Class comparing change in EMP under AIC from merging 2 nodes. More...
Class comparing change in EMP under AIC from merging 2 nodes.
Under AIC, EMP is -1 x sum over leaves of (counts in leaf x (ln(count in leaf /(n x vol of leaf))) where n is the total number of data points in the histogram
For two subleaf nodes we are comparing the change in -1 x the sum over leaves of (counts in leaf x (ln(count in leaf /(n x vol of leaf) which would result if each node were to be the one to be merged.
Merges take from the left of the queue first ("smallest")
The smaller (more negative) the value returned by getMergeChangeEMPAIC(), the more a node will reduce or least increase the overall EMP by being merged, so it should be lower, ie more to left, in the ordering.