Page 1 of 6 ID# Exam 2 PS 217, Spring 2011 As always, the Skidmore Honor Code is in effect. At the end of the exam, I have a sheet on which you will attest to your adherence to the Honor Code. Read each question carefully and answer completely, showing all your work. Good Luck! 1a. In each of the chapters we’ve covered for this exam, there has been some discussion of effect size. First of all, tell me how you would measure effect size (i.e., tell me the statistic you would use). Then, tell me how effect size and power are related. [3 pts] 1b. If researchers work to achieve a level of power of .80, what does that say about their tolerance for Type II Error relative to Type I Error, given the usual α-level used in research? [2 pts]Page 2 of 6 2. Dr. Rick Call is interested in whether the type of mood reflected by a word (happy, neutral, or sad) affects how well the word is remembered. He constructs a list of 18 words: 6 happy words (e.g., joyful, bright), 6 neutral words (e.g., derive, convey), and 6 sad words (e.g., gloomy, lonely). He then presents the list repeatedly to 30 participants until they can recite the entire list correctly twice in a row. One week later, each participant attempts to recall the entire list. The number of items correctly recalled as a function of the type of word is analyzed. If you were Dr. Call’s research assistant, how might you suggest that he construct the list of words? [3 pts] Complete the source table below and interpret the results of this study as completely as you can. [12 pts] Source Type III Sum of Squares df Mean Square F Sig. Partial Eta Squared Observed Powera Emotion Sphericity Assumed 86.67 .000 .634 1.000 Error(Emotion) Sphericity Assumed 50.00Page 3 of 6 3. Eskine, et al. (2011) recently published an article in Psychological Science with the intriguing title “A bad taste in the mouth: Gustatory disgust influences moral judgment.” Their abstract reads, in part… Can sweet-tasting substances trigger kind, favorable judgments about other people? What about substances that are disgusting and bitter? Various studies have linked physical disgust to moral disgust, but despite the rich and sometimes striking findings these studies have yielded, no research has explored morality in conjunction with taste, which can vary greatly and may differentially affect cognition. The research reported here tested the effects of taste perception on moral judgments. After consuming a sweet beverage, a bitter beverage, or water, participants rated a variety of moral transgressions. From their method section: [Participants] were told that we were exploring the effects of motor interference (specifically arm-hand movements) on cognitive processing, and we therefore directed them to drink a beverage during a moral-judgment task to instantiate this movement in a natural way. Participants in the sweet condition were given Minute Maid Berry Punch, those in the bitter condition received Swedish Bitters, and control participants were given water. They were not told the identity of the beverages, although an ingredient list was provided so they could check for potential allergens. Beverages were administered in two 1-teaspoon doses in a small cup; the first dose was given at the onset of the moral-judgment task, and the second one was administered at the halfway point to ensure that the taste lingered throughout the task. Participants were instructed to drink each dose in its entirety in a single swift motion, “as if you were drinking a shot.” Moral judgments were assessed using Wheatley and Haidt’s (2005) moral vignettes, which portray various moral transgressions (second cousins engaging in consensual incest, a man eating his already-dead dog, a congressman accepting bribes, a lawyer prowling hospitals for victims, a person shoplifting, and a student stealing library books). All participants received the same six moral vignettes, in counterbalanced order. After each vignette, participants rated “how morally wrong” the offense was on a scale consisting of a 14-cm line representing a continuum from not at all morally wrong to extremely morally wrong. Participants were asked to make a slash at the point on the continuum corresponding to their impressions. These marks were then converted to scores ranging from 0 to 100, with higher scores indicating harsher moral judgments. Complete the source table below. In light of their hypotheses, interpret the results as completely as you can (as you might in a discussion). [15 pts]Page 4 of 6 ANOVA Moral Sum of Squares df Mean Square F Sig. Between Groups 10.27 .000 Within Groups 174.03 Total 4. Generally speaking, what does a post hoc test (such as Tukey's HSD) do for you? You should know, of course, that it allows you to compare two means to determine if they are drawn from populations with different means. But you could test such a hypothesis with a t-test or an ANOVA. So, what does a post hoc test do for you beyond allowing you to test for the difference between two conditions? [5 pts]Page 5 of 6 5. A psychologist would like to examine the relative effectiveness of three therapy techniques for treating mild phobias. A group of 15 individuals who display a moderate fear of spiders is obtained. These individuals are randomly assigned to one of the three therapies with n = 5. The dependent variable is a measure of the reported fear of spiders, with higher numbers indicating greater fear. Analyze these data as completely as you can. [20 pts] Therapy A Therapy B Therapy C 8 3 1 5 3 0 5 0 1 7 2 2 5 2 1 (ΣX) or T 30 10 5 45 ΣX2 188 26 7 221 SS 8 6 2Page 6 of 6 6. Two researchers were interested in studying the effects of reward magnitude (the IV) on performance. Both researchers used the same independent variable, with three levels of reward magnitudes ($1, $5, $20). They used the same pool of introductory psychology students as participants, the same total number of participants (24), the same apparatus, the same task, and the same performance measure (DV). One researcher used an independent groups design and the other researcher used a repeated measures design. Assume that neither study has a major flaw (e.g., repeated measures design is properly counterbalanced, random assignment to conditions). In each case, the researchers used α = .05. Complete the source tables for the two experimenters seen