  Voice assistants are increasingly prevalent, from personal devices to team
environments. This study explores how voice type and contribution quality
influence human-agent team performance and perceptions of anthropomorphism,
animacy, intelligence, and trustworthiness. By manipulating both, we reveal
mechanisms of perception and clarify ambiguity in previous work. Our results
show that the human resemblance of a voice assistant's voice negatively
interacts with the helpfulness of an agent's contribution to flip its effect on
perceived anthropomorphism and perceived animacy. This means human teammates
interpret the agent's contributions differently depending on its voice. Our
study found no significant effect of voice on perceived intelligence,
trustworthiness, or team performance. We find differences in these measures are
caused by manipulating the helpfulness of an agent. These findings suggest that
function matters more than form when designing agents for high-performing
human-agent teams, but controlling perceptions of anthropomorphism and animacy
can be unpredictable even with high human resemblance.
