Rubrics And The Bimodality Of 1-5 Ratings(zedshaw.com)

22 pointsby slig17 anni fa5 comments

Rubrics And The Bimodality Of 1-5 Ratings

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

5 comments

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.

CoryOndrejka17 anni fa

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)

adi9217 anni fa

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

mattyb17 anni fa

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

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

wsprague17 anni fa

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.