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aiken
Aged Yak Warrior
525 Posts |
 Posted - 2004-06-14 : 20:16:17
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| No, not like "update statistics."I need help with a popularity rating system. It's about what you'd expect: users can vote on an item, and we rank them using avg(vote).However, I'd like to use something less subject to manipulation than a simple average. I know enough about statistics to know what a standard deviation is, but that's about it.Can someone take pity on me and explain how I could easily do something like, for instance, throwing out the top 5% and bottom 5% of votes before taking the average? Preferably something fast and math based rather than iterative and TSQL based, if that makes sense.I'm not married to that particular option; it just seemed like a way to throw out joke or malicious votes. If there's a more pure statistical way to do it, I'd love to hear it.Thanks-b |
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spirit1
Cybernetic Yak Master
11752 Posts |
Posted - 2004-06-16 : 06:40:46
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| something like this:select avg(votes) from table where votes between (min(votes) + 0.05*max(votes)) and (0.95*max(votes))Go with the flow & have fun! Else fight the flow :) |
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dataphile
Yak Posting Veteran
71 Posts |
Posted - 2004-06-17 : 09:19:45
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| Can a person vote more than once for the same item?Firstly prevent this from happening.I guess that every person has to rate the item on a scale (say 1-5)So for every item, calculate the average votes per interval and onlycount the votes that are within one standard deviation from that average.Or simply use the item on the scale with the most votes. "Most people gave this item a 3/5" |
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Statistics help please