Exam 8: Complex Designs

A researcher designs a 2 * 2 * 2 complex design in which the first independent variable uses a random groups design,the second independent variable uses a natural groups design,and the third independent variable uses a repeated measures design.The researcher wants to have 20 participants in each independent groups condition.How many participants will she need to recruit?

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?

Complex designs beyond the basic 2 * 2 design can be constructed

A researcher was interested in the effects of arousal and personality on individuals' GRE test performance.The personality variable he examined was individuals' level of introversion-extraversion.Based on questionnaire responses,each participant was classified as an "extravert" or an "introvert." The researcher manipulated arousal level by giving caffeine to participants prior to administering a practice GRE test.Participants were randomly assigned to a high-caffeine condition,a medium-caffeine condition,or the no-caffeine condition.All participants then completed a version of the quantitative portion of the GRE. Suppose the researcher observed the following means for each group: Explain whether the following two statements are True or False based on the evidence in this experiment. (1)We can predict individuals' quantitative GRE score if we know whether they are introverts or extraverts. (2)Individuals' level of introversion or extraversion causes different performance on the quantitative GRE test.

When a line graph is used to depict the results of a complex design,an interaction effect is indicated by

Use this graph to answer the question that follow: Use the graph to determine the means for the main effect of Task Complexity.[Be sure to specify which mean belongs with each condition.]

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

The analysis plan and interpretation of the results of a complex design experiment involving two independent variables depends on

.He is also interested in knowing whether high or low test-anxious individuals' performance is different for the computerized version of the two tests compared to the paper-and-pencil version of the tests.Within each anxiety group,he randomly assigns participants to either the computer version or the paper version of the GRE tests.Participants then complete both the verbal and quantitative tests of the GRE in the test version they've been assigned (computer or paper).Thus,each participant has two scores,a Verbal score and a Quantitative score. Assume the following results were observed for the mean Verbal scores (we'll ignore Quantitative scores): Based on these findings,the researcher claims that Test Version,computer vs.paper,does not affect individuals' average performance.What information is the researcher using to make this claim? Is this claim justified?

Using the data in the following table,determine the two values that represent the main effect of the Test Anxiety independent variable:

In a complex factorial design described as a 2 * 4,there are

Distinguish between a main effect and an interaction effect in a complex design.

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 researcher examined whether interrogators who expect a suspect to be guilty,rather than innocent,use more persuasive interrogation techniques.The researcher created a laboratory situation in which students were randomly assigned to actually commit a crime or not commit a crime by following a set of instructions given to them.This is referred to as "Suspect Status." Before student interrogators interviewed a suspect,they were randomly assigned to conditions that led them to believe the suspect was guilty or innocent of the crime.This is referred to as "Interrogator Expectation." Independent observers rated the effort used by interrogators to obtain a confession using a 1-10 rating scale (higher scores indicate greater effort).Suppose the researcher observed the following means for each group: Describe the effects of the independent variables in this experiment (assume any nonzero difference between means indicates a statistically significant effect).

The following table includes the results of a 2 * 2 design in which one independent variable was the gender of a research confederate leading a group discussion (male or female)and the second independent variable was the outcome of the group performance (success or failure).Both variables were manipulated by the experimenter using random groups designs.The dependent variable was participants' rating of the confederate leading the discussion.There is an interaction effect in this experiment.Which of the following statements is appropriate for describing the interaction effect?

A researcher is interested in studying the effectiveness of two different learning strategies A and B,and whether the effects of the learning strategies differ for easy material compared to difficult material.The researcher has 80 participants available.The dependent variable is percentage correct on tests of the material.The researcher hypothesizes that 1 participants will always have higher test scores for easy compared to difficult material,and 2 learning strategy B will be better than learning strategy A for difficult material,but the strategies will produce little difference in test results for easy material. Draw a graph that displays mean results consistent with the researcher's hypothesis.

When each level of one independent variable is combined with each level of a second independent variable,the combination of these two variables is called

.He is also interested in knowing whether high or low test-anxious individuals' performance is different for the computerized version of the two tests compared to the paper-and-pencil version of the tests.Within each anxiety group,he randomly assigns participants to either the computer version or the paper version of the GRE tests.Participants then complete both the verbal and quantitative tests of the GRE in the test version they've been assigned (computer or paper).Thus,each participant has two scores,a Verbal score and a Quantitative score. Assuming equal numbers of participants in each condition,how many individuals will be in each independent groups condition?

.He is also interested in knowing whether high or low test-anxious individuals' performance is different for the computerized version of the two tests compared to the paper-and-pencil version of the tests.Within each anxiety group,he randomly assigns participants to either the computer version or the paper version of the GRE tests.Participants then complete both the verbal and quantitative tests of the GRE in the test version they've been assigned (computer or paper).Thus,each participant has two scores,a Verbal score and a Quantitative score. What is the repeated measures variable? What are the levels?

Use this graph to answer the question that follow: Describe the factorial design in this experiment .