Before I begin, let's discuss a fundamental element of pitching statistics. As we discussed previously, there are some statistics that normalize slow, but consistently, and therefore tell us about luck. Batting average of balls in play (or BABIP) is one of those, so is home runs per flyball (HR/FB). Basically, one out of every ten fly balls lands in a fan's greasy palms. There tends to be very, very few exceptions to this rule. And since I have a degree in English, I loathe using the word very, so note how I used said word twice in the last sentence. It means I'm incredibly serious. Few people ever escape HR/FB normalization.

So basically, with this knowledge (that every pitcher has around a 10% HR/FB), we use the expected fielding independent statistic (xFIP) which looks at how a pitcher would perform given a normal (10.6%) HR/FB ratio.

Yesterday, Lou Piniella and Jim Hendry -- and even Tom Ricketts okay'd this -- moved our pitcher, Carlos Zambrano, to the bullpen. To be a setup man. To pitch at most 70 innings for the rest of the season (assuming the move sticks). As a setup man.

Meanwhile, other "bloggers" have rejoiced in the suddenly resurgent or former mercurial pitcher Carlos Silva, even going so far as to propose (hopefully in jest) that Silva's name should ring among halls of Lincecum, Greinke, Sabathia, and Young. Before I begin to bleed from my eyes, let's examine the statistics behind this move to the bullpen.

I love this game, and so we're going to play it: I have two pitchers, Carlos and Carlos. Which one of these pitcher should I try to use as much as possible, and which one should I shuffle away into the bullpen?

Career  FIP: 4.54
Career xFIP: 4.47
2010    FIP: 3.08
2010   xFIP: 4.05

Career  FIP: 3.96
Career xFIP: 4.09
2010    FIP: 4.73
2010   xFIP: 3.39
It's not a clearcut, easy decision. The first Carlos has shown an averageness in the past, but the second Carlos is showing an averageness in the present. THE KEY ISSUE IS THE xFIP! The second Carlos has been, how you say, a feces-ton unlucky in 2010, whereas the former Carlos has been a feces-ton fortune. I have highlighted the xFIP just to make this perfectly clear.

SURPRISE! (This is the fun part!) The second Carlos is none other than Big Z! The first is the occasionally recalcitrant Carlos Silva!

Earlier this year, Cubs beat reporters, perhaps out of some backlash from their unreasonable Milton Bradley hatred, went ga-ga over Silva's bullpen session with Larry Rothschild. After the session, Silva said it felt like his sinker had finally returned and he could now pitch like a champion again! (Yeah, maybe not that much enthusiasm or delusion.)

So, as a now-fixed sinkerball pitcher, we fully expect Silva to see his groundball rate (GB%) skyrocket! Let's take a look:

Source Fangraphs.

Um, that green line, that ultra important line for a guy like Carlos Silva, is sharply down-sloping. And the blue line, the line that correlates directly with home runs, it's higher than ever. In the words of every action movie:


Silva is poised for a painful regression while Zambrano is poised for an all-smiles regression -- but now people will falsely think: "Hey, y'all, look at that! ZOMG, Lou dun fixed our angry piture!"

No. False. Not at all. Silva needs to get to the bullpen as fast as possible before his gravy train derails, and LOU MUST UNDUE THE FOLLY OF PULLING ZAMBRANO FROM THE ROTATION IMMEDIATELY, assuming he still cares about 2010.

Honestly, I really hopes this works out for the best. I really hope Silva does win a Cy Young Award, and I honestly would love to see the Cubs reach and dominate the playoffs. I just ultra-mega-really doubt that's going to happen. Especially now.

I would like to close this topic with a post from our friends at Another Cubs Blog:
Here is a list of things I don't understand. I completely made up all except one thing on this list, because you really can only make this shit up.

I have a good friend that only uses the lowest gear on their bike when he is speeding downhill. They are always late for some reason.

When I was a kid, a friend of mine used to keep his coolest toy in the toy bin so the crappy toys wouldn't feel lonely. He was never quite as fun as I think he could have been.

I am close to someone that didn't take their best job offer because they wanted to "save" their money until they got older. They're in grad school now.

There's this researcher I know that never published their best work. They hoped that to lower expectations so that when they finally publish this stuff it would seem brilliant by comparison. They got scooped.

I also know someone that doesn't go on dates with anyone. Their hope is that they'll be able to call these people up one day when they're lonely and really in need of a date. That person is very angry.

Similarly, when I was teaching, I knew a student that never gave their best answer on multiple choice questions because they didn't want to waste all their good answers when they were young. They didn't pass that class.

I also have a LOT of friends that cheer for a team that intentionally decided to bench one of their best players because the team's bench wasn't very good. They still haven't seen their team win the championship...

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  1. I didn't realize until today that Zambrano's babip and hr/fb rates were so high. I generally don't look at statistics until the end of May or so. Those rates make this move even more puzzling.

  2. Nice write-up. You even managed to use 'recalcitrant' and 'mecurial' to describe the great Carlos Silva.

  3. Thanks, Anon; I had the fine folks at ACB in mind while doing that.

    @mb: yeah, I usually don't bother looking at that until later, but this was a special case that really warranted it.