Rubrics And The Bimodality Of 1-5 Ratings

http://zedshaw.com/blog/2009-11-6.html

by slig • 17 years ago

22 5 17 years ago

urlwolf• 17 years ago

Anyone knows a reference for this bimodality Of 1-5 Ratings? This is not what I see in amazon. Votes are not normally distributed, sure, but they tend to cluster on the upper end of the scale. The mean for amazon votes (note that since the distribution is not normal, the mean is meaningless) is something like 3.4.

mattyb• 17 years ago

Quite possibly a terrible example (+ hasty generalization, etc.), but here goes:

http://www.amazon.com/Structure-Interpretation-Computer-Prog...

adi92• 17 years ago

I think a closed forum with users who have established definitions for the difference between what each number of the scale implies would have a bimodal distribution. Sites like youtube ( http://youtube-global.blogspot.com/2009/09/five-stars-domina... ) and amazon ( http://portal.acm.org/citation.cfm?id=1562764.1562800&co... ) have more of a J-curve

CoryOndrejka• 17 years ago

I can't find solid analysis of Amazon's rating system, but neither YouTube nor Netflix are bimodal:

* YouTube is all 5 stars (http://youtube-global.blogspot.com/2009/09/five-stars-domina...)

* Netflix: 3, 4, and 5 dominate (http://www.timelydevelopment.com/demos/NetflixPrize.aspx)

wsprague• 17 years ago

I liked the way he applies moderately useful statistics to a real world application, mostly just as an example of how we all could be using the standard deviation along with the mean.

Rubrics And The Bimodality Of 1-5 Ratings

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