Hey Cub fans--
I was reading Brett's post on "hey Barney is doing good" today and it got me thinking about BABIP and how that stat comes into play in almost any discussion of any hitter. How accurate is it? What variables come into play? What factors are under a player's control? So I went 2/3ds of the way down this path (which I will share) and I hope someone can help me out with the last part.
First, http://www.fangraphs.../offense/babip/ explains the basic nature of BABIP, and that there are 3 main variables that can affect rates: defense, luck, and changes in talent level. The average rate is around .290 to .310, and when players deviate from this they are likely going to regress back to average. Finally, it is more accurate to look at career rates than the average rate, because hitters do have some control (i.e. Ichiro and his career .357 rate).
But it got more interesting. In a super-cool article by Chris Dutton at http://www.hardballt...ters-and-babip/, he talks about predicting BABIP by adding .120 to the line drive percentage (the *old* xBABIP). He went on to create a new model (*new* xBABIP) that takes a lot more factors into consideration: speed, contact rate, hitters eye, flyball/groundball ratio, pitches per appearance, park, etc. He then (using date from 2002-2008) takes the "luckiest" and "unluckiest" hitters to test his model against, which works much better than the old xBABIP. He also predicts certain hitters who will regress in 2009 (this was written in 2008), and has this gem: "maybe Geovany Soto isn't quite this good." Ha. This article is definitely worth a read.
Anyway, there's a calculator out there where you can plug in player data and see what their xBABIP will be based on this new model. It's available http://www.hardballt...bip-calculator/ here, and also in some openoffice spreadsheet that I couldn't get to work. The problem is that I can't find any way to get a hitter's number of flyballs, popups, and ground balls.
Does anyone know where to find these? Anyone feel like plugging them in for Barney (and some other Cubs) to make some predictions for the rest of this season? Because I'm with Brett--I've always felt Barney has more offense in him than meets the eye, and I'd like to add some statistical evidence to that belief. Plus it's just kind of cool.
As a final takeaway, and given the predictive success of the xBABIP model, it is important to remember that there are many different factors that can help explain significant variations in BABIP. Is a hitter improving his eye at the plate? Taking more pitches? Hitting more line drives? Making solid contact? It's easy to oversimplify statistics sometimes, and I think that happens quite a bit with BABIP.
Hopefully someone out there can help me out with taking this to the next step. Otherwise, just some interesting baseball stuff to know and think about!