I know. That's what I'm worried about.

i wouldn't be real too surprised if youse get stuck with jeter until The Icon decides to retire. see biggio/cal ripken. even IF you could replace him with tulo

The Yankees can certainly live with Jeter as a -10 SS

They are not direct comps but Jeter and Paul Molitor are similar type hitters. Paulie really enjoyed the DH spot, and I suspect Jeter would do well in that role also as mostly DH and every so often taking the field.

By your analysis, Jeter is letting about sixty balls through to the outfield, right? How many runs is that normally expected to lead to?

I suspect Jeter would do well in that role also as mostly DH and every so often taking the field.

It's odd, I know. But could you please explain how the advanced metrics could be missing ~30 hits per year?

Anyone who doesn't think that being relieved of the constant burden of playing a critical defensive position might not have a salutary impact isn't thinking clearly.

But aren't they reviewed on film?

Anyone who doesn't think that being relieved of the constant burden of playing a critical defensive position might not have a salutary impact isn't thinking clearly.

So my guess would be that NYY SSs should have had something like 450 assists, or a shortfall of about 45 assists. Each one is worth about .7 runs, so that's maybe -30 runs

Is that really correct? A single (and all the non-assists made by Derek Jeter would be singles) is worth 0.7 runs?

It's not a single, as much as it is a single that *should* have been an out.

If this is true, and you could demonstrate the mechanism, that would be a great study.

For UZR the mechanism is less obvious, and any impact on other fielders would depend on the source of the error. But if the balls hit in the vicinity of Jeter are being rated harder to field than they really are, that likely means some of them are being rated as possible plays for the 2B or 3B, which would lower their respective UZRs. However, there might not be a huge impact, if scorers are rating a lot of these Jeter misses as being almost unfieldable by any infielder.

Another consideration is whether other NYY fielders change positioning to compensate for Jeter's weakness. It might make sense for A-Rod to play closer to the hole than usual, for example. That could be the right move for the Yankees, but still leave him with a low UZR in comparison to other 3B.

Right: a missed play is trading an out (-.25 runs) for a single (+.45).

As others have mentioned, there's barely any full-time DH's who are stars. Big Papi and Vlad (1st year as full-time DH), and Matsui are pretty much it for this year

If someone with access to the BIS data could show that the Yankees are consistently allowing an atypically large number of ground balls to the SS/3B and 2B/SS holes which are rated as unplayable or practically so, it would support the theory.

The Yankees may just think this is the best way to play the infield in general.

Well, we already know that the BIS data is saying Jeter has far fewer fielding opportunities than the typical SS, and says this year after year. That's a mathematical certainty -- there is no other way for a player to make so few outs yet get a decent UZR rating. The only question is how much that affects the opportunities assigned to Cano and A-Rod.

Are you suggesting the Yankees have found a new way to position their SS that is good for the team, but results in his making 60 fewer plays each year than a typical SS? This seems very unlikely -- as Dial has often argued, there just aren't enough GBs in areas of shared responsibility for players to trade off responsibility for zones in this way. Or are you saying the Yankees position him badly, so his poor defense is really management's error? (More plausible, though not by much.)

I guess it's possible that A-Rod lacked certain 3B skills that he didn't need at SS, though I'm not sure what those would be

Your theory requires play-by-play data to be quite massively compromised.

What can't be true, though, is that Jeter is a nearly average SS and yet makes 50-60 fewer plays than average while his adjoining fielders are close to average.

defensive statistics are often weird

It's really not conceivable that scores of Yankee pitchers over 16 years have allowed far fewer GBs to SS, but an average number in the vicinity of both 3B and 2B. Well, nothing is impossible. But if the choices are that vs. someone has made mistakes in PBP scoring and/or computations of fielding metrics, the respective probabilities are something like 1% and 99%.

Maybe they could bring in some 90s tech and superimpose a grid on the video.

In the end, for 2011 at least, they're probably going to have to lump it. Jeter stays at SS for 120-140 games and another 15-20 at DH; AROD stays at 3B for 120-140 games and 20-30 at DH; Posada is at DH for, oh, 90-120 and catches 30-50. They need to find a new starting C and a decent SS/3B backup.

Once Posada's off the books, AROD to DH and Jeter to 3B.

You know what occurred to me the other day? I think Jeter would be a shitty manager. I don't know why I started thinking about this--but I doubt he will ever be a manager of any kind. Maybe some kind of other front office gig. Jeter is an instinctive player. I've never heard him make an intelligent point about baseball. Not that he's not smart, but I just don't see him as a deep thinker about the game.

And we have continually growing evidence that the BIS data is compromised - not just their hit location data, but their hit trajectory data (GB/LD/FB), their pitch type data, their pitch location data... the whole nine yards.

MCOA: One reason we may be talking past each other a bit is the distinction between seasonal stats and career stats. I'm not making any claim about how accurately one can measure defensive performance from raw stats at the season level. But with Jeter we have 16 years of data and over 60,000 BIP. For someone like that, I think there is a practical limit in terms of how unusual their distribution of opportunities can be.

You, like GuyM, seem very confident that positioning and ball distribution can only have a certain proscribed level of effect on plays made by a defensive player

As for the batted ball distribution - where is the evidence for the other position, that such a radical distribution of batted balls is sustainable for 16 seasons?

Maybe they could bring in some 90s tech and superimpose a grid on the video.

Everyone (and most defensive systems) seems to agree that Jeter's defense at its worst has been horrible, that he's probably been easily the worst defensive SS in the game for long stretches of his career....Guy seems to be going far, far beyond that. Is Guy's position reasonable, though?

GuyM has suggested the effects of ball distribution, even over a long career, might account for up to five runs per year. I'm wondering why five, why not two or ten or twenty?

I have a pretty strong presumption that professional baseball people are not wildly incompetent, and it's hard for me to believe that everyone has been this wrong about Jeter's defense. It could happen, so I guess it's not outlandish, but I think it's really unlikely.