Quantifying the Twins Spring Training bullpen battle: Bullpen Battle Dashboard

Here is the basic premise: The Twins have a whole bunch of relievers in their Spring Training Camp who are batting for 3 spots on the 25-man roster. I listed and analysed these players previously. Spring training is long and it is hard to track each appearance of each player, trying to have an objective view of how this battle might be ending (or at least trending,) especially, when the usual statistics fail with such a small sample size. Yesterday I created a dashboard to look at each pitcher's performance on a daily basis and use visual color clues to get the big picture at once. That was step one. But for some reason I was not really happy with it.

My major objection to that first iteration was that individual daily performances were subjective. "Average", "above average" and "below average" were determined by glances at boxscores and what I saw or heard in games. Not too good. Plus, there are various degrees of greatness or non-greatness, and those need to be separated. Thus the need for quantification and for an objective way to measure each pitcher's daily performance and I think that I found it: It is a measurement created by Bill James more than a decade ago called "Game Score". Truth of the matter is that James created that to measure starting pitcher performance, but I think that it is applicable here and will fit my purpose (albeit things will be a bit compressed on the top, but the middle and the bottom will differentiate nicely.) What is Game Score? Here is how it is determined: You start with 50 points for each pitcher. Add 1 point for each out. Add 1 point for each strikeout. Subtract 2 points for each hit. Subtract 4 points for each earned run. Subtract 2 points for each unearned run. Subtract 1 point for each walk. There is a point bonus for pitching more than 4 innings as well, adding 2 points for each IP after the 4th, but this is not too applicable here. All you need to calculate Game Score is a box score and a calculator. Done deal. However, there are no box scores for B games, and the caveat is I cannot include them (which might not be that bad in the big schema of things.)

I am ready to present the final version of the 2012 Spring Training Bullpen Battle Dashboard. I will update the dashboard and post it on a weekly basis. The next update will be early next week before the first cuts are made. Like the previous version, performances are classified as "above average" (green color), "average (yellow), "below average" (red). But now there are numbers there to tell how much bellow or above average each performance is. I also average all performances to day, list that average in the first column and color the pitcher's name accordingly as well. Following, there is a ranking of all pitchers in the list based on their average game score this spring training. Game Scored of 49-51 are "average", everything higher than 51 "above average", and everything below 49 "below average".

Here is what the dashboard looks, including yesterday's game at Baltimore:

And here is the ranking:

Terry Doyle 56
Carlos Gutierrez 55
Liam Hendriks 55
Matt Maloney 54.5
Jared Burton 53.5
Tyler Robertson 53
Aaron Thompson 53
Brendan Wise 53
Casey Fien 52.5
Kyle Waldrop 52
P.J. Walters 52
Esmerling Vasquez 51.5
Luis Perdomo 49.5
Jeff Manship 49
Alex Burnett 48.5
Daryl Thompson 48
Lester Oliveros 46
Phil Dumatrait 45
Scott Diamond 42
Jeff Gray 41
Jason Bulger 25
Deolis Guerra 21

Samuel Deduno DNP

Of course this is a small sample size at this point and will change during the next weeks, but I think that I have found a way to dashboard Twins' pitchers' performance this Spring. I am keeping track of the performances of the pitchers who I consider locks to make the team, but I will wait to publish for another week or so, because these players are not part of this discussion.

There are some pretty obvious outliers here, especially at the low end of performance, so it will be interesting to see how things will play out this weekend and early next week before the first cuts.

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