TEARS.... can't stop laughing at that. What a terrible stat. I dunno. It seems pretty sound. Since you subtract the team winning percentage with him playing from the winning percentage with him not playing, you avoid differences caused by differences in overall team quality and ballpark factors. It could be flawed for certain positions like catcher, since some tend to play when only certain pitchers are on the mound. The question is whether the stat is consistent over time. If a player has consistently the same or a similar Neifi index season after season over the course of his career, and/or if the Neifi index of players with similar numbers is similar over the whole of MLB, we can't simply dismiss the stat as gibberish. :lol: