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Saturday, December 20, 2008
And more on positional adjustments
For those new to this concept, I posted the following at a good exchange at Primer:
Good thread, the kind of thread that attracted me to the old Primer. I’ll just reply on those that directly referenced me, and then I’ll make another post later for the rest of the thread.
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So a team full of Willie Bloomquist would be utterly average?
As fielders, yes.
It doesn’t necessarily have to be Willie. It’s always nice to have a real face to the issue. Willie plays all the positions, and he looks average, and he has overall, pretty average numbers. Plus, my readers voted him the worst player in baseball two years ago, so I have a special affinity for this guy. If you want to use someone else, Melvin Mora, or whoever, feel free to bring a better name forward. I used to call this player “Hubie Raines”, in honor of Hubie Brooks and Tim Raines.
This was first brought forward in 2003/2004, and one of the first articles on the subject is here:
http://tangotiger.net/UZR9903TT.html
My blog is filled with such “multiple position” comparison. Only recently have I included the lefthanded issue, which brought the CF down a peg, and in-line with 2B/3B.
I’m probably missing something, but lately it seems like the people who are working with defensive numbers are treating them more like gospel than they deserve to be treated at this point.
I go out of my way to say that they are not gospel and that lots of work needs to be done here.
I think anybody who starts promulgating a new stat has the duty to explain why the stat has value and how it came to be calculated.
I “promulgate” on my blog. If you think more people should cite their references more, you should take it up with them. In this case, you should shoot the messenger! Seriously, as Bill James once said, if it sounds like you are walking into the middle of a conversation, it’s because you are. It would be nice if we have everything in one spot. It’s just not always possible for us amateurs to find that time to get everything summarized.
I am ready to be convinced, but the argument Dave makes and others convinces me more that it isn’t correct.
A good article and followup can be had here. We just need some time. I know I would enjoy the discussion with Chris and Dan R and several others.
Now, let me comment on the rest…
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VORP is adjusted, yes, but it is only adjusted to normalize offense across positions, not defense as well.
Untrue.
The idea behind what VORP does is to “neutralize” the offensive disparity among positions so that you can simply add in the fielding value relative to position (which is what SuperVORP is). The end result is that you don’t have a positional bias.
Otherwise, if you simply do: offense above average (without regard for position) and defense above positional average, then the average 1B will be far higher than the average SS (by some 20-25 runs or more).
Chris with OPD (offense plus defense) ensures that the average at each position is exactly equal. He does that because his presumption is that a position is a position, like QB, RB, DT. I don’t do that because baseball players are alot more fluid in their movement, like Left Defensemen and Right Defensemen, or Left Wing and Right Wing in hockey. No one in the NHL would measure Centers against other Centers. You WOULD do Forward against Forward. So, you really have “pools” of positions: C, IF, OF, 1B/DH. (In baseball, the pool on the right includes the pool on the left.)
Anyway, like I said, we can have a long discussion about this.
The problem. however, is that there’s an implicit assumption in doing things that way that the sum of the defensive differences between any two positions are equal to the offensive differences within a given year. That just is hardly ever true, and leads to incorrect valuations of players.
Right, my position entirely.
LF will never be equal defensively to CF. 2B will never be equal defensively to SS. When the metrics miss this important difference, they’re wrong.
People may also be surprised to know that the average RF hitter was WORSE than the average CF hitter in the 1950s. Would it make any sense that the average CF (off+def) equals the average RF in this case? You’d have to believe that the average RF was a better fielder in the 1950s.
To say nothing of when Brian Giles gets the bad luck of having Barry Bonds in his NL LF pool, and the next year he has the good luck of not having him in the NL RF pool.
And if you consider the DH/1B issue?
How about high school? Would you want the average SS there to be equal to the average 2B? OPD sets that as a requirement. Now, Chris may say that the SS from one team is competing with the SS of the other team. But, when he makes his list, he includes all players, and so if you have an average high school SS and an average high school 2B, they both come out equal in Chris’ list.
That’s why I can’t go along with positional adjustments that make it a requirement that the average at each position is always identical under all circumstances.
What we’re talking about here is rigid and inflexible, based on the conceit that value is based on some absolute difference in difficulty.
These adjustments apply only to the time period it was based upon (2003-2008). If for example the 1970s was filled with a ton of fantastic fielding SS, I’d have different adjustments. So, Dan’s presumption here is in fact not a presumption of my system.
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If there’s anything else that I need to directly reference, please let me know.
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In summary, I ask the question: “How does this player field compared to Willie Bloomquist, or some composite who is average in all tools respect (speed, strength, agility, etc), and who is equally experienced at all positions?”
Since this is the common baseline that we are comparing all baseball players against, we can make the apples-to-apples comparison. And that’s what those positional adjustments do.