Humble Voices in Political Communication: A Speech Analysis Across Two Cultures

Classical works on affective and persuasive computing have pointed out that technologies whose goal is to influence the user’s need to communicate in a charismatic or dominant style, neglecting the potential persuasive strength of other styles, such as a humble style. Humility can be defined as an epistemic and interactional stance aimed at communicating the person’s attitude towards an object, topic, or the interlocutor. Previous studies on persuasion in politics conducted multimodal analyses to identify those postures, prosodic features, gaze patterns, and facial expressions that convey humility. In this study, we describe the features of humility associated with a speaker's tone-of-voice, by comparing two pairs of popular politicians from Usa (Obama vs Trump) and Italy (Gentiloni vs Salvini) during TV interviews. Results on the acoustic side point out clear differences in the speech characteristics of humble vs. dominant politicians: Gentiloni’s and Obama’s speech is characterized by short utterances, more hesitations and disfluencies and fewer stressed words. The two speakers' loudness levels are lower, and their voice qualities either more sonorant or even breathier. We discuss our results with respect to their implications for persuasive processes which can be associated not only to the speakers’ features but also to the speaker-audience personality-trait matching.