An advantage of holding a variable constant rather than using random assignment to form your groups is that holding a variable constant ____.
a. reduces error due to participant differences
b. is easier than randomization
c. prevents confounding
d. ensures a nonbiased sample
The Ethics Committee of the APA educates _________ about ethical issues related to psychological research.
a. psychologists
b. the public
c. students
d. all of these
When systematic error affects the mean of a distribution, it is referred to as ____.
a. shifting
b. variance
c. bias
d. regression
When using the Wilcoxon tests, the obtained value must be ______ the critical value in order to establish statistical significance.
a. less than or equal to
b. greater than or equal to
c. greater than
d. equal to
Because random assignment is likely to create groups of different sizes, researchers often employ ____.
a. restricted random assignment
b. matched random assignment
c. simple random assignment
d. sampling
If you could see all random error in a distribution, it would ____.
a. have a variance equal to the mean
b. sum to zero
c. shift the mean in a positive direction
d. be greater than the population variance
An ethical psychologist
a. mistreats animal participants.
b. submits animal participants to undue harm.
c. ensures that all individuals using animals under their supervision have been instructed in the care of animals.
d. is not required to have specific training in the care and use of animal subjects.
Why is random assignment used in between-subjects experimental designs?
a. to hold participant characteristics constant
b. to ensure a nonbiased sample
c. to ensure anonymity of the research participants
d. to eliminate systematic differences between the groups
The Wilcoxon tests are used with _____ data.
a. ordinal
b. interval
c. ratio
d. nominal
Combining multiple independent measures to get at a more accurate estimate of a variable is referred to as ____.
a. triangulation
b. covariation
c. validation
d. imputation