“…Sensing affect related states, including interest, confusion, or frustration, and adapting behavior accordingly, is one of the key capabilities of humans; consequently, simulating such abilities in technical systems through signal processing and machine learning techniques is believed to improve human-computer interaction in general (Schuller & Weninger, 2012) and computer based learning in particular (Aist, Kort, Reilly, Mostow, & Picard, 2002;Forbes-Riley & Litman, 2010). Important abilities of affective tutors or lecturers, besides emotional expressivity (Huang, Kuo, Chang, & Heh, 2004), include the choice of appropriate wording, which has been found to be highly important in computer based tutoring to support the learning outcome (Narciss & Huth, 2004).…”