TAB 10

#s 1, 2, & 5 (skip #s 3 & 4)

Read #5 as: "explain why post hoc tests are necessary for a study like this."

THINKING ABOUT RESEARCH A summary of a research study in psychology is evidence of social learning. In the current study, given here. As you read the summary, think about the researchers were interested in examining the following questions: whether nonhuman primates show the same level of conformity to peer behavior that humans 1. Is this study an experiment? Explain your show. Study 1 was conducted to examine how answer. often human children, chimpanzees, and orang- 2. Explain why an ANOVA is needed for this utans change their current problem-solving study instead of a t test. strategy after watching peers perform a differ- ent strategy for the problem. Study 2 was con- 3. What factor would have been included in ducted to examine whether the presence and the ANOVA analysis for comparison of the number of peers during the strategy test phase switch-stay scores? would influence the children's strategy-switching 4. How do you know that the one-way ANOVA behavior. was significant in this study? Method of the Study. In this study, 18 children, 5. Explain why these researchers used post 12 chimpanzees, and 12 orangutans partici- hoc tests as part of their analyses. pated. Participants completed a task of dropping balls into one of three slots in boxes presented Research Study. Haun, D. B. M., Rekers, Y., & to them on a display (see Figure 11.9 for a dia- Tomasello, M. (2014). Children conform to the gram of the task]. One of the boxes dispensed behavior of peers; other great apes stick with what a reward (chocolate for children, peanuts for they know. Psychological Science, 25, 2160-2167. animals) when a ball was dropped into its top slot. Participants completed the task until they Note: Study 1 from this article is described next. received the reward on 8 of 10 consecutive trials. They then watched three familiar peers lone at a Purpose of the Study. The study examined social time) perform the task for two trials each using learning behaviors in order to compare human a different box than the one the participant had social learning to social learning in nonhuman used in the initial phase. Peers were rewarded on primates. Past studies le.g., Laland & Galef, both of their trials. Participants were then tested 2009] have shown that, similar to humans, on the task again while the peers watched. They many different animal species show evidence performed three trials in the test phase. Each of of social groups with behavioral differences. In the three trials was recorded as a stay response addition, both humans and animals have shown ( they used their same box from the initial phase], (Continued)[Continued] a switch response (they used the box they had used a different box from both the initial phase seen their peers usel, or an other response [they and their peers]. FIGURE 11.9 _ Task Performed by Participants in the Haun et al. (2014) Study Individual Peer Experience Demonstration Test D1 D2 D3 Source: Haun, Rekers, and Tomasello (20141. Note: P - Participant, D = Demonstration (D1, 02, and Dal. Results of the Study. A switch-stay score was cal- results for the three participant groups. The graph culated for each participant for the three trials they shows that, on average, children switched their performed in the test phase. Positive scores indicate responses to those shown by their peers, whereas more switch responses, and negative scores indicate animals stayed with their original responses, show- more stay responses. Figure 11.10 illustrates the ing less influence of the peer demonstrations.FIGURE 11.10 . Mean Switch-Stay Scores for the Haun et al. (2014) Study 2 1 0 Switch Response - Stay Response -1 -2 -3 Children Chimpanzees Orangutans Source: Haun et al. (2014). Conclusions of the Study. From the results of the From their studies, the researchers concluded that study, the researchers concluded that humans nonhuman primates are not influenced socially by are more willing to adjust their behavior to match peers' behavior as much as humans are. peers' behavior than are nonhuman primates