The tone analysis for the debate analyzer is performed by the IBM Watson Tone Analyzer service that is part of the Watson Developer Cloud.  The Tone Analyzer application provides blocks of text to Watson and the level of 13 different tones are returned.  The tones are in three categories: emotion, language, and social tendencies.  The emotion category includes anger, fear, joy, sadness, and disgust.  The language category includes confident, analytical, and tentative.  The social tendencies category includes openness, conscientiousness, extroversion, agreeableness, and emotional range.