  Humanness is core to speech interface design. Yet little is known about how
users conceptualise perceptions of humanness and how people define their
interaction with speech interfaces through this. To map these perceptions n=21
participants held dialogues with a human and two speech interface based
intelligent personal assistants, and then reflected and compared their
experiences using the repertory grid technique. Analysis of the constructs show
that perceptions of humanness are multidimensional, focusing on eight key
themes: partner knowledge set, interpersonal connection, linguistic content,
partner performance and capabilities, conversational interaction, partner
identity and role, vocal qualities and behavioral affordances. Through these
themes, it is clear that users define the capabilities of speech interfaces
differently to humans, seeing them as more formal, fact based, impersonal and
less authentic. Based on the findings, we discuss how the themes help to
scaffold, categorise and target research and design efforts, considering the
appropriateness of emulating humanness.
