"Hi Alex" or "Dear Dr. Morgan"?: Exploring How AI-suggested Politeness Strategies Influence Email Writing and Social Perception Among Native and Non-native Speakers

As AI writing assistants are increasingly used for interpersonal communication, they may have profound impacts on interpersonal relationships. Politeness is one important aspect of social communication that is grounded in people’s perceptions of relational dynamics and significantly shapes social interactions. We investigate how politeness strategies in AI-generated suggestions affect people’s email writing and alter their perception of the social situation. Through a within-subject online study (N = 52), we found that human writers tend to mirror the type of politeness strategies used in the AI suggestions when writing their own messages. Non-native English speakers are more affected by AI compared to native speakers, and this greater susceptibility to AI influence is partly mediated by higher reliance on AI tools. In addition, writers’ social perception is also influenced by AI. When writers are exposed to more deferential politeness strategy suggestions, they tend to perceive the social relationship as more distant. These findings highlight the need for better design of AI writing assistants that account for social contexts and individual differences.