Exam (elaborations) PSY550 Final Exam Research Methods

Exam (elaborations) PSY550 Final Exam Research Methods 1. Chuck Wagon is very excited about the within-subjects approach. “Now I’ll never need to run large numbers of subjects again,” he says. However, Chuck has forgotten that within-subjects designs may be a) useless, b) impossible, c) confounded by order effects, or d) impractical when excessive subject time spent in an experiment makes data inaccurate. Give an example of each of these four objections. Answer: 2. Explain the pros and cons of longitudinal, cross-sectional, and sequential designs. Answer: Longitudinal Pros: Shows developmental course, continuity and discontinuity, eliminates cohort. Cons, they are expensive, long, practice effect and selective attribution. Cross-sectional Pros: quick, cheap, demonstrates age difference. Cons; Cohort effect, doesn’t show development process and doesn’t show if its continuous or discontinuous. Sequential Pros; can compare cohorts, not to expensive. Cons: Complicated 3. After watching nursery-school children, Ken Garoo wants to test the hypothesis that some toys are more fun to play with than others. He decides to compare “fun” toys (blocks) with “unfun” toys (stuffed animals). He also wishes to see if there is a sex difference, as well, so sex is added as an independent variable. A) What kind of design is needed? B) Diagram it out. C) Assuming 20 subjects are needed per cell, how many subjects are needed for this study? Answer: (a) (b) (c) 4. Define the term quasi-experiment and discuss the pros and cons of this research method. Answer: Quasi-experimental research makes observations in a study that is structured similar to an experiment, but the conditions and experiences of participants lack some control because the study lacks random assignment, includes a preexisting factor or does not include a comparison/control group. Pros: comparing scores before and after Cons: Lacks comparison /control. 5. Bill Board is “lording” his SAT score over his friend, Rhoda Dendron, who took the ACT. “You only got a 25 in math,” he chortled, “while I got a 300 in math.” Given that the SAT has a μ of 500 and a σ of 100, and the ACT has a μ of 20 and a σ of 5, what is wrong with Bill’s logic (give the answer in both z scores and percentile ranks). Answer: Bill Board's Z-score is: (300 - 500)/100 = -2; whereas Rhoda Dendron's Z-score is: (25 - 20)/5 = 1. So, According to Z-score comparison, Rhonda has actually scored more than Bill. This study source was downloaded by from CourseH on :58:26 GMT -05:00 This study resource was shared via CourseH PSY550 Final Exam Research Methods 6. For each of the following examples, explain whether the researcher has made a correct decision or has made a Type 1 or