Abstract
As virtual influencers (VIs) increasingly adopt interactive features, their effects on advertising remain underexplored. This dissertation examines how interactivity between consumers and VIs shapes advertising responses. Drawing on the Persuasion Knowledge Model, it further investigates how interactive experiences influence perceptions of VIs, evaluations of persuasion, and advertising outcomes. The dissertation comprises three studies. Study 1 reviews 143 articles and identifies fragmented definitions of interactivity. It reconceptualizes interactivity as two orthogonal components, control and response, whose combination produces four typologies: no interaction, passive viewing, unreciprocated control, and reciprocal interaction. Study 2 uses 15 in-depth interviews and grounded theory to explore how interactivity is understood in VI advertising and how it shapes outcomes. The findings clarify consumers’ understanding of control and meaningful response, identify evaluative persuasion knowledge as more influential than conceptual persuasion knowledge, and highlight AI literacy, warmth, and competence as key mechanisms. Study 3 uses a 2 (control: absent vs. present) × 2 (response: absent vs. present) experiment to test mediation effects and compare the four interaction typologies. Results show that control and response improve advertising and brand attitudes, while warmth, competence, and perceived manipulation intent mediate these effects. This dissertation advances communication theory by reconceptualizing interactivity and explaining how interaction typologies shape VI advertising responses. It extends the Persuasion Knowledge Model by emphasizing evaluative persuasion knowledge and AI literacy and offers practical guidance for designing effective VI interactions.