4 ms·
This is a great discussion of the mechanics of rendering star ratings in a browser. I'd love to see a companion theory post on how to intelligently compute and
by mhartl 15y ago
This is a great discussion of the mechanics of rendering star ratings in a browser. I'd love to see a companion theory post on how to intelligently compute and rank such ratings. The arithmetic mean is notoriously sensitive to outliers, and the consequences are sometimes severe: I know a resort in Thailand that used to be ranked #1 on TripAdvisor on its island (Koh Phangan), only to fall to #17 after a 1-star review. (The tragedy is that, if you read the review, it's clearly positive—the reviewer evidently thought that 1-star was best. D'oh!) In addition, any sensible ranking should take into account statistical significance, so that (say) a 4.6 ranking consisting of 45 reviews (possibly) gets ranked above a 5-star ranking consisting of one review. How does Airbnb handle these cases, or does it just punt by calculating and sorting the arithmetic mean?
- gwillen 15y agoUse the algorithm given here: http://www.evanmiller.org/how-not-to-sort-by-average-rating.html http://www.evanmiller.org/how-not-to-sort-by-average-rating....
- starwed 15y agoSeems like a site with lots of heavily rated products could do a bit better -- you might be able to use your database of known distributions to inform your prior.
- samstokes 15y agoAlso the response article at http://masanjin.net/blog/how-to-rank-products-based-on-user-input.html http://masanjin.net/blog/how-to-rank-products-based-on-user-... is interesting.
- BerislavLopac 15y agoThank you guys, I'm just working on an app that requires calculating scores on user input, and these articles are pure gold! :)
- deleted 15y ago[deleted]
- nkurz 15y agoThere's some good discussion of one approach here: http://news.ycombinator.com/item?id=3046785 http://news.ycombinator.com/item?id=3046785
- nazar 15y agoI am super surprised by your comment, because thats exactly the question I asked my friend yesterday. I am trying to implement a ranking system on my website, so I asked my more experienced friend about it and he recommended me one book: Programming Collective Intelligence Building Smart Web 2.0 Applications by Toby Segaran, O'Reilly http://shop.oreilly.com/product/9780596529321.do http://shop.oreilly.com/product/9780596529321.do
- Robin_Message 15y agoI just got that off my shelf, and page 25 says to use the arithmetic mean. I can't see anywhere where it talks about outliers or better averages.
- ajtaylor 15y agoThanks to the above comments for all the links! I'm about to start on a new project at $work, for which I think those postings will be very useful.