Date of Award


Degree Type


Degree Name

Master of Philosophy (MPHIL)


Computing and Decision Sciences

First Advisor

Prof. CUI Geng

Second Advisor

Prof. LIU Liming


Online product reviews have become an important and influential source of information for consumers. Firms often manipulate online product reviews to influence consumer perceptions about the product, making it a research topic of urgent need for theory development and empirical investigation. In this thesis, we examine how consumers perceive and respond to the three commonly used manipulation tactics. Firstly, an exploratory pre-study via in-depth interviews with online shoppers indicates that consumers commonly have the knowledge for online review manipulations as well as for detecting them. In the first study, a survey was used to investigate the three popular manipulation tactics in terms of ethicality and deceptiveness. They rated hiding/deleting unfavorable messages as the most deceptive and unethical, followed by anonymously adding positive messages, and then offering incentives for posting favorable messages. In study 2, in a simulated field experiment, we introduce persuasion knowledge to further examine the negative influence of review manipulations on consumers’ attitudes. The results suggest that review manipulation increases suspicion of manipulations but can hardly reduce purchase intention of focal products. We also find that consumers’ persuasion knowledge enhances suspicion of manipulation, but lessens the negative impact of suspicion on purchase intention. The third study uses secondary data of a branded e-retailer and its third party website to cross-validate the effect of manipulations on product sales. The results confirm our hypotheses that review manipulation are effective in promoting sales; however, this influence would decrease over time.

This research contributes to the online marketing literature by augmenting the Information Manipulation Theory and Persuasion Knowledge Model to examine the deceptive persuasion in the online context and its impact on consumer behavior. Furthermore, we also contribute to the literature of online WOM by empirically examining the influence of review manipulations on sales. Our findings provide valuable insights to practitioners and policy makers on the pitfalls of online manipulation activities and the need to ensure the healthy development of e-commerce.


Online Review Manipulation; Persuasion Knowledge Model; Information Manipulation Theory

Recommended Citation

Zhuang, M. (2014). Buyer beware: Consumer response to manipulations of online product reviews (Master's thesis, Lingnan University, Hong Kong). Retrieved from