Abstract

Effects of response styles and information sources which were predicted differently from the three major theories of group polarization were tested against 112 female college students. Persuasive arguments theory predicts group polarization on private responses, social comparison theory predicts it on public responses, while self-categorization theory argues the polarizing effects on both response styles. According to self­ categorization theory, only ingroup members can induce group polarization, but other two theories do not consider the source effects. It was assumed that response styles and information sources could be affected by the ability of ingroup/outgroup, and we hypothesized that group ability would influence subjects private responses, on the other hand, information sources would affect subjects public responses. The results confirmed these hypotheses. Other results showed that, as predicted, the amount of polarizaton on public responses was bigger than that on private responses and also the amount of polarization produced by an able group was larger than that by an unable group. Based on these results, the nature of intragroup influence was discussed.