What is a main effect?
The effect of a dependent variable on an independent variable.
The effect of an independent variable on a dependent variable.
The effect of one independent variable on a dependent variable depending on the level of another independent variable.
What is a one-shot case study?
A pre-experimental design in which a group gets a pretest and a treatment, but no post-test.
An experimental design in which a group gets a treatment and a post-test, but no pretest.
A pre-experimental design in which a randomly assigned group gets a treatment and a post-test, but no pretest.
A pre-experimental design in which a group gets a treatment and a post-test, but no pretest.
Why is a pretest post-test control group design ideal?
Participants are randomly assigned to one of two groups: control or experimental.
A true comparison can be done with a post-test.
You can have more than one experimental group.
All of the above.
What is the coefficient of determination?
A number that signifies the strength in the relationship between two variables.
The amount of variance that is accounted for in one variable by the other variable.
How do you arrive at the coefficient of determination?
Square the r value.
Square the p value.
If you ended up with a coefficient of determination of .12, how would you interpret this number?
There is a small positive correlation between the two variables.
The dependent variable in your study only accounted for 12% of the variance in your independent variable.
The independent variable in your study only accounted for 12% of the variance in your dependent variable.
The independent variable in your study accounted for 88% of the variance in your dependent variable.
What is the coefficient of alienation?
The unexplained variance.
When would you use a Spearman's correlation?
If one or more of your variables is normally distributed.
If one or more of your variables is not normally distributed.
What is an extraneous variable?
A variable other than the dependent variable that may influence the independent variable, which decreases internal validity.
A variable other than the dependent variable that may influence the independent variable, which increases internal validity.
A variable other than the independent variable that may influence the dependent variable, which decreases internal validity.
A variable other than the independent variable that may influence the dependent variable, which increases internal validity.
How would you control for extraneous variables?
Ignore unimportant variables or factors.
Employ three levels of randomization.
Match your samples and make sure they are as homogeneous as possible.
Run an analysis of covariance (ANCOVA) to statistically equalize your groups.
All of these answers are correct.
In a Solomon 4-group design, how many control groups are there?
1
2
3
0
In the Solomon 4-group design, how do Control Group 1 and Control Group 3 differ from one another?
Control Group 1 receives a pretest and treatment, but Control Group 3 only receives a pretest.
Control Group 1 receives a pretest and treatment, but Control Group 3 only receives the treatment.
Control Group 1 receives a pretest but no treatment; Control Group 3 only receives the treatment.
Control Group 1 receives a pretest but no treatment; Control Group 3 receives neither.
Why is it that the pretest is omitted in Control Groups 2 and 3 in a Solomon 4-group design?
Because the pretest may have an unintended consequence on behavior.
Because the pretest is only relevant in the experimental group.
What is a cross-sectional study?
A type of non-experimental research that examines several groups of people at one point in time.
A type of non-experimental research that examines one group of people at one point in time.
A type of non-experimental research that examines several groups of people at more than one point in time.
A type of non-experimental research that examines one group of people at more than one point in time.
Correlational research is non-experimental.
Cross-sectional, longitudinal, and follow-up studies are all considered what type of research?
Historical
Descriptive
Developmental
Correlational
What is a factorial design?
A design with only one independent variable.
A design with more than one independent variable.
If your factorial design looked like this - 2 x 2 x 2 - how many main effects would you have?
8
6
If your factorial design looked like this - 2 x 2 x 2 - how many interactions would you have?
In factorial designs, only main effects need to be tested for statistical significance by ANOVA.
