of the Thesis Individuals Differences in Social Facilitationby Lyra M. Stein Thesis director: Dr. John R. AielloThe present study sought to elucidate the differences in performance in a social facilitation paradigm based on Uziel's (2007) meta-analysis. The present study measured the personality variables of anxiety, extraversion and self-esteem to determine moderation of performance on two word-pair tasks of varying complexity in a social facilitation paradigm. One hundred thirty-eight participants were randomly assigned to either the absence (alone) or presence (observer present) conditions. The results indicate that there are significant differences in performance based on differences in anxiety, extraversion and self-esteem, however in a manner other than theorized by Uziel or proposed by the present study. Individuals scoring high on extraversion and self-esteem were facilitated in the absence condition compared with the presence condition.Individuals high in anxiety did not change in performance between the absence and presence conditions. The results are discussed in terms of attentional mechanisms proposed by the distraction-conflict theory of social facilitation.iii Tables &Figures………………………………………………………………….iv