Luck of the Pitcher

I think it is pretty common knowledge at this point, that in large part the Tigers pitchers results exceeded their performance last year. If you subscribe to the DiPS theory, that pitchers have limited ability to control whether balls in play turn into hits, then in general the Tigers pitchers got by without striking out a lot of guys because the defense was so good behind them. Part of me wondered it the pitchers still deserved some of the credit. That perhaps they were allowing more “fieldable” balls, thus having better defense behind them.

Well David Pinto at Baseball Musings has answered the question.

Using the probabilistic model of range, which looks at a number of factors (type of hit, direction of hit, hardness of hit, handedness of batter/pitcher) calculates the likelihood that a ball in play with each of those parameters is converted to an out. The summary table below is just for the Tigers starters and contrasts the predicted rate of turning balls into outs (DER is defensive efficiency ration, or the percentage of balls in play converted to outs), and the actual rate.

It’s pretty easy to see that Kenny Rogers, Justin Verlander, and Nate Robertson all benefited from some extra defense – or perhaps extra luck. Kenny Rogers had 18 more balls converted to outs than expected, which is another reason to expect that he might not be as good this year. It wouldn’t necessarily be because he’s older, or even unlucky – simply that he’s not as lucky.

If you look at the last name on the list, Jeremy Bonderman, he got the least help from his defense. Bonderman already has the great peripherals, and with a little better luck could easily shave off enough ERA to become a legitimate Cy Young contender.

On another note, David Pinto runs his blog as his job. He relies on ad income, and donations, for his livelihood. He always produces great analysis and makes the data available for everyone. I use it frequently on this site. Right now he’s running a pledge drive and asking for donations. If you enjoy this type of data, I’d encourage you to click through the link above and drop a little in the tip jar.


  1. Kyle J

    March 14, 2007 at 1:54 pm

    Interesting information. Let’s hope it was more superior fielding than pure dumb luck. We’ve got the same eight starters in the field, so there’s some hope that the defense will continue to lend the pitchers a helping hand.

  2. Brian

    March 14, 2007 at 2:18 pm

    How much would 18 balls really hurt a pitcher? Thats 2/3rds of a game. If he has the expected number instead of 18 extra his ERA MAYBE goes up to 4.20. Is that really all that much worse than 3.84?

  3. David

    March 14, 2007 at 6:26 pm

    The 25.5 approximately extra outs (which doesn’t include relievers or Maroth or Miner etc.) might have really only been a factor in close games or 1-run games. Looking at our so-so 1-run record – 24-20 (because I don’t have time right now to look at both 1 run and 2 run games, sorry), we probably did not benefit all that much from the “expected” vs. “actual” outs.

    I think you have to take it game by game and player by player. Our corner outfielders seemed to have below average range and arms, and Grandy had very good range (except some cases in a ball hit over his head), and an average arm.

    Inge had the best range of any 3rd baseman or SS I’ve ever seen with a gun, but sometimes botched fielding plays, or made an errant throw. Guillen had also one of the best ranges for a SS if you look at assists (but that could also be due to the fact that many of our pitchers made hitters hit ground balls to the left side), and sometimes double clutched.

    Polanco had great positioning and was smart when he got the ball, also accurate arm. Casey wasn’t great at 1east at least in my eyes; Shelton was better and improving each time out. Pudge had great range, a great arm and would block a ton of balls that other catcher might not have.

    Also you have to remember that on our staff we have 3 lefties all of whom have great pickoff moves, and Verlander whose pickoff move was very good. Bondo was the only one who did not have a great move to 1st… I duno it’s kind of confusing…

  4. billfer

    March 14, 2007 at 6:30 pm

    Thinking in terms of run values, an out is worth -.3 runs. If we assume the best and that each of those outs turns into only a single, those have a run value of .49. So if you take away the out and turn it into a single, the swing in runs is .79. Do that 18 times and you’re looking at a little over 14 runs, or about a game and a half.

    In terms of Rogers specifically, even assuming that he still pitches the 204 innings (which probably would have been a little lower), his ERA is now 4.45 which turns him into a league average pitcher.

    Not devastating, but still a real impact.

  5. Brian

    March 14, 2007 at 6:49 pm

    4.45 was about what I expected of him last year though.

    But then there is also the question of pitchers that are consistently lucky every season. If you look at Rogers career in general for example…

    3066.0 ip 3180 h 1079 bb 1850 k 4.19 ERA 117 HBP 309 HR

    I see a pitcher that likely should have an ERA higher than 4.19. With a WHIP of 1.389. My favorite FIP equation is…

    ((13HR + 3(BB+HBP) – 2K )/IP)+3.20.

    If I use that equation I get a FIP of 4.474. Yet Rogers has an ERA .283646 below that, which indicates that he has been a lucky pitcher over his entire career.

    Now does that mean he is lucky or that he has something that the stats are not indicating. Not an easy question to answer.

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  7. billfer

    March 14, 2007 at 10:11 pm

    I think there are some things, like Dave mentioned he takes care of a handful of baserunners with the pickoff. Being a groundball pitcher he might benefit from the double play ball. He may tend to induce more fieldable balls on a pretty consistent basis. Or maybe it has something to do with his ability to field his position.

    Don’t really have an answer, just throwing some stuff out there.

  8. David

    March 14, 2007 at 10:36 pm

    I duno, if you go to baseball reference and neutralize his stats using a 750runs/season average, he should have gone 13-10 with a 3.41ERA, maybe he was alittle lucky but much more before the ASB.

    Before the ASB his record was 11-3 with a 3.85 ERA with a 1.19 WHIP and .256 BAA

    And after was 6-5 with a 3.83 ERA, 1.34 WHIP and .250BAA

    Last year when he left the game, we were ahead by 3 or fewer runs in 6 starts and won 4 of those and behind by 3 or fewer runs in 11 starts and lost 7 of those. Therefore he won a slightly greater percentage of games where he was leading by 3 runs or fewer than he lost of games when leaving by the same margin.

    What this says is that the rest of his record (13-1) was mainly due to blowouts.

    5 games in the first half after we were leading by 6 or more runs when he exited we won, compaired with just one in the second half.

    On a side note, Gary Sheffield might really help our team in the second half. Although we struggeled last year in the second half it has been a pattern for the last couple of years. Last year Guillens average went up month by month (excluding april), and Inge hit around .290 in the second half. Hopefully Shef can really help hold that up.

    His two best OPS months are July and August, .951 and .964.

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