What's Wrong With These Studies?

What is wrong with Marcie and Sean's report? Explain it here. Answer

Study #2:

Ani has long been interested in dating relationships. One issue that she has wondered about was whether the length of a couple's courtship affects how happy the couple is in their marriage. She decides to carry out a brief research project to examine this issue.

She randomly selects ten married couples to participate. She independently asks each partner in each couple to answer two questions: First, how long did they date prior to their marriage, and second, on a scale of 1 to 10, how happy are they in their marriage.

After collecting and analyzing her data, she concludes that people who date each other for long periods of time prior to their marriage, are happier in their marriage. Thus, longer periods of courtship cause happier marriages."

Is Ani's conclusion correct? Write your thoughts here. Answer Study #3:

Antonio has just completed a paper for his introductory psychology course. His work is based on his personal account of a high school classmate and friend of his that was recently convicted in a serial murder case. His paper is a biographical account of this person's early youth and adolescence and the factors during these times that may have contributed to his killing sprees. Near the end of his paper, Antonio concludes, "Thus factors such as these, which occur during a person's early youth and teenage years, seem to play a major role in contributing to people becoming serial murderers.

Is Antonio's statement correct?. Answer

Study #4:

Dr. Lizzie Taylor is a psychopharmacologist who believes that she has developed a safe drug to enhance memory. To test her new drug, she gives a single dose of the compound to each of 15 volunteers. She allows the drug 30 minutes to take effect prior to asking her subjects to memorize a list of 50 Hebrew nouns. She then records how many nouns each subject memorized correctly. She finds that all of her subjects correctly recalled about 75 percent of the nouns. She concludes that her drug did indeed enhance their memories. (To her credit, Dr. Taylor made sure that her subjects were of average intelligence, were taking no other drugs or medications immediately prior to her study, and were not familiar with the Hebrew language.)

Is Dr. Taylor's conclusion justified by her experimental procedure? Answer

Study #5:

Suppose that you are a graduate teaching assistant (GTA) for an introductory psychology class. The class instructor has assigned each student in the course to write a brief research proposal that outlines an experiment that he or she would like to conduct. Just before the project is due, a student, Lindy, approaches you and asks you for suggestions regarding his proposal.

He proposes a study in which two groups of subjects will be tested for reaction time to stopping a vehicle in response to red lights. (He is proposing to use a driving simulator in which subjects would sit and watch a display screen. Occasionally, a red light will appear on the screen. The subject's task is to step on the brake pedal as fast as possible in response to seeing the red light. The reaction time is the time between the subject seeing the red light and stepping on the brake pedal.) One group of subjects, the experimental group, will be given a moderate dose of alcohol 30 minutes prior to being tested in the simulator. The other group, the control group, will be given a placebo (in this case, a substance which looks, tastes, and smells like an alcoholic beverage, but is nonalcoholic) 30 minutes prior to being tested in the simulator.

You point out to him that this is an interesting study, but that he has overlooked several variables that might confound it and should therefore be controlled for. What are some of the confounding variables that you pointed out, and what suggestions did you offer for controlling these variables?

Your thoughts here. Answer