  A growing literature on speech interruptions describes how people interrupt
one another with speech, but these behaviours have not yet been implemented in
the design of artificial agents which interrupt. Perceptions of a prototype
proactive speech agent which adapts its speech to both urgency and to the
difficulty of the ongoing task it interrupts are compared against perceptions
of a static proactive agent which does not. The study hypothesises that
adaptive proactive speech modelled on human speech interruptions will lead to
partner models which consider the proactive agent as a stronger conversational
partner than a static agent, and that interruptions initiated by an adaptive
agent will be judged as better timed and more appropriately asked. These
hypotheses are all rejected however, as quantitative analysis reveals that
participants view the adaptive agent as a poorer dialogue partner than the
static agent and as less appropriate in the style it interrupts. Qualitative
analysis sheds light on the source of this surprising finding, as participants
see the adaptive agent as less socially appropriate and as less consistent in
its interactions than the static agent.
