For most the argument over whether Matt Garza or James Shields is a better pitcher is probably a tired debate at this point. Lines have been drawn and the spirit of the opposition only serves to push sides to a more extreme position. I'm going to to try to refrain from  taking any sides here because frankly I still don't believe its clear cut. Three years of starts is a lot of useful data. Anyhow on to the three-year  findings.

Matt Garza has the edge in game score, both the average and the median. Shields has a decisive FIP advantage, while the fact that Garza owns the median may give an indication that he is more prone to blowing up. Runs against average favors Garza. Runs against is generally not a preferred metric, but over large sample sizes it can prove quite valuable. A half run over a three year period in front of the same defense is something to consider.

These figures tell us overall how the pitchers have fared, but what if we look at each metric on a game-by-game basis sorted from the best to the worst for each pitcher? Surely, consistency is something to consider. First FIP by start:

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Shields pretty much owns Garza from start to finish when it comes to FIP except for a convenient blip around the median. The difference grows much greater towards the lower end of the spectrum. For the sake of a decent chart, anything above 10.00 was listed as 10.00. How about GameScore? For those unfamiliar baseballreference.com has you covered:

GmSc - Game Score - This is a value created by Bill James that evaluates how good a pitcher's start was.

Start with 50 points. Add 1 point for each out recorded, (or 3 points per inning). Add 2 points for each inning completed after the 4th. Add 1 point for each strikeout. Subtract 2 points for each hit allowed. Subtract 4 points for each earned run allowed. Subtract 2 points for each unearned run allowed. Subtract 1 point for each walk.

 

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The gamescore chart shows Shields to be more consistent, but with Garza outperforming Shields up to about the midpoint, with Shields outperforming Garza over the weaker half of the starts. Finally RA/9:

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I like this chart as you see the extended bars for both shutouts and implosions for Garza. Its pretty clear Garza has had the higher highs and lower lows than Shields. Which pitcher is better? I'll leave that up to the community to debate.