Social influence tactics in e-commerce onboarding: The role of social proof and reciprocity in affecting user registrations

Abstract

Given the increasing competition to attract new customers, e-commerce providers (i.e., e-tailers) are being urged to optimize their website onboarding journeys. Design mechanisms employing social influence tactics seem to be promising avenues to effectively improve user onboarding experiences. Specifically, two social influence tactics—namely, reciprocity and social proof—are widely used in practice to reliably enhance user registrations. Yet, researchers have only tentatively examined how these combined tactics affect user onboarding behavior. While combining both tactics may hold synergistic potential, it may also be counterproductive, as too much social influence may backfire. We address this research gap by investigating the distinct and joint effects of reciprocity and social proof on user registration behavior. Drawing on two forms of reciprocity (i.e., utility- and monetary-based reciprocity), we conduct an online experiment (N = 249) and a related randomized field experiment (N = 475,495) to compare both reciprocity variants in combination with social proof and investigate their efficacy for actual user onboarding decisions (i.e., user registrations). Our results show that both social influence tactics and both reciprocity variants have positive effects on users' registration behavior if applied individually. However, when both tactics are employed together, the effect of reciprocity is moderated by social proof such that social proof nullifies the effect of monetary-based reciprocity whereas it amplifies the effect of utility-based reciprocity. Our study thereby contributes to a more advanced understanding of the interactive relationship between reciprocity and social proof and their joint effect on user onboarding decisions.