An extended model of review helpfulness : Exploring the role of tie strength, perceived similarity, and normative susceptibility

Previous studies on review information evaluation focus on the important roles of two key factors namely argument strength and source credibility but pay less attention to how social influence and social relationship exert impact on this information evaluation behavior. To fill this research gap, based on the similarity-attraction theory and social capital theory, we articulate how source credibility is determined by two social relationship factors: tie strength and perceived similarity. Further, drawing upon the social influence model, we propose that the susceptibility to normative influence intensifies the impact exerted on source credibility by tie strength and perceived similarity. Also, relationships between argument strength and review helpfulness and between source credibility and review helpfulness are both moderated by normative susceptibility. A survey is conducted to test the proposed research model and the results suggest that hypotheses are supported. The results offer important and interesting insights to information systems research and practice.