Reconciling the effects of positive and negative electronic word of mouth: roles of confirmation bias and involvement

Purpose The study explored users' tendency of confirmation bias when processing congenial vs. uncongenial electronic-word-of-mouth (e-WOM) about mystery fictions, a hedonic product category with strong experience and hedonic characters. Design/methodology/approach A two-stage judgment approach was employed where the participants were asked to judge a set of mystery novels twice: one before, and another after they were exposed to positive and negative e-WOM. The first-stage judgment established two favored and two disfavored titles by each participant. They were then asked to read six consumer reviews – three positive and three negative – for each of the four titles. The procedures created four review evaluation situations: two congruent and two incongruent, which allowed the authors to assess the participants' perceptions of congenial and uncongenial reviews and their rating adjustments of the titles. Participants' involvement in mystery novels was also measured to test its moderating effect on confirmation bias. Findings Confirmation bias in the evaluation of e-WOM was observed and reinforced by the user's involvement in the genre. Congenial reviews were perceived to be significantly more credible, better reflect the intrinsic value of a title and less subjectively motivated than uncongenial reviews. Furthermore, after exposure to equal amount of positive and negative e-WOM, an asymmetrical adjustment of final rating of the titles was observed. A significantly greater downward adjustment was observed for disfavored than favored titles. Stronger positive confirmation bias was also observed in the evaluation of WOM. Research limitations/implications Previous studies on e-WOM have shown conflicting findings on the relative efficacy of positive vs. negative reviews. By introducing the factor of prior attitudes, the study demonstrated that whether WOM is consistent with an individual's prior attitude, rather than the valences of WOM in itself, determines its persuasiveness. Thus, it established the confirmation bias in users' processing of e-WOM. The finding highlights the importance for marketers to establish a positive initial impression, which, as the findings demonstrated, helps alleviate the damages caused by negative WOM. Originality/value This is the first study that has ever attempted to study the effect of confirmation bias during the users' processing of e-WOM in an experimental setting. By having the participants judge the books before and after exposure to congenial and uncongenial e-WOM, the authors were able to establish the link between the users' prior commitment to a book and their subsequent judgment of both the titles and the e-WOM. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-01-2020-0026