Speakers often come to use similar words during conversation; that is, they come to exhibit lexical similarity. The extent to which this occurs is associated with many positive social outcomes. However, existing measures of lexical similarity are either highly labor intensive or too coarse in their temporal resolution. This limits the ability of researchers to study lexical similarity as it unfolds over the course of a conversation. We present a fully automated metric for tracking lexical similarity over time, and demonstrate it on individual conversations, explore general trends in aggregate conversational dynamics, and examine differences in how similarity tracks over time in groups with differing social outcomes.

Nonverbal, paralinguistic cues such as punctuation and emoticons are believed to be one of the mechanisms through which interpersonal relationship development takes place in text-based interactions. We use a novel experimental apparatus to manipulate these cues in a live Instant Message conversation. Results show a positive causal relationship of conversation duration and cue use on perceived affinity, and the relationship is contingent upon whether or not partners are able to see each other's cues. Further analysis of the dialogue reveals that reciprocity may play a central role in supporting this effect. We then demonstrate how one's cue use is influenced by a partner's cue use, and show that cues are often used in greeting and sign-off rituals.

Providing the initiator of a conversation with awareness information about their target's availability can improve interruption timing. Providing this information, however, can be particularly challenging with mobile devices, which are carried by users in a range contexts and have limited audible and visual display possibilities due to possible background noise and small screen size. Haptic or tactile displays present a potentially useful alternative, as interaction with mobile devices is often by touch. This paper reports on a dual-task comparison of awareness information usage on a mobile variable-friction tactile display vs. a visual display under conditions that varied in task type and task workload. Participants using the tactile display performed marginally better on the primary task, but were less accurate and slower on the awareness task. However, there is evidence that some of the awareness task differences dissipated over time. Self-report data also suggests that people's experience with the tactile display was generally positive and improved over time.