As good as computers are at calculating numbers they are really really bad at doing somethings that humans are just great at like making decisions based on fuzzy logic or translating things between languages. In such situations always go for the human at least until C3P0 comes along. Watson cost $3 million to build, good if you want to play trivial pursuit but ask it to choose between competing software vendors and well you will be nowhere.
That’s you numerical based ranking systems for software purchase!!!