Social signals, their function, and automatic analysis: a survey.

Alessandro Vinciarelli Maja Pantic Hervé Bourlard Alex Pentland Social signals, their function, and automatic analysis: a survey. 61-68 2008 ICMI http://doi.acm.org/10.1145/1452392.1452405 conf/icmi/2008 db/conf/icmi/icmi2008.html#VinciarelliPBP08