Chapter 18, Problem 8P

8. In problem 13 in Chapter 9, wepresented a study examining the spotlight effect which refers to overestimatingtheextent to whichothersnoticeyour appearance or behavior, especially when youcommit a social faux pas. Effectively, you feel as if youaresuddenlystandinginaspotlightwith everyone looking.Gilovich,Medvec,andSavitsky (2000)asked college studentsto put on a Barry ManilowT-. Shirtthatfellow students had previously·judged tobe embarrassing. The participants were then led into a room in which other students were already partici­ patinginanexperiment.Later,eachparticipantwas asked to estimate how many people in the room had noticed the shirt and the individuals in the room were also asked whether they noticed the shirt. If 15 out of 20participantsoverestimatedthenumberwhonoticedthe shirt, is this enough to be significantly more than chance? Use a two-tailed test with a = .05.

1. The spotlight effect refers lo overestimating the extent to which others notice your appearance or behavior, especially when you commit a socia1 faux pas. Effect­ tively, you feel as if you are suddenly standing in a spotlight with everyone looking. In one demonstration of this phenomenon. Gilovich, Medvec, and Savitsky (2000) asked college students to put on a Barry Manilow T-shirt that fellow students had previously judged to be embarrassing. The participants were then led into a room in which other students were already participating in an experiment. After a few minutes the participant was led back out of the room and was a11owed to remove the shirt. Later, each participant was asked to estimate how many people in the room had noticed the shirt. The individuals who were in the room were also asked whether they noticed the shirt. In the study the participant significantly overestimated the actual number of people who hadnoticed.

In a similar study using a sample of n = 9 participants, the individuals who wore the shirt produced an average estimate of M = 6.4 with SS = 162. Theaveragenumberwhosaidthey noticed was 3.1. Is the estimate from the participants significantly different from the actual number? Test the null hypothesis that the true mean is µ = 3.1 using a two-tailed test with a = .05.

Is the estimate from the participants significantly higher than the actual number (µ = 3.1)? Use a one-tailed test with a = .05.