Concave or convex? The impact of display surface curvature on social appeals’ persuasion: the mediating role of self–other overlap

Purpose Marketing persuasive materials are often displayed on a curved surface (e.g. a curved hallway). This study aims to investigate how the curvature (concave vs convex) of a display surface influences the persuasion of the marketing appeals presented on it. Design/methodology/approach The conceptual framework was tested in a field experiment, a lab experiment and two online experiments on Amazon Mechanical Turk. Analyses of variance and mediation analysis were used to test the hypotheses. Findings This research demonstrates that a concave (vs convex) display surface may increase persuasion for marketing materials with social appeals. This occurs because a concave surface enhances consumers’ perception of self–other overlap, which is matched with the content of the social appeal presented on it, thereby enhancing the appeal’s persuasiveness. It further identifies the appeal content as an important moderator of the effect; a convex (vs concave) display would enhance persuasion when the marketing materials contain personal appeals. Research limitations/implications Future research could investigate how a time delay (e.g. hours, days) and the curvature of a display board or wall would play a role in the effect of display curvature. Practical implications The findings offer a novel, simple and cost-effective approach to enhance persuasion for both nonprofit and for-profit marketing materials. Originality/value This research contributes to the persuasion literature by investigating the impact of one ubiquitous but overlooked aspect of the message setting (i.e. the curvature of the message’s display surface) on persuasion while holding the message source and content constant. It also advances knowledge on consumer shape perception by examining an underexplored shape (i.e. the curved shape of a display surface) that is nondiagnostic in message persuasion.