Why there are so many star ratings
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Illustration: Aïda Amer/Axios
There's a good reason why customer ratings on sites like Amazon or Tripadvisor are presented with a visual star rating: Those ratings are perceived as being higher than those presented numerically.
Why it matters: Consumers evaluate ratings differently depending on the format in which the ratings are presented, per a new paper published in the Journal of Marketing Research.
The big picture: When we see pictures of stars, we count how many lit-up stars there are, including any partially lit stars. When we see a number, we focus on the initial digit.
- The result is that we tend to round up star ratings and round down numerical ratings.
How it works: Let's say someone uses a moon-based rating system, and gives an object 2.5 moons out of 5. When asked, some 70% of respondents will say that's "around two moons" since most people round down rather than up.
- On the other hand, if the same object gets a rating of 🌕🌕🌗🌑🌑, 80% of respondents will say that's "around three moons" since most people round up rather than down.
What they're saying: "Our results suggest that the brain representations that are activated when you process stars are completely different from the brain representations that are activated when you process Arabic numerals," co-author Manoj Thomas, of Cornell University, said in announcing the results.
🍷 For example: The 100-point wine-rating scale, as popularized by Robert Parker, in practice is a 20-point scale where most wines get a first digit of 9 and the rest get a first digit of 8.
- While the fact that it's numerical means consumers tend to round down, that's compensated for by the fact that even after rounding the numbers are high.
The bottom line: Dark patterns are everywhere.
