July 20, 2020

Is Online Review Bias Real?

Is online review bias real? In 2018, Harvard Business Review (HBR) published a report exploring the true quality of online reviews on websites like Yelp, Tripadvisor, Facebook, Google, and Glassdoor.

According to the report, reviews typically have a distribution of opinion that is “highly polarized, with many extreme positive and/or negative reviews, and few moderate opinions.”

This explains why it isn’t unusual to encounter reviews by customers who loved their experience so much that they gave the business a 5-star rating. It’s also common to see reviews from those so disappointed by (even sometimes angry at) a business that they decided to leave the lowest-rated review possible.


Explaining Review Bias

But what of the oft-silent majority of middle-of-the-road voices? According to HBR, their opinion might not always be accurately represented in reviews. 

“If you had a moderate view, you’re likely to have left no review at all, finding it not worth the time and effort.” 

Unless a person really loved or hated the customer experience, they’re not likely to review a business. This kind of polarization can then lead to others having misleading opinions about businesses.

online review bias

Are Online Reviews Reliable? 

Previous research by MIT also suggested that some reviews could be systematically biased or easily manipulated. 

Among the factors that cause online review bias to happen: social proof, a psychological and social phenomenon where people assume the actions of others in an attempt to reflect correct behavior in a given situation.

The MIT report read, “Our herd instincts — natural human impulses characterized by a lack of individual decision-making — cause us to think and act in the same way as other people around us.”

Social Proof and Biased Reviews

As a powerful form of social proof, reviews can influence what people think they should say. 

A diner’s Yelp review of a Japanese restaurant with 100 reviews and a 4.7-star rating is less likely to go against the grain and offer a counterpoint to the majority’s positive opinion. They’re likely to say the same as other diners did: best sushi ever.

social proof in online reviews

“When we see that other people have appreciated a certain book, enjoyed a hotel or restaurant or liked a particular doctor — and rewarded them with a high online rating — this can cause us to feel the same positive feelings about the book, hotel, restaurant or doctor and to likewise provide a similarly high online rating,” the report added.

There are also situations where extreme views are over-represented, or where social proof pushes consumers to follow their herd instincts. This may negatively affect the quality of data found in online reviews, potentially resulting in information inaccuracies, ratings bubbles, undeserved low scores, and reputation crises.

What Businesses Can Do to Combat Review Bias

In today’s age where reviews have a powerful effect on shopping decisions and consumer behavior, it is critical for companies to introduce mechanisms that improve the quality of their customers’ review data, thereby reducing review bias and the potential for manipulation in online reviews. 

Proactively Ask for Feedback

One way to reduce review bias and balance review sentiment is to facilitate as many authentic positive reviews as possible. This is effective particularly in the early stages of the ratings process. 

There are plenty of options when asking for reviews. You can distribute surveys, implement a customer feedback system, send email and SMS requests, or create review request handouts that are given after completed customer transactions. 

ask customers for feedback

Remind Customers that Their Opinion Helps Others

When asking for feedback, social reinforcement goes a long way. 

“Online reviews are a social endeavor,” the HBR reporters wrote. “People are more likely to leave online reviews when they’re reminded that doing so helps others. Simple pro-social incentives also led the distribution of reviews to be less biased, creating a more normal bell-curve distribution of reviews.”

Provide Motivational Incentives

Incentives do not necessarily mean rewarding reviewers with cash, freebies, or discounts. Non-monetary economic incentives based on the concept of “give to get” can push less vocal middle-of-the-road customers to share their opinions online.

One of the classic examples of this kind of “give to get” mechanism is the Airbnb reviews policy of not making guest reviews public until the host leaves theirs — or the other way around.

In a study, employer review site Glassdoor asked its users to submit content in exchange for free access to valuable information on its website. 

The policy helped Glassdoor draw reviews from a much broader base of users. It also led to a more balanced and representative picture of the distribution of online opinions about given products, services and companies.

Final Thoughts

Customer reviews research shows that 94% of consumers use reviews to guide most of their ordinary purchase decisions. However, reviews are more than a powerful information resource; they also represent a fundamentally social endeavor. By encouraging less vocal customers to join the conversation, businesses can help reduce online review bias, normalize the curve, and improve the quality of data found in reviews.

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