Select Questions

Chapter 8

1. Counterbalancing is a technique that can be used for:

balancing order effects.

testing interactions.

dealing with subject factors.

converting a between-subjects design to a within-subjects design.

2. See the summary table below. In the analysis of this two-factor design, __________ F test(s) was/were computed.
Table
Analysis of Variance
Summary Table for Depression Scores
Source              df       F
A = Drug Th         1      1.86
B = Cog Beh Th     1     12.23*
A x B                  1       2.03
Error                30
* p < .05

3. In the two-factor design shown in the summary table below, there was/were __________ level(s) of Factor A, Drug.
Table
Analysis of Variance
Summary Table for Depression Scores
Source              df       F
A = Drug Th         1      1.86
B = Cog Beh Th     1     12.23*
A x B                  1       2.03
Error                30
* p < .05

4. A study contains two factors, X and Y, each with two levels (present, absent). The possible treatments are __________.

X1Y1, + X2Y2

X and Y

X1Y1, + X1Y2, + X2Y1

X1Y1, + X1Y2, + X2Y1, + X2Y2

5. A researcher investigates the influence of illumination levels (high, moderate, low) on reading speed, for texts varying in difficulty (complex, simple). In this factorial design, there are a total of __________ treatments.

6. A researcher investigates the effect of caffeine on problem solving speed. She administers either a placebo, 1, 2, or 5 mg of caffeine to subjects and measures the average time it takes them to solve three problems. This design contains _______________ factor(s) with __________ level(s).

one, four

four, one

one, three

four, three

7. In a within-subjects design, the most likely threat to internal validity is __________.

testing

statistical regression

history

instrumentation

8. When comparing line and bar charts, __________.

both are equally good at displaying study results

tables are better than either the line or bar chart at showing interactions

neither is as good as a table

the line chart is superior to the bar chart at showing interactions

9. The degrees of freedom associated with the main effects and interaction in an analysis of variance depend on:

the context of the experiment.

the power of the statistical test.

the size of the study.

the degree of experimental control that is achieved.

10. A __________ design is a design with two or more independent variables, in which the complete set of treatments is defined by the product of the levels of the independent variables.

factorial

completely randomized

randomized blocks

Latin square

11. When factors such as age and sex, which are based upon characteristics of subjects, are used as a factor in a factorial design, __________.

study results are easy to interpret

it may be because it is not feasible or ethical to manipulate that factor (e.g., stress).

results will probably not generalize

subjects may be assigned in a completely random fashion

12. The design that best controls for individual differences between subjects, using the fewest number of subjects, is the __________.

randomized block design

within-subjects design

completely randomized design

between-subjects design