[uruguru]

This post concerns historical sims and the effects of the Pitcher BABIP rating on how the game evaluates of players (or at least presents its evaluation).

I'll try to keep this short... The existence of the Pitcher BABIP rating undermines the rationale of the modern defensive metrics that the game uses to evaluate players. This normally reveals itself in the fielding WAR portion of the position player evaluation, and the entirety of the WAR evaluation for pitchers.

I am not saying this is BAD. The huge benefit of Pitcher BABIP is that the historical sims are more accurate when compared to the historical stat lines for pitchers. For most historical players, I assume this is a huge plus. Please do not construe this post in any way to be lobbying for the removal of Pitcher BABIP. I think a better approach would be to incorporate it more accurately in areas where it seems to be ignored.

However, in historical sims players change teams in ways that they did not in the real world. A mediocre defender will see his defensive performance greatly improve when playing with pitchers with a low BABIP. This is because, unlike the modern game, it is the pitcher who is driving a significant portion of the defensive outcomes, not the fielders.

What does this mean? High-quality defenders will be overrated and low quality defenders will be underrated by the AI. You might see, for example, a second baseman near the top of the various lists in assists, putouts, double plays, etc and then see that the game assigns him a significant defensive WAR. All-Star selections and post-season awards are the significantly impacted -- so I basically assign all of the post-season awards except Silver Slugger (which is purely offensive and unaffected).

Pitcher WAR in the game is based on FIP, which makes perfect sense for the modern game. But because of the Pitcher BABIP rating, pitching is not fielding-independent in the historical game. As a result All-Star selections and post-season awards can be especially wacky in the game. I've just accepted the All-Star selections because it's not worth the effort to deal with.

Anyway, as someone who plays a lot of historical sims, I just wanted to share these observations.