Usage-adjusted starting pitcher stats

AB in DC

OG Football Writing
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Jul 10, 2002
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Springfield, VA
Last night's box score says that Doug Fister pitched 7 2/3 innings, allowing 2 runs (both earned) and 5 hits (1 HR) throwing 108 pitches.

The box score is lie.

What Doug Fister actually did can be best described as two completely separate things:

Thing 1. Fister threw seven scoreless innings, allowing only 3 hits on 98 pitches

At that point, if the Red Sox had scored their usual 1-3 runs over those same seven innings, Doug Fister would have had butt firmly planted on the bench while the bullpen went out and tried to hold the lead. Amazingly, that didn't happen -- the Sox actually scored six runs. Shocking, right? Anyway, that put the team's win expectancy somewhere around 99.5%.

From there, John Farrell had to balance two completely independent goals: (A) Turn that 99.5% win expectancy into a real W, and (B) use the bullpen as little as possible to keep relievers fresh for future games.

That completely changes the calculus of what to do with Doug Fister in the 8th inning. No longer is the team's #1 goal to prevent runs. It's to obtain as many outs as possible until Farrell has to pull him -- basically, the baseball equivalent of running out the clock.

Thing 2: Fister pitched another 2/3 of an inning, giving up 2 more runs, on two hits, throwing another 10 pitches.

Any conventional statistical analysis would treat Thing 2 as a big negative when evaluating Doug Fister's performance. But was it, really? I think not -- win expectancy dropped from 99.5% to about 98.4%, but the bullpen only needed to obtain 4 outs rather than 6. Farrell-bashing aside, I think that's a trade-off that most managers would be comfortable with. So does it really make sense to treat Thing Two pitching stats the same as any other 2/3 of an inning when measuring Fister's performance? Or, alternatively, is this such an unusual situation that it's completely non-predictive of Fister's pitching going forward?

Remember why Defense-Independent Pitching Stats became so important over the past decade or two. The idea is to measure pitching performance separately from what the pitcher has no control over. Just as pitchers have no control over whether the defense successfully turns balls in play into outs, they also have no control over whether the manager leaves him in the game rather than calling on the bullpen. Shouldn't there be advanced metrics that account for this?
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Anyway, the reason I'm posting here is that I haven't really seen any stats or analysis that adjusts for usage patterns this way. I'm interested to hear if anyone has some studies or articles that they can point to.

I can come up with two possible approaches here:
1) Split all starting pitching stats between outcomes that occurred in the first 6 innings (or 5, or 7) vs outcomes that occur in later innings. As the example above illustrates, performance in later innings is highly situational-dependent and doesn't necessarily give an valid measure of the quality of the pitching performance. You could even reclassify those as a kind of "relief" inning and compare those stats to relievers who might otherwise be pitching in those innings -- that has the side benefit of creating a new metric, albeit imperfect, to judge whether managers should leave starters in the game vs call the bullpen.

2) Give starters extra credit for additional outs beyond the 6th (or 7th) inning. That could more faithfully measure the additional contribution by starting pitchers in giving the bullpen a rest, as in the example above, but I can't think of a good way to do it.
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So what say you, SoSH Nation? Am I already late to the party on this, or is this worth thinking about?
 

Brand Name

make hers mark
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Oct 6, 2010
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Moving the Line
2) Give starters extra credit for additional outs beyond the 6th (or 7th) inning. That could more faithfully measure the additional contribution by starting pitchers in giving the bullpen a rest, as in the example above, but I can't think of a good way to do it.

So what say you, SoSH Nation? Am I already late to the party on this, or is this worth thinking about?
Yeah, you're a touch late on this particular aspect, at least. Game Score immediately comes to mind, and accounts for the depth of a pitcher to some extent, in its original Bill James version, where GS=50 + Outs + 2*(IP Completed After the 4th) + Strikeouts – Hits – 4*Earned Runs – 2*Unearned Runs – Walks. In full disclosure, Bill James didn't really like it, describing GS 'a kind of garbage stat [...] it is fun to play with'.

As a result, Tom Tango made it better last April, although he doesn't count in the inning as a base, and is calculated like so: GST(ango)=Constant + 2*Outs + Strikeouts – 2*Walks – 2*Hits – 3*Runs – 6*HR. The constant basically ensures the average game score in each league in every season is equal to 50.
 

Cumberland Blues

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Sep 9, 2001
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I think I see what you're trying to get at - but I'm not sure how to get there, as I think the way games with a thing 1 and thing 2 breakdown like that are going to slice different ways depending on the starter. Sale w/ a 6 run lead likely gets replaced at the beginning of the inning to save bullets for later. But in a 1 run game where Fister gets replaced by Barnes (or now Reed), I bet Sale starts the 8th. Or maybe this is already sorted out by leverage index? I'd hypothesize that elite starters have a significantly higher leverage index when pitching past the 6th than do journeymen like Fister. Farrell would rather waste Fister bullets than any reliever bullets in a low lev 8th, but assuming the pitch count isn't crazy, he's going to trust Sale more than any reliever not named Kimbrel in a high lev spot.
 

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make hers mark
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Isn't this what WPA attempts to address?
I'll throw in a suggestion for this too, though like Context Neutral Wins (WPA/LI) as well, in addition to RE24 or REW (if you like percentages), if you want to look at how the 24 base states a player can deal with.
 

Gdiguy

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Jul 15, 2005
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San Diego, CA
Although I think the above cover kind of what you're suggesting, there's some interesting questions there I'm not sure I've seen actually answered - basically, what is the value of saving a closer / 8th inning / etc pitcher?

You'd have to go back a few years, but that should be calculate-able... basically what is the win probability gain from bringing in a reliever versus the decrease in win probability from tomorrow's game for having that pitcher not be available? It would be interesting to know what that value is
 

charlieoscar

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Sep 28, 2014
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I just did a correlation of pitchers' winning percentage (based on games they won or lost) to their Quality Start percentage and also to their average Game Score for all pitchers who have tarted at least ten games in 2017.

QS% | pWL% = 0.505
pWL% | avgGSc = 0.708

This is quick and dirty and doesn't take non-decisions into account but I think it shows that Game Score has some meaning. [Source: bb-ref 2017 MLB Starting Pitching/Team Starting Pitching]