Science of PsychologyEC #1

Methods of Psychological Research

FOR EXTRA CREDIT ANSWER ONLY QUESTIONS 4 & 5 in writing. An answer key for Questions 1-3 is posted on-line on courseworks.

What you will learn: Distinguish between experimental and correlational designs Distinguish between dependent and independent variables Understand some of the challenges faced by researchers in designing a study

Psychologists use a variety of methods to investigate questions related to human behavior. One of the first decisions that psychology researchers must make is how to study their target behavior. For the exercise below we will be concerned with two general methods that researchers use – correlational methods and experimental methods.

Correlational methods involve studying behaviors as they are. These approaches involve careful observation, measurement and interpretation of behaviors to uncover relationships among the factors that influence behavior. In contrast, experimental methods involve procedures that manipulate the conditions surrounding the behavior being studied. By establishing equivalent conditions and systematically varying a specific factor, the experimenter determines the impact of that factor. This is the chief advantage of experimentation; experimental methods allow us to determine cause-effect relationships in a way that correlational methods cannot.

First, try 3 PRACTICE QUESTIONS – No need to answer these formally, though you may want to jot down some notes and check your answers against the on-line answer key. For these questions, you will read about several (hypothetical) investigations. For each situation, consider the following questions:

a) What is the central question in this example?b) Is this an experimental or a correlational design?

If it is an experimental design, what is the independent variable? what is the dependent variable? If it is a correlational design, what variables are being related to one another?

c) Do you see any flaws in the way the question is investigated? These may be problems with factors that are not controlled or even ethical concerns. If you identify flaws, can you think of any way the researcher could have improved the investigation?

1. A group of social scientists reviews all of the case-files from the year 2003 in the department of child social welfare in Fake City, USA (with the names removed). The scientists want to learn about the backgrounds of children who have been assigned to foster care. One of their findings is that the majority of children who receive foster care have experienced physical punishment methods in their prior homes that would be severe enough to qualify as abusive. (Remember, this study is made-up for this homework assignment. This is not a real finding.)

2. Charlie is trying hard to lose his “spare tire” before his wedding. He has two months to get ready for the event. He decides to go about his weight loss systematically, trying out a new weight loss regimen each week. He hopes to lose weight for the wedding and to determine the best weight-loss method. The first week, Charlie exercises vigorously. The second week, he gives up meat. The third week he drinks large amounts of water. The fourth week, he eats just bananas. He continues to vary his approach each week. At the end of eight weeks, he concludes that his best weight loss comes from exercise.

Science of PsychologyEC #1

3. A physician is intrigued by a new medication that has been developed for sleep disturbance, but he is concerned about its expense relative to the medication he usually prescribes. He decides to evaluate the success of the medication. He determines that the next 20 patients who complain of sleep problems will help him establish the effectiveness of the medication. Once he identifies the complaint, the physician slips out of the room and tosses a coin. If it comes up “ heads,” he prescribes the new medication. If it comes up “tails,” he prescribes the medication he previously prescribed. He continues this procedure until he has 10 patients in each condition. At the end of a three-month period, he asks his patients to report the degree of improvement on a ten-point scale. He discovers that the new medication provides no real advantage over the4 older, less expensive medication.

EXTRA CREDIT ASSIGNMENT #1 – Experimental Methods

Please type your response to questions 4 and 5 for extra credit assignment #1. You can submit in class or on-line (see Extra Credit Instruction available on-line in the assignments section.) On-line submission is preferred.

Now it’s your turn to be a researcher. Here are two research questions. How would you address them?

4. In old movies and cartoons, you could always tell the bad guys from the good guys by the color of their hats. The bad guys wore black and the good guys wore white. The association of black with “bad” and white with “good” has an extensive history within our culture. Frank and Gilovich (1988) noted this association and wondered whether the color of the uniform of a sports team would influence the aggressiveness of that team’s members. Frank and Gilovich hypothesized that teams whose players wear black uniforms would be more likely to behave aggressively in sporting events than teams whose players wear lighter colors. Frank and Gilovich (1988) used a variety of techniques to investigate this hypothesis.

How would you research this question?

Assess your approach using questions (b) and (c) listed above.

5. A new popular movie depicts a grisly scene of teen violence against senior citizens. Although the criminals in the movie are caught and punished, city officials are dismayed to discover that similar acts of violence increase across the city shortly after the movie opens. A reporter wants to determine whether this film leads to an overall increase in violent acts against senior citizens.

If you were the reporter, how would you address this question?

Assess your approach using questions (b) and (c) listed above.

This exercise is adapted from Jane Haldonen and Cynthia Gray’s book, “The Critical Thinking Companion for Introductory Psychology”