Question

Aronson and Mills (1959) conducted an experiment to see whether people’s liking for a group is influenced by the severity of initiation. They reasoned that when people willingly undergo a severe initiation to become members of a group, they are motivated to think that the group membership must be worthwhile. Otherwise, they would experience cognitive dissonance: Why put up with severe initiation for the sake of a group membership that is worthless? In their experiment, participants were randomly assigned to one of three treatment groups:

*Group 1 (control) had no initiation.

            *Group 2 (mild) had a mildly embarrassing initiation (reading words related to sex out loud).

            *Group 3 (severe) had a severely embarrassing initiation (reading sexually explicit words and obscene words out loud).

            After the initiation, each person listened to a standard tape-recorded discussion among the group that they would now supposedly be invited to join; this was made to be as dull and banal as possible. Then, they were asked to rate how interesting they though the discussion was. The researchers expected that people who had undergone the most embarrassing initiation would evaluate the discussion most positively. In the table below, a higher score represents a more positive evaluation.

            a. Were the researchers’ predictions upheld? In simple language, what was found?

            b. Calculate the effect size for each of these three t ratios and interpret these.

Answer 1