Persuading Investors: A Video-Based Study

Persuasive communication functions through not only content but also delivery—facial expression, tone of voice, and diction. This paper examines the persuasiveness of delivery in startup pitches. Using machine learning algorithms to process full pitch videos, we quantify persuasion in visual, vocal, and verbal dimensions. We find that positive (i.e., passionate, warm) pitches increase funding probability. However, conditional on funding, startups with higher levels of pitch positivity underperform. Women are more heavily judged on delivery when evaluated in single-gender teams, but they are neglected when copitching in mixed-gender teams. Using an experiment, we show that persuasion delivery works mainly through leading investors to form inaccurate beliefs.