The Persuasive Power of Human-Machine Dialogue

The persuasive power of live interaction is hard to match, yet technologies are increasingly taking on social roles to promote behavioral change. We believe that speech-based interfaces offer a compelling mode of interaction for engaging users and are motivated to understand how to best present persuasive information using speech interaction. We present a study comparing the persuasive power of two speech-based systems, a recorded message-based system and an interactive dialogue-based system. Both systems present identical information and differ only in interaction mode. We measure the persuasive power across both conditions using a survival task. We analyze our results using three standard rank correlation methods, and derive a more appropriate method for this task. We show that the difference in apparent persuasion is significant under all measures. Furthermore, the new measure is more powerful (sensitive) than the others on this particular dataset.