Chapter 11, Problem 13P

Research results indicate that physically attractive people are also perceived as being more intelligent (Eagly, Ashmore, Makhijani, & Longo, 1991). As a demonstration of this phenomenon, a researcher obtained a set of 10 photographs, 5 showing men who were judged to be attractive and 5 showing men who were judged to be unattractive. The photographs were shown to a sample of $n=25$ college students and the students were asked to rate the intelligence of the person in the photo on a scale from 1 to 10. For each student, the researcher determined the average rating for the 5 attractive photos and the average for the 5 unattractive photos, and then computed the difference between the two scores. For the entire sample, the average difference was $M_b=2.7$ (attractive photos rated higher) with $s=2.00$ . Are the data sufficient to conclude that there was a significant difference in perceived intelligence for the two sets of photos? Use a two tailed test with $\alpha =.05$ .