Generation of output style variation in the SAMMIE dialogue system

A dialogue system can present itself and/or address the user as an active agent by means of linguistic constructions in personal style, or suppress agentivity by using impersonal style. We describe how we generate and control personal and impersonal style variation in the output of SAMMIE, a multimodal in-car dialogue system for an MP3 player. We carried out an experiment to compare subjective evaluation judgments and input style alignment behavior of users interacting with versions of the system generating output in personal vs. impersonal style. Although our results are consistent with earlier findings obtained with simulated systems, the effects are weaker.