On a scatterplot, a correlation coefficient of +1.00 appears as a
a. line that slopes upward to the right
b. horizontal line
c. random array of points
d. vertical line
e. line that slopes downward to the right
In the t-test, the degrees of freedom are a function of
a. the variance
b. the mean difference
c. the sample size
d. the alpha-level
e. the null hypothesis
If a research participant is engaged in a research task and takes it seriously, that study will
a. show acceptable use of the double blind design.
b. have high levels of experimental realism.
c. not result in causal ambiguity.
d. require either random assignment or random selection.
A researcher was interested in the effects of caffeine on memory. After administering various doses of caffeine to participants, she gave participants a test of memory. This is an example of research.
a. correlational
b. post hoc
c. experimental
d. descriptive
e. none of the above
There is a direct correlation between how long you study for a test and how many correct you achieve.
If you changed your measurement to see if there is an association between how long you study and how many errors you make on that test, your analysis would reveal
a. a negative correlation
b. a problem with directionality.
c. a reduced strength of association.
d. no zero order correlation.