Gazing activities during utterances and silence were analyzed in a face-to-face three party conversation setting in anative language (L1) and in a second language (L2). The function of each utterance was categorized according to the GroundingActs defined by Traum (Traum, 1994) so that gazes during utterances could be analyzed from the viewpoint of grounding incommunication (Clark, 1996). Factor analyses of gaze activities showed similar factor structures in L1 and L2 conversations:the first factor was characterized by speakers’ gazes and gazes during silence, and another factor was characterized by listeners’gazes in each condition. Analyses of the participants based on the factor scores, however, showed different tendencies betweenthe two conditions, suggesting that language proficiency affects gaze activities during utterances.

Although many studies have analyzed the communicative functions of gaze, it is still unclear how linguistic proficiency and communication contexts affect gazing activities. Quantitative analyses of speaker’s and listener’s gaze were conducted taking the factors of grounding in communication, conversation topic, and linguistic proficiency into consideration. The results showed that the duration of a listener’s gaze is much longer during utterances that convey new information while the duration of a speaker’s gaze did not show much difference, suggesting that the characteristics of the grounding act factor affect a listener’s gazing activities but not those of the speaker. We also observed that linguistic proficiency and conversation topic have a much greater effect on the listener’s gaze. The results will contribute to multi-party interaction studies that examine the effect of linguistic proficiency, and provide valuable information that could assist in the design of interaction support systems for users with different linguistic proficiency.