How Familiarity Influences the Frequency, Temporal Dynamics and Acoustics of Laughter

Laughter is an affective and social signal that serves many functions. Similar to other social affective signals, laughter production and perception is at least partially context dependent. Familiarity of conversation partners has been shown to be a contextual influence on laughter production. However, the literature is still scarce and divided on how this complex interaction between familiarity and laughter works. Our goal with this paper is to further study this interaction using a newly acquired and annotated corpus and contrast our findings with existing findings in a comprehensive overview of the literature. Using a series of Linear Mixed-Effect Models, we studied if familiarity with the conversational partner and the sex of same-sex conversation pairs affect the laughter frequency, co-laughter frequency or laughter acoustics produced by the subjects in the corpus. The model outputs show that the frequency of laughter and co-laughter is not influenced by familiarity or the sex of conversation pairs. Interestingly, the percentage of co-laughs is significantly influenced by familiarity. Laughter voicedness is influenced by both the familiarity and sex of conversation pairs, where duration of laughter is only influenced by familiarity of the conversation pair. We conclude that familiarity of conversation pairs play an important role in laughter production during interactions and should be systematically explored. Furthermore we make several suggestions for improving the methods in future work.