The aim of the present study was to gain a better understanding of the content characteristics that make online consumer reviews a useful source of consumer information. To this end, we content analyzed reviews of experience and search products posted on Amazon.com
(N = 400). The insights derived from this content analysis were linked with the proportion of 'useful' votes that reviews received from fellow consumers. The results show that content characteristics are paramount to understanding the perceived usefulness of reviews. Specifically, argumentation (density and diversity) served as a significant predictor of perceived usefulness, as did review valence although this latter effect was contingent on the type of product (search or experience) being evaluated in reviews. The presence of expertise claims appeared to be weakly related to the perceived usefulness of reviews. The broader theoretical, methodological and practical implications of these findings are discussed.Key words: Online Consumer Reviews, Electronic Word-of-Mouth Communication, Content Characteristics, Content Analysis. doi:10.1111/j. 1083-6101.2011.01551.x With the emergence of consumer-generated media platforms, word-of-mouth conversations have migrated to the World Wide Web (Brown, Broderick, & Lee, 2007), creating a wealth of product information that is often articulated in the form of online consumer reviews (Schindler & Bickart, 2005). These reviews provide product evaluations from the perspective of the customer, and have a strong influence on consumers' product and brand attitudes and purchase behavior (Chevelier & Mayzlin, 2006;D.-H. Park & Kim, 2008;Senecal & Nantel, 2004), even more so than marketer-generated information (Chiou & Cheng, 2003). The persuasive impact of online consumer reviews, as well as of other forms of word-of-mouth, is often attributed to the perceived non-commercial nature of their authors. Consumers are believed to have no vested interest in recommending a product or brand, and their implied independence renders reviews more credible and consequently more useful than marketer-generated information (Bickart & Schindler, 2001;Ha, 2002;Herr, Kardes, & Kim, 1991).As reviews gain in popularity, it becomes harder for consumers to find their way in the wealth of reviews and to assess the usefulness of the information offered (D. -
19the problem of information overload, many review websites have invested in peer-rating systems that enable consumers to vote on whether they found a review useful in their purchase decision-making process. These votes serve as an indicator of review diagnosticity, and are used as a signaling cue to users to filter relevant opinions more efficiently (Ghose & Ipeirotis, 2008;Mudambi & Schuff, 2010).Variations in the proportion of 'useful' votes provide evidence that 'all reviews are not created equal' (Godes & Mayzlin, 2004;D.-H. Park, Lee, & Han, 2007) and, hence, that all reviews are not evaluated as equal. Consumers do not follow a structured format when posting their product evaluat...