Tuesday, January 26, 2010

Jeter, Rose, Rodriguez & Record Projections

The question of whether or not Derek Jeter will pass Pete Rose's all-time hit mark is not a new one. From what I can find on these here internets, Rob Neyer addressed the possibility in a mailbag back in 2006 as Jeter was approaching 2,000 hits and was, like he is now, slightly outpacing Rose based on seasonal age and number of hits accumulated. It came up again in 2008 as he neared 2,500 hits and probably a few times in between.

Since then, essentially nothing has changed except the people who bring up the question - usually not bloggers but relative outsiders who haven't heard it discussed ad nasuem already. Back in that 2006 Neyer mailbag it was a reader named Yehuda Hyman and yesterday it was the pinch hitter at LoHud named Lucas Vanderwarker. Lucas's post got picked up over at Baseball Think Factory and Neyer got in on the action again, adding some new relevant assumptions to the equation:
Now, let's think about how Derek Jeter's career is likely to play out. One, everyone seems to think that Jeter will retire as a Yankee; that they'll do anything keep him around and that he won't be interested in playing elsewhere. Two, he's a shortstop. There's essentially no such thing as a 42-year-old shortstop. Three, the Yankees have Mark Teixeira under contract through 2016, when Jeter will be 42. They've also got Alex Rodriguez under contract through 2017, when Jeter will be 43.
David Pinto also chimed in, offering up Robin Yount as a comparable who, as a 35 year old was over 100 hits ahead of Rose but played only two more seasons and finished with 3,142 in total.

As Rose said Joe Posnanski, "You tell Derek the first 3,000 are easy". Of course, the implication is not that they're actually easy, but they're a lot easier than the next 1,256, which, as every other person ever to have played the game has figured out, is a true statement.

Jeter is 35 and a half years old and although we've seen very few indications to the contrary, the Cap'n is not invincible. No one is.

I learned this the hard way last year when I took issue with Nate Silver's projected home run totals for Alex Rodriguez, which predicted he'd end up with 730. I eventually ventured a guess as to what his career home run tally would be. I used an exhaustive 8 step methodology and arrived at the number 792. That involved a prediction of 42 for the 2009 season.

Much to my chagrin, not even two weeks later A-Rod was out in Colorado having surgery to repair a torn hip labrum, missed over a month of the season and had to hit two home runs in the same inning in Game 162 just to reach 30. Not only that, but his hip injury also cast serious doubt on his long term health.

While it's still a distinct possibility that A-Rod breaks Barry Bonds' Hank Aaron's record, it doesn't seem nearly as likely as it did just a year ago. But the picture is a lot rosier than it was the day after he had surgery. And that likelihood will probably fluctuate countless more times before he either breaks the record or retires.

I understand why fans like to talk about these far-flung possibilities and we are outrageously lucky to have two players on the Yankees pursing perhaps the two most hallowed career offensive records in Baseball. But at the same time, I'm not interested in reassessing what a projection system - using a bunch of players as comparables who, by definition didn't break the record - predicts the odds are that A-Rod or Jeter will reach that milestone every time one of them passes a round number, gets injured or the offseason news cycle grinds to a halt.

Projections can be a very useful tool in the right context but these kinds of records get broken on a very infrequent basis and only then by extreme statistical outliers. And besides, the left side of the infield still has a long, long road ahead.

1 comment:

  1. I had a little time on my hands, and ran something similar to what you did last year. Looking mostly at home run totals, I recorded the numbers that Aaron, Frank Robinson, Griffey, Mays, Ruth, Killebrew, and Thome put up from ages 33 through 41. As has been said, the issue is the lack of the players that approach A-Rod's ability/production and the effects that modern conditioning will have on durability. Anyway, using the best-fit line solely established by those players' homers, A-Rod will end up with ~773 home runs (37 in '10, followed by 33, 30, 26, 23, 19, 15, 12). If you incorporate Rodriguez's stats since his peak of 57 HR in 2002, he will end up with around 768 (32, 30, 27, 25, 23, 20, 18, 15). I wouldn't put money on it, though.