How have players who've changed positions from catcher (like Joe Mauer and Carlos Santana) historically tended to do?
One of the favorite storylines this time of year is the positional change, whether it’s putting on an entirely different kind of glove or just moving over a few dozen feet to the left or right. Predicting performance changes is hard, but a positional change is something we can see, so it’s something we can write.
One of the least-favorite storylines—or at least most confusing—is when a positional change comes with a promise that the player will be able to improve on offense because he can spend more time working on it.
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The Tigers are testing the old adage that you can never go back again by shifting Miguel Cabrera back to third base, but is there any precedent to suggest that the move might work?
All players eventually succumb to the passage of time. Outwardly, though, some age less obviously than others. Their statistics might lose some of their luster, their managers might rest them more often, and they might be more susceptible to a calf pull here or a hamstring strain there. But they look no less trim and move no less smoothly than they did in more durable days. Watch them from the stands, and you might almost convince yourself that they’re still in their prime and not deep in decline.
Look at early-model and late-model Mariano Rivera. It’s tough to tell them apart. Here’s Rivera giving up a crucial home run to Sandy Alomar Jr. in Game 4 of the 1997 ALDS. (Orel Hershiser, by the way: also aging gracefully.)
Sorting out some positional issues on the Yankees could take a different turn if interior defense is the salient issue.
One area in which the present really shouldn't compare poorly with the past is in legend-making. However much how the story gets told might be different, we still have heroes on the diamond whose reputations transcend what they do and how well. Nowhere is that more apparent than in the case of "The Captain," obvious Yankee great Derek Jeter, future Hall of Famer.
A long-running debate over Jeter's virtues as a defender has been a basic touchstone of the sabermetric landscape for almost as long as Jeter has been a major leaguer, and assessments of his value with the glove mark one of the most startlingly specific divisions between analysts and scouts, between performance and anecdotal observation, between documented statistical evidence and reputation. In his prime, the argument was relatively pointless, as Jeter's tremendous position-relative value helped power the last Yankees dynasty. When Jeter was able to provide a Wins Above Replacement mark of 6.9-a mark that includes his defense-as recently as 2006, the debate was puerile, if not downright academic. Ask any GM if he'd like a seven-win player at shortstop, and he'll say yes. Players this good, statistically or in the flesh, don't grow on trees.
Nate recovers well enough from Chicago's Super Bowl loss to share PECOTA's take on first base prospects.
Fortunately, writing about first base prospects gives me something of the day off, since there aren't very many of them. A lot of this flows from sabermetric first principles; first base is the endpoint of the defensive spectrum, which not only means that you have to hit a whole lot to make a name for yourself at the position, but also that there's nowhere to go if your defense gets any worse.
Keeper league owners need to start thinking about who they're going to hang onto, and grasping positional scarcity for next year holds the key.
To an extent, it makes sense to worry more about position scarcity in the offseason after personnel moves between leagues and offseason position switches (as with Miguel Cabrera this year) have taken place. One advantage of looking at scarcity at the end of the season, rather than at the beginning of it, is that it takes the guesswork of projection out of the equation. Coming into 2006, for instance, shortstop was expected to be a fairly deep position in the American League. Disappointing years from the likes of Michael Young and Bobby Crosby, among others, made the reality something different.
A closer look at the validity of one of BP's best-known theories.
Everything in prospect analysis is relative. Pretty much everyone agrees that some discount needs to be applied to pitching prospects. Baseball America isn't treating Mike Pelfrey like he's Justin Upton, and rest assured that we wouldn't trade Matt Cain for Trevor Plouffe. But figuring out exactly what the discount rate should be is something that hasn't really been resolved. Traditional prospect analysis almost certainly isn't discounting enough, and I've come to believe that Baseball Prospectus isn't discounting enough, either. Although the amateur draft has seen a substantial correction--perhaps even an overcorrection--pitching prospects are still treated in trade talks like they're black chips at the Bellagio.
How should we re-evaluate players who've started the year on a tear, or in a rut? As ever, PECOTA has an answer.
Two seasons ago, I established a method to revise PECOTA projections on the fly by combining a player's PECOTA percentile forecasts with a binomial distribution to come up with a revised estimate of a player's "true" level of performance. The method was described in a lot of detail in the article that I've linked and I'm not going to describe it again here (plus it's late and I'm tired: do you know what your favorite baseball columnist is doing at 5 in the morning?). Long story short: this method is designed such that we have an effective way of gauging just how much an unexpected early-season performance should have on our assumptions about a player's long-term value.
You wouldn't think that Doug Mientkiewicz would have something in common with Hank Aaron and Mickey Mantle. That's why we keep Steven Goldman around.
This is, of course, not the first time that a team has implemented an unskilled/skilled transition during the season with little advance notice or preparation. Some of these moves worked out quite well. In 1968, Detroit Tigers center fielder Mickey Stanley moved to shortstop so that Ray Oyler's .135/.213/.186 averages could take a well-deserved seat on the bench (baseball rule: all shortstops named "Ray" or "Rey" cannot hit), a move that led directly to a Tigers championship. In 1986, the Chicago White Sox relocated future Hall of Fame catcher Carlton Fisk, 38, to left field for reasons never explicated, probably because they were poorly understood (Ron Karkovice?). There were statues in the Louvre more mobile than Fisk and the experiment was officially abandoned soon after.