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Weighting ratings: Are people adjusting for bias in extreme reviews?
1WMG, University of Warwick.
Abstract:
The increasing importance of consumer ratings raises the question of whether people adjust for potentially fake or biased extreme opinions when judging products. Two studies tested treatments that trimmed the extremes of rating distributions. Neither removing extreme ratings while preserving the mean, nor flagging suspicious extreme ratings, nor priming individuals about review manipulation significantly affect judged product quality on average. However, judgments for specific distributions may be made less extreme by flagging or trimming. On average, it is difficult to override usage of the mean rating as the strongest proxy for product quality. When a weighted-mean model is fitted, the estimated weighting profile is hump-shaped and asymmetric. Consumers appear to discount 5-star ratings but are particularly susceptible to being misled by disingenuous 1-star ratings. The weights suggest that there is a binary bias with an inflection point at 2-stars for product ratings, meaning that any rating above this broadly sends an equally strong positive signal of quality. Further theoretical work is required to understand how people form weights for ratings, and applied work should continue to search for decision aids that could help consumers to better adjust for review bias. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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