Question 1. Andrew designed an experiment that controlled extraneous variables so that the effects on the dependent variable could only be attributed to the independent variable. Based on this description, his experiment achieved satisfactory

construct validity.
ecological validity.
external validity.
internal validity.

Question 2. A scientific writing style is parsimonious. This means that the writer

conveys information in as few words as possible.
does not make inferences about what the reader knows.
restricts the number of theoretic constructs discussed in the report.
uses shorter sentences instead of longer ones.

Question 3. The primary purpose of a written research report is

advocacy of a theoretical perspective.
communication of research methodology and findings.
expression of the researcher's opinions regarding a problem area.
stimulation of follow-up studies.

Question 4. You should describe special steps taken to control extraneous variables in the ____ subsection.

apparatus
design
participants
procedure

Question 5. "A t test indicated that attitude scores were significantly different after violent videos than after nonviolent ones, t (34) = 3.12, p < .01, partial η2 = .22" should be placed in the ____ section of a research report.

introduction
method
procedure
results

Question 6. When an experiment is long, subjects may become bored and "go through the motions" until the last experimental condition ends. When this impairs subject performance, it illustrates

carryover effects.
fatigue effects.
interference effects.
practice effects.

Question 7. The advantage of unobtrusive measures is that they

have greater external validity.
reduce confounding.
yield more realistic data.
have greater external validity and yield more realistic data.

Question 8. You should first state specific predictions about the outcome of your study in the ____ section.

discussion
introduction
methods
results

Question 9. An experiment must be ____ to be externally valid.

internal valid
practically significant
replicable
internally valid and replicable

Question 10. Which is a major limitation of field experiments compared with studies conducted in the laboratory?

It is harder to employ unobtrusive measures.
They have less external validity.
We cannot manipulate antecedent conditions.
We often have little or no control over who participates in the experiment.

Question 11. ____ describes the consistency of an effect across past studies and estimates average effect sizes.

Meta-analysis
Multivariate analysis
Power analysis
Regression analysis

Question 12. "The results of the current experiment supported the hypothesis that exposure to violent music videos would produce greater acceptance of violent behavior" belongs in the ____ section.

discussion
introduction
method
results

Question 13. The overall purpose of the discussion section is to

evaluate and interpret the results of your experiment.
explain how you developed the research hypothesis.
review prior research in the area.
summarize the study.

Question 14. When there is a statistically significant difference between two treatment groups, we know

extraneous variables did not confound the study.
random assignment created groups that were identical on the dependent variable before the researcher manipulated the independent variable.
the effect size of the independent variable is very large.
the independent variable produced group differences on the dependent variable that are larger than we would expect due to chance.

Question 15. When we use random assignment in an experiment, we guarantee that

every subject in our sample has an equal chance of being placed in any of the treatment conditions.
every subject in the population has an equal chance of being selected for the experiment.
the treatment groups are identical on potentially confounding extraneous variables.
treatment order is randomized to prevent order effects.

Question 16. A typical abstract for a research report rarely exceeds ___ words.

60
75
125
250

Question 17. A sample's representativeness affects

external validity
statistical power
internal validity
the experimental design

Question 18. A within-subjects design

controls extraneous variables better than random assignment in a between-subjects design.
is less vulnerable to carryover effects than a between-subjects design.
requires less time to run subjects than a between-subjects design.
requires more subjects than a between-subjects design.

Question 19. Which is a good "rule of thumb" for selecting an experimental design?

Select a design based on the number of subjects immediately available.
Select a design that can detect higher-order interactions.
Select the design with the lowest statistical power.
Select the simplest design that will adequately test your hypothesis.

Question 20. Since subjects in a within-subjects design participate in more than one experimental condition and are assessed on the dependent variable after each treatment, this design is also called a ____ design.

between-subjects
factorial
independent groups
repeated-measures

Question 21. Since Andrew only had 3 days to collect experimental data, he obtained a convenience sample of students eating lunch in the cafeteria. Nonprobability sampling worried him because of risk to his experiment's

effect size
external validity
internal validity
statistical power

Question 22. Toby measured blood pressure changes in extreme Type As and extreme Type Bs who were each exposed to three levels of time pressure to complete a difficult puzzle (no time limit, 15 minutes, and 30 minutes). Which experimental design did Toby use?

independent groups
matched groups
mixed design
multiple independent groups

Question 23. A within-subjects design is a poor choice when

participation in one treatment condition will provide subjects too many clues about the next conditions.
subjects vary widely in performance on the dependent variable.
there is a small number of subjects.
we need to control extraneous subject variables.

Question 24. We should suspect contamination by ____ when performance improves as participants become more skillful using the equipment.

carryover effects.
fatigue effects.
interference effects.
practice effects.

Question 25. Shawn's study manipulated music (radio or no radio) and list length (short or long), and measured word recognition. Music and list length were

conditions
elements
factors
levels

Question 26. Experimental designs that study two or more independent variables at the same time are called

factorial designs
multiple levels designs
multiple independent groups designs
univariate designs

Question 27. Which technique manipulates antecedent conditions and observes outcomes in a natural setting?

correlational study
ex post facto
field experiment
quasi-experiment

Question 28. Researchers can use ____ to effectively control reactivity in an experiment.

aggregation
control groups
cover stories
unobtrustive measures

Question 29. The most serious dilemma posed by waiting-list control conditions in medical and psychotherapy research is that

waiting-list controls deny treatment to patients who need it.
waiting-list controls lack the credibility of conventional treatments.
waiting-list controls possess low external validity.
waiting-list controls suffer from high subject mortality.

Question 30. ____ means that we can accurately extend experimental results to other situations.

External validity
Practical significance
Internal validity
Research significance

Question 31. Ashton studied the effect of wearing single-strap and double-strap backpacks on shoulder muscle contraction. He tested the same subjects in both single-strap and double-strap conditions to control individual differences in trapezius muscle activity. This study employed a ____ design.

between-subjects
multiple independent groups
matched groups
within-subjects

Question 32. Whenever subjects in an experiment know they are being observed, they may behave differently than others who are not observed. This problem is called

attribution
experimenter bias
reactivity
social facilitation

Question 33. A sample's representativeness affects

external validity.
statistical power.
internal validity.
the experimental design.