Ratings and Reviews and the Psychology of Popularity

A version of this article was originally published by Total Retail on October 5, 2017.

The Association for Psychological Science recently published an interesting study on consumer shopping behavior, showing that when two comparable products have similar average ratings, shoppers are significantly more likely to choose the product with the larger number of ratings.

This finding won’t surprise e-commerce retailers, but in the psychology world, it’s an illustration of herd mentality leading to irrational decisions. When two comparable items have low ratings, it would be more logical for shoppers to pick the one with FEWER total reviews, as it’s possible that the poor average rating is a fluke — an unrepresentative sample of grumpy reviewers. An item which has a large number of low ratings, on the other hand, is very likely to actually be a dud. Yet even in these cases, where both choices are poorly rated, shoppers prefer the one with the larger number of reviews, because a high review count signals popularity, and people tend to buy what’s perceived as popular.

The e-commerce implications of this study are clear — retailers need to signal to shoppers that the items they sell are popular. Travel sites do this well by showing an indication of the recency and volume of bookings. Take Hotels.com for example:

And here’s another example from Orbitz:

On retail sites, product review volume is among the most powerful ways to signal popularity. While influencing review volume may feel difficult because it seems there are only so many people that want to write product reviews, there are actually many strategies to increase review collection.

For starters, it’s a mistake to think that the number of product reviews that can be collected has a hard limit based on the willingness of customers to write them. It’s more like drilling for oil — some comes out in a gusher, but there’s a lot more in the ground that you can get out by using clever techniques. To illustrate, we recently had a customer begin sending follow-up “please review your purchase” emails a few days after their first request. The retailer expected that the follow-up would get a much lower response rate than the initial email, believing that most customers motivated to write a review would respond to the first request. Surprisingly, the response rate to the follow-up email was 80 percent of that of the initial email — nearly the same. This showed that many of those customers that didn’t respond to the first email had no aversion to writing a review, they just happened to get the request at the wrong moment.

Since many customers ignore a request to write a review for reasons of convenience rather than intent, retailers can increase review collection simply by taking the friction out of the collection process. Strategies aimed at motivating review writing (e.g., incentives) can help, too, but they can also have side effects (e.g., reduced trust). Reducing friction is the low-hanging fruit. Technology that enables customers to write and submit reviews from inside an email rather than requiring a clickthrough to a web form can more than double submission rates. A simple change from a button that says “Click to write a review” to a display of five stars with the message, “Start by rating it” can add 50 percent to the response rate. Allowing users to write reviews before requiring authentication, rather than leading with a log-in demand, can double collection rates.

On mobile devices, allowing photos to be submitted without first requiring the user to author a review can multiply visual content collection up to four times. Asking a user who has just submitted a review to review other items they’ve purchased is five times more likely to produce an additional review than the initial email. It’s common for this “Do More” technique to increase total review volume by 50 percent to 100 percent.

The lessons are clear: Increasing review volume can have a major impact on sales by tapping into the popularity effect, and review volume can reliably be increased with the proper tools and techniques.