How to calculate clustering entropy - example and my solution given but is it correct?

Question

I would like to calculate entropy of this example scheme

http://nlp.stanford.edu/IR-book/html/htmledition/evaluation-of-clustering-1.html

Equation of entropy

Then the entropy is (the first line)

So entropy is for this scheme

For the first cluster - ( (5/6)*Log(5/6) + (1/6)*Log(1/6) ) 
For the second cluster  - ( (1/6)*Log(1/6) + (1/6)*Log(1/6) + (4/6)*Log(4/6) )
For the third cluster  - ( (2/5)*Log(2/5) + (3/5)*Log(3/5) )

Final entropy is :

 FirtCluster_Entropy + SecondCluster_Entropy  + ThirdCluster_Entropy

Am i correct?

I'm voting to close this question as off-topic because it does not appear to be a programming question. — High Performance Mark, Mar 03 '16 at 23:50
I vote to move this question to Cross-Validated https://stats.stackexchange.com/ — Snives, Mar 14 '16 at 23:31

score 1 · Answer 1 · edited May 23 '17 at 12:31

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Very close! For the total entropy of the clustering you need need to weight each cluster's entropy by its relative weight. Please see my answer to your previous question https://stackoverflow.com/a/35780505/159646.

Also this should probably be posted to Cross Validated instead of Stack Overflow.

edited May 23 '17 at 12:31

Community

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answered Mar 03 '16 at 20:35

Snives

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@MonsterMMORPG: I also told you you need to weight clusters ... it would be good if you take the answers you get more seriously instead of reasking again and again. – Has QUIT--Anony-Mousse Mar 03 '16 at 22:29

How to calculate clustering entropy - example and my solution given but is it correct?

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