Update: For all the WPA haters, I did the same thing with VORP here.
There are many problems with the MVP award. The main one, of course, is these guys. The second constant issue is the term "valuable". Everyone has their own definition of the word, which makes things quite difficult. Can it come from a guy on a losing team? What about if there are multiple candidates on the same team- does that make the individually less "valuable"?
The way I see it, WPA was created for this debate. The Win Probability Added definition from Wikipedia: "[WPA] is the difference between the Win Probability when the player came to bat and the Win Probability when the play ended."
Well that seems like a pretty good way of analyzing the situation, doesn't it? A measure of how much a player contributed to his team's chance of winning the game- that's just what we're looking for. So let's just look at the WPA leaders, and be done with it, right?
Of course, it is not nearly that simple. As far as I can tell, there are three main things that WPA does not account for:
-Positional value. Having a shortstop who hits .335/.420/.530 is a whole lot more valuable than having a first baseman with the same line. VORP accounts for this, but the WPA numbers listed on FanGraphs do not. To deal with this issue, I developed a system that takes position into account. The positional adjustments, per 600 PAs, are on the right.
-Park factors. Another thing that is considered by VORP, but not in traditional WPA. This is also pretty simple to take into account as I have looked at previously. Here are the per 600 PA adjustments for parks with the most dramatic effects:
-Fielding. Oh boy. Any system trying to account for fielding is going to be imperfect, but it would be unreasonable not to include something. I've used the Hardball Times' fielding stats that were released at the end of August, as well the UZR numbers that MGL released around the All-Star break. Since this is obviously far from complete, I also included UZRs from '05 and '06.
So now we have accounted for the three main inadequacies in WPA- positional value, park factors, and fielding. The only other adjustment needed is a small one, accounting for the leverage of the average situation the batter has come up with, in order to control for hitters who have come to bat in an inordinate amount of "high leverage" situations. All of these adjustments can be seen in the various columns below.
Finally, we can apply all of this to this year's MVP races. Let's start with the straightforward one:
Rodriguez starts off with a huge lead in raw WPA, and does nothing to relinquish it. I think we tend to forget that Yankee Stadium is actually a pretty significant pitchers park, which helps him here. Also relevant is the fact that although he it taking a slight hit for his position, it's not nearly as much as RFs Ordonez and Guerrero.
I think the top four are pretty much what you would expect (although it's interesting that almost half of Ichiro's value comes from his fielding). Polanco, though, is probably not someone that would be expected to show up on this list. He really does belong here though. All of the numbers agree that he is an excellent fielder. More importantly, he's hitting .340/.389/.459 as a second baseman, which is quite impressive. If you put Polanco in pinstripes and throw a "2" on his back, he's in every MVP discussion. Of course, that's now things work, so he'll have to settle for being on this list.
Now, for the interesting one:
I understand that the names not on this list may be more interesting to talk about than those which are, but I'll get to that in a second. Interesting to note that all four of the top NL guys get huge boosts from their fielding. This is because the NL is so bunched up at the top- there are 9 guys within 1.2 of the WPA leader. When that happens, getting an extra 14-18 runs from your fielding vaults you right to the top.
Wright and Utley are neck and neck, and the winner will be decided over the final weekend. Wright suffers a little from the positional adjustment, but gets a boost because Shea is so tough to hit in, and obviously gets a huge boost from his fielding (THT's stats have him at +28 runs).
It's too bad that Utley missed so much time, because he's really had a remarkable season, both with the bat and the glove. The only blemish on his line is the park adjustment, and that's obviously not his doing. Because of the time he missed I didn't expect him to do so well in this analysis, but that just shows how good he's been when healthy.
I talked about Tulowitzki yesterday, so I won't get into that again. Interesting thing about Pujols is that he gets killed in the positional adjustment, but he makes it up (and then some) with his fielding prowess.
OK, now for the three guys who didn't make the top five, but have been included in most discussions:
Prince Fielder leads the NL in WPA. He then loses almost 22 runs because of the position he plays, and how poorly he plays it. That's the thing about this system- you can't just be a good hitter and have that be your entire candidacy. Fielder's only value is in his bat, and you would have to have an overwhelming year at the plate to be the MVP while playing first base poorly. While obviously impressive, Fielder's 2007 offensive campaign doesn't fall under the category of "overwhelming".
Holliday is somewhat similar, but his weakness is the park he plays, rather than his fielding skill (or lack thereof). He's been good (and those 131 RBIs are going to be real tough for the voters to pass up if the Rockies somehow sneak into the playoffs), but he really doesn't belong in the MVP discussion.
Rollins is definitely the most interesting omission, as he would have to be considered the co-favorite at this point (along with Wright) to win the award.
Is this really even worth discussing? As far as I can tell, the main thing in Rollins' candidacy is this stupid 20-20-20-20 thing. Who cares? Can we talk about how the guy walks less than half as often as Wright, while having a lower slugging percentage and getting destroyed in BA, rather than his possible inclusion in some gimmicky club?
The two factors that this table doesn't show, but I've included before, are fielding, and position. Rollins obviously has the positional value thing on Wright- with this huge number of PAs, there's about an 11 run difference between SS and 3B. But none of Rollins' numbers indicate he's anything other than an average fielder, while all of Wright's 2007 numbers are stellar. I just don't see how Rollins even comes close to making up the huge gaps in the hitting categories.
So there you have it- A-Rod takes it in the AL, with Utley and Wright battling it out down to the wire in the Senior Circuit. The official MVP award is quite different than this- it focuses mainly on batting average and RBIs, while ignoring useful batting statistics and fielding. It also won't be announced until mid-November, when everybody will be preoccupied complaining about the BCS anyway. Much more timely, fan friendly, and intelligent will be the Internet Baseball Awards, which you can vote on over at BP after the World Series ends. To give you an idea of how things work over there, Morneau finished 6th in the AL voting last year, which is probably all the proof you need that it's a superior system to the actual award.
Photos: Wright, A-Rod, Utley, Rollins.
Update: After reading the BBTF Discussion of this post, I wanted to mention a couple things I should have included.
I should have mentioned that UZR is screwed up for Coors, as MGL mentions in the comments of the post in which he released them. UZR had Tulowitzki at +14 runs through the ASB, which is probably too high. He is probably slightly overrated by this system in terms of fielding. It should be noted that a lot of Tulowitzki's value has come from his brilliant performance in"clutch" situations- FanGraphs has his BRAA as 13.86, but his raw WPA is 2.85- his performance in "Clutch" situations has caused his WPA to be 1.43 higher than would be expected.
It's also a fair point that I should have included runs in the comparison between Rollins and Wright, since there was a column for RBIs. This was an honest mistake (rather than trying to make Wright look better)- I was taking the numbers from B-R, and just started with doubles and moved down the line. I didn't notice that runs wasn't there, as it's not really something I take into consideration when comparing players (neither is RBI).
Wright has scored 110 runs, Rollins has scored 135. This is somewhat amazing, as Wrights OBP is 68 points higher. Part of the reason for the large discrepancy is Rollins has had an amazing 761 PAs, compared to Wright's 693. But a bigger factor is the guys who hit behind Rollins. Utley, Burrell, Howard, and Rowand have combined for an amazing 267 extra base hits. Which is exactly the problem with runs- if you put Wright at the top of the Phillies' lineup, he probably would have scored just as many.
Update 2: I didn't incorporate BP's fielding stats into my fielding numbers, which was silly. If I do, Russ Martin jumps to fourth in the NL. The AL top five stays in the same order.