Social and Emotional Characteristics of Speech-based In-Vehicle Information Systems Impact on Attitude and Driving Behaviour

Abstract: Modern vehicles use advanced information systems in vehicles to provide and control a wide variety of functions and features. Even modest vehicles today are equipped with systems that control diverse functions from air-conditioning to high quality audio/video systems.Since driving requires the use of eyes and hands, voice interaction has become more widely used by in-vehicle systems. Due to the technical complexity involved in voice recognition, focus has been on issues of speech ecognition. Speech generation is comparatively simple, but what effect does the choice of voice have on the driver? We know from human-human interaction that social cues of the voice itself influence attitude and interpretation of information. Introducing speech based communication with the car changes the relationship between driver and vehicle. So, for in-vehicle information systems, does the spoken voice matter?The work presented in this thesis studies the effects of the voice used by invehicle systems. A series of studies were used to answer the following questions: Do the characteristics of voices used by an in-vehicle system affect driver’s attitude? Do the characteristics of voice used by an in-vehicle system affect driver’s performance? Are social reactions to voice communication the same in the car environment as in the office environment?Results show that voices do matter! Voices trigger social and emotional effects that impact both attitude and driving performance. Moreover, there is not one effective voice that works for all drivers. Therefore an in-vehicle system that knows its driver and possibly adapts to its driver can be the most effective. Finally, an interesting observation from these studies is that social reactions to voice communication in the car are different than in the office, Similarity attraction, an otherwise solid finding in social science, did not hold all studies. It is hypothesized that this difference can be related to the different kinds of task demands when driving a car or working in an office environment.