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

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Closed 3 years ago.

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?

回答1:

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.

来源：https://stackoverflow.com/questions/35760706/how-to-calculate-clustering-entropy-example-and-my-solution-given-but-is-it-co