“…In [16], it was reported that increases in pitch and intensity, as well as certain POS patterns, are key back-channel-inviting cues in taskoriented dialog. The multi-lingual comparison discussed in [5,6,7] found that pitch patterns, e.g., periods of low pitch or drops in pitch, are positively associated with listener back-channels in Japanese-, English-, Arabic-and Spanish-speakers. Recently, [17] investigated cultural differences in gaze, proxemics, and back-channel behavior in a multi-modal corpus of American English, Mexican Spanish, and Arabic speakers.…”