Normalized subset entropy
= Normalized subset entropy
{title2=$h_k^{(n)}=\frac{1}{k\binom nk}\sum_{|S|=k}h(X_S)$}
For a discrete <random vector> with $n$ coordinates, this is the average <information entropy> per coordinate over all subsets of size $k$. Independent coordinates give the same average for every $k$, even when their individual entropies differ. If all coordinates are copies of one random variable $Z$, the average is $h(Z)/k$.