Definitions
Define Control
Most experiments involve two groups of subjects a _____________ group and a __________ group. Fill in the blank.
experimental, control/comparison
True or False. Designs that are "strong" do not have built in controls for threats to internal validity.
False
What is a placebo?
A sugar pill.
Describe the first two components in experimental research.
1. purpose
2. definitions
What is mechanical matching?
The process of pairing two persons whose scores on a particular variable are similar.
What variable is manipulated in the study?
The independent variable.
What is happening in a one-shot case study?
A single group is exposed to a treatment or event and a dependent variable is subsequently observed to assess the effect of the treatment.
A question that a researcher must ask is; How likely is it that any ___________ threat exists in _______ study? Fill in the blanks.
particular, this
Describe parts three and four of experimental research.
3. prior research
4. hypothesis
What is a regressed gain score?
The difference between the predicted and actual score.
What is happening in a one-group pretest-posttest design?
A single group is observed or measured not only after being exposed to a treatment of some sort, but also before.
What is step 1 in evaluating the likelihood of a threat?
Ask what specific factors either are known to effect the dependent variable or may logically be expected to affect this variable?
Describe parts five and six of experimental research.
5. sample
6. instrumentation
Define experimental group.
The group in the study that receives the treatment (method).
What is random selection?
Every member of a population has an equal chance of being selected to be a member of the sample.
What is unique about quasi-experimental design?
This design is unique in that it does not include the use of random assignment.
What is step 2 in evaluating the likelihood of a threat?
Ask what is the likelihood of the comparison groups differing on each of these factors.
Describe parts seven and eight of experimental research.
7. procedures
8. data analysis
Define extraneous variable
A variable that makes possible an alternative explanation of results; an uncontrolled variable.
What are three things that should be noted about random assignment?
1. It takes place before the experiment begins.
2. It is a process of assigning or distributing individuals to groups.
3. It allows the researcher to form groups that are equivalent.
Fill in the blank. Factorial designs extend the number of _________________ that may be examined in an experimental study.
What is step 3 in evaluating the likelihood of a threat?
Evaluate the threats on the basis of how likely they are to have an effect, and plan to control for them.
Describe parts nine and ten of experimental research.
9. results
10. discussion