1. Find an article to critique. If you are having trouble finding an article, consult Web Appendix B (Searching the Literature) or critique the article in Appendix B. To critique the article, question its internal, external, and construct validity. If you want more specific help about what questions to ask of a study, consult Appendix C.
1. To find an article, you could
a. Use the article in Appendix B (pages 652-664 of your text).
b. Find a summary of an article by browsing by topic using APA PsycNet (you will need either to go to your library or pay APA to get the actual article).
c. Use Google Scholar. For tips on how to find recent articles and how to actual articles, review Google Scholar's search tips.
d. If you want more help on finding an article, click here.
2. To critique the article, consider the four validities and the main threats to those validities.
Validity Threat Methods/Design That Reduce the Threat Internal validity Failure to randomly assign participants to condition Randomized experiment Construct validity Poor measures
Valid measuresValid manipulations and manipulation checks
Research realism and blind techniques
Blind techniques and objective measures
External validity Participants belonging to one narrow group; many groups not represented or under-represented
Non-random sample of participants
High drop out rate
Unusually high or low amounts of the treatment
Broad range of participants
Low dropout rate
Natural setting, setting is similar to real life in key respects, or high degree of experimental realism
Realistic amounts of the treatment variable
Statistical validity Lack of power to find differences
"Fishing for results" (risking a Type 1 error) by doing many statistical tests
Many participants, reliable measures, standardized procedures, sensitive measures
Meeting assumptions of test, only doing analyses that test hypotheses that were specified in advance, using a traditional significance level
2. What are the main strengths and weaknesses of the study you critiqued?
No set answer, but consulting the table above should help you answer this question. You may also want to consult this web page.
3. Design a direct replication of the study you critiqued. Do you think your replication would yield the same results as the original? Why or why not?
No set answer, but you should justify your answer by referring to the points made on pages 128-131.
4. Design a systematic replication based on the study you critiqued. Describe your study. Why is your systematic replication an improvement over the original study?
No set answer, but you can base your answer on the points made in Boxes 4.3 (p. 135) and 4.4 (p. 136).
5. Design a conceptual replication based on the study you critiqued. Describe your study. Why is your conceptual replication an improvement over the original study?
No set answer, but consulting Box 4.5 (p. 137) should help you answer that question.
6. Evaluate the conclusions of these studies. Then, recommend changes to the study.
a. A study asked teens whether they had taken a virginity pledge and found that those who claimed to have taken a pledge were more likely to abstain from sex than those who claimed not to have taken that pledge. The researchers conclude that abstinence pledges cause students to abstain from sex.
1. The teens who decide to take a virginity pledge may differ from those who choose not to take such a pledge.
2. Teens who kept their pledge may be more likely to remember that they made such a pledge than teens who did not keep their pledge.
3. Teens who made a pledge may state that they kept their pledge even though they did not keep their pledge.
b. A study finds that teens, after completing a three-year, voluntary, after-school abstinence education program, are better informed about the diseases that may result from sex. The researchers conclude that abstinence pledges cause students to abstain from sex.
1. During a three-year period, even without a program, teens could have learned something about diseases that may result from sex during those three years.
2. The teens may be better informed, but that does not mean they were more likely to abstain from sex.
3. If teens in the program were more likely to abstain from sex, that abstinence might be due to the three-year after-school program rather than the pledge.
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