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Topic: Is there a way to calculate an average ranking from uneven lists?
Replies: 15   Last Post: Oct 30, 2013 12:18 PM

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Jennifer Murphy

Posts: 24
Registered: 2/23/12
Re: Is there a way to calculate an average ranking from uneven lists?
Posted: Oct 28, 2013 8:09 AM
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On Mon, 28 Oct 2013 00:31:31 -0700 (PDT), grahamcooper7@gmail.com wrote:

>On Monday, October 28, 2013 12:14:36 AM UTC-7, graham...@gmail.com wrote:
>>
>> SITE 2
>>
>> BOOK 1 100%
>>
>> BOOK 5 80%
>>
>> BOOK 3 60%
>>
>> BOOK 11 40%
>>
>> BOOK 2 20%
>>
>> BOOK 4 0%
>>
>>
>>
>>
>>
>>
>>
>> Then to modify each books rank use:
>>
>>
>>
>>
>>
>> BOOKRANK = (BOOKRANK) + %*TOP - (100-%)*BOTTOM
>>
>> / 2
>>
>>
>>
>>
>>
>> If you use annealing temperatures its like this:
>>
>>
>>
>>
>>
>> BOOKRANK = (BOOKRANK) + TEMP*%*TOP - TEMP*(100-%)*BOTTOM
>>
>> / (TEMP+1)
>>
>>

>
>
>Not quite right, with the bottom rank for each site being around 0.5
>and the top ranks 2.0, they are meant to be multiplied not added.
>
>
>SITE TOP BOTTOM
>1 1.0 -1.2
>2 1.1 -0.8
>3 0.8 -0.9
>
>
>That might work better with my formula!
>
>
>
> BOOKRANK = BOOKRANK + TEMP*%*TOP + TEMP*(100-%)*BOTTOM
> / (TEMP+1)
>
>
>
>
>But you'll get a good result with a simple SCALAR for each site too.
>
>BOOKRANK = ( BOOKRANK + TEMP*WEIGHT*% ) / (TEMP + 1)
>
>that's what I used on horse races!
>
>
>
>That gives each RACE a CLASS which helps pick trifectas!
>With books there could be a big variation in GENERAL REVIEWS (wide variance)
>and specific review sites of books all in much the same score anyway...
>which is where the TOP and BOTTOM more complicate spread calcs. would
>improve the result..
>
>
>Herc


That's a lot to digest. It'll take be some time to think about it.

Thanks for posting.

If you have time, maybe you can apply your method to the sample data I
posted for Virgil:

Let's consider some actual data. Here are 3 sample lists each containing
5 books, but not the same 5 books:

Rank List 1 List 2 List 3
1 A B F
2 B A H
3 C E C
4 D G D
5 E D A

When listed by book, the data looks like this:

List 1 List 2 List 3
Books Rank Rank Rank
Book A 1 2 5
Book B 2 1
Book C 3 3
Book D 4 5 4
Book E 5 3
Book F 1
Book G 4
Book H 2

How would you calculate average rankings?



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