Date of Award

Spring 2018

Document Type


Degree Name

Doctor of Philosophy (PhD)




Business Administration-Marketing

Committee Director

Yuping Liu-Thompkins

Committee Member

Mahesh Gopinath

Committee Member

Wu He


Online reviews are gaining importance in determining consumers’ purchase decisions since many consumers trust them as much as personal word-of-mouth. One aspect of reviews that has received great research attention is valence. Valence refers to consumers’ positive or negative evaluations of products. It can be reflected by star ratings or dichotomous choices such as recommendation rates and thumbs up or down rates. The effects of valence reported in previous studies have been equivocal at best. Therefore, the purpose of this dissertation is to identify factors that help reconcile these inconclusive findings.

The first essay examined emotional arousal (e.g., sad versus angry) as a moderator of the relationship between valence and consumer decisions. Through two lab experiments and one field study utilizing the browsing and purchasing data from a major online retailer, I find that the effect of emotional arousal can be different along the consumer purchase journey. During the search stage, consumers use emotional arousal as a heuristic to make their choices. Extreme reviews (e.g., five-star or one-star rating) with high emotional arousal indicate reviewers’ bias and lack of self- control and are deemed less informative about product performance. Therefore, emotional arousal weakens the effect of valence on consumers’ consideration choices. However, when consumers are at the purchase stage, a more complex cognitive process emerges. Even though they believe that extremely negative reviews with high emotional arousal are uninformative, their anticipated regret leads them to reject products associated with those reviews.

The second essay suggests that how consumers process valence and volume (i.e., the total number of a product’s reviews) depends on the framing of the numeric information, which subsequently determines the importance of valence in relation to that of volume in consumers’ purchase decisions. Specifically, consumers will utilize different approaches to processing valence and volume information when valence is framed as a percentage of volume (60% of 500 customers recommend) versus when it is represented as an absolute number (e.g., 300 out of 500 customers recommend). Through five lab experiments (including an eye-tracking study), I find that due to the fundamental differences between these approaches, consumers are likely to tradeoff valence for high volume if the valence information is expressed as percentages. However, the dominant effect of review volume diminishes if the absolute number format is applied. The effect of numerical framing thus helps newly introduced high-quality products overcome their disadvantage due to low review volume.





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