1. A well-controlled study does all of the following EXCEPT:
2. Researchers interested in the effects of rehearsal on memory selected subjects in the rehearsal group based upon their ability to memorize a list of 20 words in no fewer than four tries. Those who could not do this were dropped from the rehearsal group. Subjects who were assigned to the control group had no similar requirement. Based upon your consideration of the researchers' procedure, what threat to internal validity would be of concern to you?
3. The method of difference differs from the method of concomitant variation in that the former:
4. The potential problem of __________ is to between-subjects design as the potential problem of __________ is to within-subjects designs.
5. A(n) __________ design is a between-subjects design in which one group of subjects receives the treatment (the experimental group) and another group of subjects does not (control group).
6. A(n) __________ is a classification or measure of the properties of people, animals, objects, or events.
7. Scores on an intelligence test would be an example of a ________ variable.
8. The Seattle Longitudinal Study on Aging assessed the intellectual development of adults over a 14 year period. Many subjects, who were tested in the beginning of the study, were not available for follow-up testing. This subject loss is referred to as __________.
9. A researcher tested the hypothesis that Ritalin helps control the distracted behavior of children with ADHD (attention deficit hyperactivity disorder). She randomly assigned half of the children to a group receiving Ritalin and the other half to a group receiving a placebo. She had classroom observers record the frequency of distracted behaviors for each group. The observers were unaware of the experimental groups for each child observed. This study used a __________ design.
10. Results that cannot be generalized to subjects, settings, and measures other than those used in the original research lack:
11. __________ refers to any effects of taking a test on the scores of a second testing.
12. The threat to internal validity of history differs from the threat of maturation because the uncontrolled variables in the former occur:
