables in a complex design to test a theory is a common approach for resolving contradictory findings in research literature. By doing so, researchers can explore the relationship between different variables and assess whether the differences in findings can be explained by different manipulations or conditions. This approach allows for a more nuanced and detailed understanding of the underlying causes of the contradictory findings. A and D are not appropriate choices as they focus on limiting or isolating variables rather than exploring relationships, and B is not sufficient for addressing contradictory findings as it does not provide a mechanism for explaining differences in results.

Question 5

.The two independent variables are speed of the presentation (250 msec,1000 msec)and brightness of the background (dark,light).Speed of presentation is a repeated measures variable,and brightness of the background is a random groups variable.Suppose the following mean were observed.What should the researcher conclude? 
A) The two independent variables are not relevant variables in this experiment.
B) The main effect of the brightness variable is larger than the main effect of the speed of presentation variable.
C) The brightness variable should have been manipulated as a natural groups variable.
D) The interaction may be uninterpretable due to a possible floor effect.

Accepted Answer

The question suggests that there may be a floor effect, which could make it difficult to interpret the interaction effect between speed of presentation and brightness of background. Therefore, it is best to choose option D and conclude that the interaction may be uninterpretable due to a possible floor effect. The other options are not supported by the information given in the question.

Question 6

There are several steps an investigator must take in carrying out the general procedure for drawing causal inferences based on the natural groups design.Which of the following is not one of the steps an investigator must take?
A) Develop a theory explaining why a difference should occur between groups differentiated on the basis of an individual differences variable.
B) Select an independent variable that can be manipulated and that should influence the likelihood that the theoretical process will occur.
C) Select a second individual differences variable that would be expected to interact with the primary individual differences variable.
D) Strive to produce an interaction effect between a manipulated independent variable and the primary individual differences variable.

Accepted Answer

The answer of There are several steps an investigator must...

Question 7

The limits of the external validity of the effects of each of the two independent variables in a complex design are specified when
A) there is no interaction effect of the two variables and neither variable produces a main effect.
B) there is no interaction effect of the two variables but significant main effects for both variables.
C) there is no interaction effect of the two variables and one independent variable has a main effect but the other variable does not.
D) there is an interaction effect of the two variables and main effects of the variables may or may not be present.

Accepted Answer

When there is an interaction effect of the two independent variables in a complex design, the limits of the external validity of their effects cannot be specified without considering the nature and direction of the interaction. Additionally, main effects may or may not be present, making it difficult to determine the independent effects of each variable on the outcome. Hence, option D is the correct answer.

Question 8

In a 2 * 2 complex design,one independent variable was shown not to have a statistically significant main effect on the dependent variable.Based on this,we can state that
A) the independent variable has external validity over the levels of the second independent variable.
B) it is not a relevant independent variable.
C) for the variable to be considered relevant in this experiment, it must interact with the second independent variable.
D) the variable will definitely interact with the second independent variable in this experiment.

Accepted Answer

The lack of a statistically significant main effect does not render an independent variable irrelevant; it may still interact with another variable to influence the dependent variable, suggesting its relevance could be conditional on the levels of the other variable.

Question 9

An interaction effect is likely to be uninterpretable when this problem in measurement occurs:
A) simple main effect
B) ceiling or floor effect
C) nonparallel lines
D) highly reliable measurement of the dependent variable

Accepted Answer

When there is a ceiling or floor effect, the data is heavily skewed towards one end of the scale, making it difficult to interpret the interaction effect. This occurs when a significant proportion of participants score at the highest or lowest possible value on the measurement scale.

Question 10

Suppose an independent variable does not have any effect on the dependent variable in a single-factor experiment.Which of the following is one of the reasons for being cautious about saying that the independent variable is irrelevant?
A) We know the independent variable could interact with another independent variable when used in a complex design.
B) We can assume this independent variable would not have an effect if different levels of the variable had been tested.
C) We know that experiments in which an independent variable does not have an effect are inherently uninterpretable.
D) We know that single-factor experiments cannot be used to identify relevant independent variables.

Accepted Answer

Even though the independent variable did not have an effect in the single-factor experiment, it is possible that it may interact with another independent variable in a more complex design. Therefore, we should be cautious about saying that it is irrelevant.

Question 11

The natural groups design is effective for establishing
A) correlations between individuals' characteristics and their performance on a task.
B) floor effects for relating individuals' characteristics and their performance on a task.
C) causal inferences between individuals' characteristics and their performance on a task.
D) spurious relationships between individuals' characteristics and their performance on a task.

Accepted Answer

The natural groups design involves observing and comparing pre-existing groups of individuals with different characteristics. This allows for the examination of correlations between individuals' characteristics and their performance on a task. However, it does not allow for establishing causal inferences or spurious relationships, and floor effects are not necessarily relevant to this particular design.

Quiz 8: Complex Designs

When an independent variable such as task difficulty has been shown to interact with a second independent variable such as age,the generality (i.e.,ability to generalize the findings) of the effect of the task difficulty variable is

When no interaction effect occurs in a complex design with two independent variables,we know the effects of each independent variable can be generalized

A potential solution to the problem of drawing causal inferences based on the natural groups design is to use a complex design involving a natural groups design for an individual differences variable along with a manipulated independent variable.An important key to this potential solution is to

A common approach for resolving contradictory findings in research literature is to develop a theory for the source of different findings and

There are several steps an investigator must take in carrying out the general procedure for drawing causal inferences based on the natural groups design.Which of the following is not one of the steps an investigator must take?

The limits of the external validity of the effects of each of the two independent variables in a complex design are specified when

In a 2 * 2 complex design,one independent variable was shown not to have a statistically significant main effect on the dependent variable.Based on this,we can state that

An interaction effect is likely to be uninterpretable when this problem in measurement occurs:

Suppose an independent variable does not have any effect on the dependent variable in a single-factor experiment.Which of the following is one of the reasons for being cautious about saying that the independent variable is irrelevant?

The natural groups design is effective for establishing