Abstract

This study was to examine the overhearer's effect in referential communication. In the first experiment, we examined whether director's performance was affected by overhear's presence itself. We examined triples of people in which one person told another person in conversation how to arrange 12 complex figures while an overhearer tries to arrange them too. All three began as strangers with the same background information. As predicted, addressees were more accurate at arranging the figures than overhearers although the two shared the same information. The result showed that addressees in the nonexistence condition spend more time and made longer sentences than the existence condition. The second experiment was about the familiarity effect. Two alternative hypothesis was tested. The first hypothesis. "familiarity maintenance hypothesis" assumes that if the overhearer is familiar with the director, the director will use more words to help the overhearer. The alternative hypothesis, "common ground sharing hypothesis", assumes that the director will show no difference in both condition. The result indicated that the performance showed no difference between the two conditions, so the common ground sharing hypothesis was supported. The effect of overhearer's existence and the commonground sharing hypothesis showed that even the same information was provided. active participant(addressees) perfomance was better than passive participant(overhearer). It implies that to be successful communication, active collaboration was needed in addition to the appropriate information.