Are We What We Buy?

A new study examines the role self-expression plays in online buying decisions.

June 13, 2017

| by Martin J. Smith


People ride escalators inside a shopping mall. | Reuters/Rodrigo Garrido

We buy things not only to show who we are, but also who we are not. | Reuters/Rodrigo Garrido

Online ratings are ubiquitous these days and you might assume that the higher the average rating, the more likely you are to buy a particular product.

Not always, say two Stanford Graduate School of Business professors who tested the influence of online product rating on consumer behavior.

S. Christian Wheeler and Baba Shiv, both marketing professors, sought to find out how people view products that generate vastly divergent opinions among other consumers. Their research, conducted with Bella Rozenkrants, who earned her PhD from Stanford GSB in 2015, showed that the impact of ratings depends on what you are buying and why.

“We might think that products with higher average ratings would be preferred,” says Wheeler. “But a lot of sites like Amazon don’t just provide overall average ratings, they provide a distribution of ratings” showing the percentage of people who rated the product from a high of five stars to a low of one. “We wanted to look at what inferences, if any, people draw from those distributions.”

That’s where things got interesting. While self-expression may not matter if you’re buying light bulbs or other utilitarian products, experts have long known that people often buy things as a way to say something about themselves, whether that’s a Miley Cyrus T-shirt or a car.

The new study found that the more polarizing the product, the more likely consumers are to see it as a way to express their taste and personality, and people who are a little unsure of themselves find such products to be more desirable.

“Products that are more polarizing — those with more five-star and one-star reviews than the ones with a single peak in the middle — are preferred by people who have self-expression needs,” Wheeler says.

For example, you may buy a car just to get around town. “A Honda Civic is great for that,” Wheeler says. “It’s cheap. It’s reliable. It’s very utilitarian.”

But a Honda Civic doesn’t say much about the driver the way a Prius or Hummer might. “You don’t need a Hummer to get groceries,” Wheeler says. “You buy a Hummer to say something about who you are. Its polarizing nature makes it a great vehicle for self-expression.”

Adds Shiv: “Think about the last time you were at a wine-tasting event. People were buying wine based on their preferences, but some people choose a wine because the label is unique. That’s clearly meeting a self-expressive need.”

Shiv says he was struck by the counterintuitive nature of the study’s results: “Intuition suggests that people just go for high ratings, but we found people with self-expression needs preferred polarizing products, even though they had a greater number of negative ratings.”


You buy a Hummer to say something about who you are. Its polarizing nature makes it a great vehicle for self-expression.
S. Christian Wheeler

The conclusions can apply to one’s tastes in areas such as food, art, and literature. “If you think about polarizing things in daily life — say, stinky cheese, or avant-garde classical music, or B movies — you probably feel like you learn more about a person who likes those things than if they say they like cheddar cheese, pop music, and blockbuster films,” Wheeler says.

“Although adopting polarizing products is not without risk — by definition, a large number of people dislike polarizing products — this risk is outweighed by the benefits of clear and defined self-views,” the study says. “In our quest to say who we are, it helps to simultaneously say who we are not.”

These findings can inform a retailer that caters to adolescents whose self-identity is uncertain, Shiv says. Since style choices are an important way teenagers express themselves, an online retailer catering to that demographic might benefit by building ratings distributions into its online experience, rather than just showing an average rating.

One casualty of this new way of doing business: the declining influence of sales people in brick-and-mortar stores. “There used to be a person who’d say, ‘Hey, that looks great on you,’” Shiv says. The online equivalent is perhaps the comments section on a shopping website.

“So maybe that’s the next step for us to examine,” Shiv says. “Maybe people are seeing what others are saying and deciding if they agree or disagree with that person.”

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