August 3, 2007

I’m with JD: Guevara Can’t Be Worse Than Cormier Was

As you almost certainly have already seen, JD at Red Reporter put up a post about the excellent numbers of Carlos Guevara in AA Chattanooga. He hypothesizes that the reason Guevara hasn't been given the opportunity to prove himself in AAA Louisville is because general manager Wayne Krivsky is a dyed-in-the-wool seamhead who can't overlook the guy's height and lack of plus off-speed stuff to notice that he's getting results.

I have the sneaking suspicion that JD is on to something there. The refusal to acknowledge the numbers is the baffling deficiency of the scout. Surely there must be some middle ground here, where you can follow your gut with due consideration to the numbers.

That being said, observing the actual results isn't exactly the strong point of the statheads either. The obsession with removing luck from the picture discounts the very real part that luck plays in the game.

Perhaps a simulation of each key personnel decision in Celebrity Death Match format is in order.

4 comments to “I’m with JD: Guevara Can’t Be Worse Than Cormier Was”

  1. JinAZ says:

    [i]The obsession with removing luck from the picture discounts the very real part that luck plays in the game.[/i]

    Hmm, if I can be a bit narcissistic here, that sounds directed at me…or at least people like me.

    The reason that people like me try to identify the proportion of a player’s (or a team’s) performance that stems from luck is not an effort to ignore how luck influences performance on the field. If anything, it’s an effort to better appreciate the importance of luck–I think our efforts have shown that luck plays a far more important role than is generally appreciated by a lot of fans, analysts…maybe even players.

    What we’re after when we do try to identify and remove luck from player performance is prediction. We want to separate player skill from the fortunes of the player, because if a player is doing well (or not) due to their skill, that player is likely to continue doing well. But if a player is doing well (or not) due to luck, that player is less likely to continue to perform in that manner. Isn’t that something worth knowing?

    As an alternative to those efforts, there is also a line of work that attempts to document in greater detail than ever before how games are won: win probability. This line of statistics explicitly rewards performances that come at times when they can influence ballgames. Drive in a run in the bottom of the 12th inning of a tie ballgame? You get massive credit. Drive in a run in the bottom of the 6th with your team down by 10 runs? You get very little credit. Therefore, I’d argue that this line of statistics celebrates the role that luck and timing have on ballgames in a way that classic statistics cannot…and this documentation can be useful, because it can help us better understand how teams have won in the past.

    The fact that things like a historical tendency to perform better in the clutch does not tend to result in better future performance in the clutch does not mean that those clutch performances were unimportant. It just means they don’t tell you much about what a player will do tomorrow. And again, I think that’s worth knowing. -j

  2. Red Hot Mama says:

    Hiya J. Long time no see!

    Nah, it wasn’t directed at you particularly, but I’m glad to have your opinion. And I agree with the stuff being worth knowing. That’s what I was getting at when I talked about finding a balance between trusting your instincts with due consideration for the stats.

    I’d be less concerned about a players who’s doing well due to luck than one who’s doing badly because of luck. If the Reds were considering signing a free agent who’s had a crappy record but who had also suffered a lot of bad luck, I’d recognize that there’s the possibility that he’s a steal. But I’d also recognize that maybe there’s a reason he had bad “luck” and that reason might continue.

    In my mind, the fact that the reality team failed to get the job done behind him outweighs the fact that the theoretical team should have gotten the job done behind him, and I’d be willing to pay less.

    But, like I said, I don’t see that these philosophies can’t co-exist. It’s just a matter of deciding how to implement them together. Perhaps “win probability” is a step in that direction.

  3. BubbaFan says:

    Interesting example in the Bronx right now: Shelley Duncan (the son of Cards pitching coach Dave Duncan). Neither the stat guys nor the scouts were enamored of him, despite the fact that he was raking in AAA.

    Supposedly, in the scouts’ minds, Duncan was kind of a joke. They rolled their eyes at the fans’ enthusiasm for Duncan’s gaudy numbers. They said Duncan was a hitter who lived off mistakes in outer half of the plate, and once he got to the big leagues, where they’re not afraid to come inside, he’d be exposed.

    Meanwhile, the stat guys weren’t too enthused about him, either, because he was 27 and had yet to crack the big leagues.

    The Yanks eventually did call him up, basically out of desperation. So far, he’s raking:

    .321 .406 .857 1.263

  4. KC2HMZ says:

    What about Jeff Keppinger? From a scouting point of view, he’s basically lacking in four of the five tools scouts generally look for. Stats guys tend to be more impressed with players who have a high OPS, and Keppinger isn’t a power hitter so he’s not going to have a high OPS.

    Yet right now, if the Reds have the bases loaded there’s nobody on that roster I’d rather see at the plate than Keppinger.

    But don’t take my word for it. Just ask the Brewers. 😎