Calculate the entropy, joint entropy, entropy distance and information content of two splits, treating each split as a division of n leaves into two groups. Further details are available in a vignette, MacKay (2003) and Meilă (2007).

SplitEntropy(split1, split2 = split1)

## Arguments

split1, split2

Logical vectors listing leaves in a consistent order, identifying each leaf as a member of the ingroup (TRUE) or outgroup (FALSE) of the split in question.

## Value

A numeric vector listing, in bits:

• H1 The entropy of split 1;

• H2 The entropy of split 2;

• H12 The joint entropy of both splits;

• I The mutual information of the splits;

• Hd The entropy distance (variation of information) of the splits.

## References

MacKay DJC (2003). Information Theory, Inference, and Learning Algorithms. Cambridge University Press, Cambridge. https://www.inference.org.uk/itprnn/book.pdf.

Meila M (2007). “Comparing clusterings---an information based distance.” Journal of Multivariate Analysis, 98(5), 873--895. doi:10.1016/j.jmva.2006.11.013 .

Other information functions: SplitSharedInformation(), TreeInfo
A <- TRUE