Want to save this page for later?

NextGen Magazine


Five-Star Rating Systems Not Very Useful to Consumers

Chris Gaetano
Published Date:
Jul 2, 2019

While the one-to-five star rating system is ubiquitous, a recent article in the Harvard Business Review notes that its inherent problems can mean that the information isn't very useful. For one, the system is not very specific. Additionally, there's a selection bias at work, as those who have the most extremely positive or negative experiences are the most likely to leave a review at all. There's also the matter of grade inflation, where almost no one rates something one star ,and so the real range is between 4.5 and 5, which can mean a difference as small as 0.1 or 0.2 can have far-reaching significance. 

The authors suggested that making the star system more accurate could mean showing average scores for all suppliers in a relevant category, using a sort of "top supplier" designation that is binary in nature, weighting reviews based on variance (e.g., if someone always gives five stars it won't be worth as much), and experimenting with what information suppliers can and can't see. 

A study from last year similarly noted problems with many online rating systems. It found that, due to awareness of how people manipulate scores, consumers are less likely to trust a perfect review. The study, conducted by SmallBusinessPrices.co.uk, found that users find perfect ratings suspicious, with only 10 percent of customers actually taking them seriously. By contrast, 22 percent of people trust three-star ratings, and 35 percent trust four-star ratings.