One thing I notice (which may or may not have any significance), is that the position adjustments for all positions excluding DH sums to 0. This seems to make sense–the position adjustments are “normalized” in some sense, so that you’re not under- or overvaluing players in general.
Once you include DH, however, that falls apart. Does this mean that after applying positional adjustments, we have a net undervaluing of all players? Should positional adjustments be normalized differently in the AL and NL to prevent this?
Dave, I obviously love that you’re talking about this. And you do a great job of explaining it well.
One thing that might deserve clarification — why do teams stick Burrell/Dunn/etc in LF instead of CF? There IS some inherent difficulty difference between LF and CF, which is why the better defenders get stuck in CF. Or, if you don’t like to talk in terms of difficulty, you could say that CFs have more opportunities to show off their skills — more balls are hit their way.
One problem with normalizing AL and NL position adjustments differently is that it would become more difficult to compare players across leagues, so that doesn’t seem like a good solution.
Relatedly, if position adjustments were renormalized to prevent undervaluing, we have to keep in mind that there are fewer DHs than players at other positions. So to prevent overvaluing, we wouldn’t want the position adjustments to sum directly to zero, instead, the weighted (by the number of positional slots) position adjustments would sum to zero.
All of this assumes that this is even relevant / a problem.
Right, I’d phrase it in the latter way – teams hide players at positions where they’ll have the least amount of opportunities to display their awfulness. They play LF instead of CF because LFs get fewer chances to screw up.
I wouldn’t say CF is harder to play than LF, only that the extra opportunities magnify defensive abilities, both good and bad. And for lousy defenders, magnification of that lousiness is not what teams are looking for.
One thing I’d like to know is, how much value does Crawford gain by being in center field? I would guess not as much as most people think. The position adjustment and the increased competition should cancel out so the only thing adding value is the amount of balls he gets. So I guess I’m wondering what the increase would be in balls in his zone, and how much value does that actually increase? How much value does Manny lose if he gets moved to center?
Comment by lookatthosetwins — December 17, 2008 @ 4:25 pm
Assuming league-average talent at a position (well, maybe right in-between the average of the two positions being considered) and a league-normal skillset, there shouldn’t be much benefit or cost to moving a player, beyond the learning curve.
But as players get much better than positional-average, moving them to a tougher position allows them to show off more of their skills, because they receive more opportunities. And moving crappy fielders to “easier” positions is a good move, because their gap below average will shrink. It’s an absolute change versus percentage change thing. The further you are away from zero, the more a percentage change will matter.
Shouldn’t SS defense be more valuable that 1B defense in part because of the number of balls that the player is eligible to field?
I would think that this is the primary reason that CF is considered a defensive “premium” position while the others are not. (Since a CF will see twice as many play opportunities each 1% difference in the rate at which he makes plays counts twice as much in a sense.)
How does the rate at which balls enter the region where a field could get them affect defesive adjustments and the value of defesive abilities?
Comment by philosofool — December 17, 2008 @ 6:50 pm
How do you arrive at the -17.5 runs for the DH? I’m a little unclear on how you establish the positional adjustment for a player that doesn’t play defense.
We start by figuring out where DH’s come from. In pretty much every case, a full time DH is a miserable defensive LF or 1B. The guys who end up as designated hitters are guys who couldn’t hack it in the field. Therefore, we know that the DH population has to be a subset of bad defensive first baseman, and therefore, will be worse defensively as a group than first baseman. Therefore, they have to be worse than -12.5.
So, if we look at the performance of DH’s when they play 1B, they’re usually something like 10 runs worse than average as a group. That would make the positional adjustment -22.5. However, we bump it back up to -17.5 to account for the fact that it’s harder to hit while DH’ing than it is while playing the field – the evidence for this is in The Book by Tango/Lichtman/Dolphin.