Self Motivated vs. Prompted Reviews

How Does Self Selection Impact Star Ratings for Online Reviews?


Using data supplied by PowerReviews, a company that works with global brands & retailers to collect and display customer ratings and reviews, the Medill Spiegel Research Center analyzed how ratings in customer reviews varied depending on if a customer was a verified buyer or an anonymous consumer.


In the previous study on ratings in partnership with PowerReviews, Medill Spiegel Research Center examined the circumstances under which reviews are most impactful on purchase behavior. In this study, we set out to examine how reviews differ depending on where they originate from and how this impacts sales. We looked at two groups: verified buyers and anonymous consumers. Verified buyers are consumers who make a purchase online and are emailed after purchase asking them to review their purchase. Anonymous consumers are those whose purchase cannot be confirmed through an online sales transaction linked to a review prompt (i.e. purchased in store or received the item as a gift). In this study we examined at two key questions. First, how do reviews from these two consumer groups vary? And, which type of review is more influential to future shoppers and more impactful on sales.

Spiegel Insight Proof Action Items for Marketers

Reviews from verified buyers have average higher ratings.

The average star rating for reviews from verified buyers is 4.34 compared to 3.89 for reviews written by anonymous consumers. In addition, reviews from verified buyers contain a high percentage of 5 star ratings, while reviews from anonymous customers have a larger percentage of 1 star ratings. (This is consistent with the theory that people who are self-motivated to write a review have more extreme, and often more negative reviews).
Implement a post-purchase email plan to collect reviews from verified buyers. If you allow reviews from anonymous customers, display a badge indicating "verified buyer" so you can be transparent in giving shoppers the information they need in accessing the credibility of the review.

Verified buyers select more positive tags.

PowerReviews allows users to add tags to their reviews by adding the tags "Pros" (i.e. "comfortable"), "Cons" (i.e. "doesn’t wash well"), and "Best Uses" (i.e. "great for date night"). Verified buyers had 6.5 percent more "Pros" tags and 50 percent less "Cons" tags.
Consider adding the ability for consumers to tag their reviews with labels making it easier for consumers to be specific with feedback and shoppers to more easily obtain information about the product.

Average rating for reviews from verified buyers remains steady over time.

Our research team found that ratings from verified buyers have higher star ratings and are more consistent over time. In contrast, the average star rating from anonymous consumers declines over time. Verified buyers are asked to fill out a review via email and are taken to a page where they don't see any other reviews and aren't influenced by the reviews of others. If an anonymous consumer goes to write a review, he or she can see the average star rating. Since reviews from anonymous buyers are often lower in general, if they had a bad experience with a product, they are more likely to give an even lower rating that they would initially to bring the overall rating down.

Think about sharing verified reviews only as the default setting on your review platform. Showing only verified reviews "nudges" the consumer toward the more credible reviews but doesn't censor the views from anonymous consumers, as customers can read whatever review they'd like

Reviews from verified buyers impact purchase.

Our research team found that customers don't place more weight on reviews from verified buyers vs. anonymous consumers when making purchase decisions. However, more positive reviews are correlated with greater likelihood of purchase, and reviews from verified buyers are more positive overall (4.34 stars compared to 3.89 stars for anonymous consumers). Additionally, PowerReviews has evidence from internal data that 70 percent of reviews are collected from emails sent post-purchase.

Consider incentivizing reviewers to write reviews to obtain more reviews from verified buyers. But, be transparent on your site that the incentive (i.e. entry into a sweepstakes) was used to solicit the review. Alternatively, consider non-prize incentives.  Amazon and Yelp both give "stars" or "badges" to those who post frequent reviews, designating them as opinion leaders.

Academic Publications

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