The idea is to help stylistic comparisons. Suppose you're studying several versions of a story, or different translations of it. If one version uses kill and another has assassinate, you can use this function.
The procedure compares all the words in both lists and will report on all those which appear significantly more often in one than the other, including those which appear more than a minimum number of times in one even if they do not appear at all in the other.
How to do it
1. In the menu, choose File | Compare 2 wordlists.
2. Word list 1 will be treated as your study word list. It will be compared with list 2 as if it were a reference corpus.
You will see the results in one of the tabs at the bottom of the screen.