The concept of wins above replacement has done wonders for baseball analysis. The logic behind the idea -- that we can measure the effectiveness of players and compare them against those who could theoretically replace them -- has bumped up the IQ of your average baseball fan. But that doesn't mean that the system is without its own set of problems.
There are multiple variations of the WAR concept, and the three that get the most play are Fangraph's WAR (fWAR), Baseball Reference's rWAR, and Baseball Prospectus's WARP. Sometimes none of the three agree about a player's value. For instance, depending on which website you like to sit down to read while you drink your morning coffee, you may have found Boston's Dustin Pedroia as a viable threat to Jose Bautista for American League MVP. The numbers would back you up, too, but a change in URL could invalidate the argument before your coffee has a chance to cool off. Let's approach that same story from the viewpoint of each set of data, and see where it gets us.
Adrian Gonzalez has been getting the attention in the mainstream, but it's teammate Dustin Pedroia who should have Jose Bautista worried. The diminutive second baseman provides more offense per square inch than any hitter in baseball, as his 143 wRC+ attests.
His offense doesn't match Bautista's -- the Blue Jay has a 208 wRC+ that's better than almost anything you can think of outside of Barry Bonds at his peak -- but he makes up for it in the field. Pedroia has already been worth 12.6 runs with the leather according to UZR, compared to Bautista's -1.1 mark. Pedroia doesn't have to keep hitting like he has the last two months to catch Bautista, if he keeps on fielding that well: Pedroia is at 6.2 fWAR at present, and Bautista at 6.8.
While he isn't there just yet, he is close enough that we can start to talk about Pedroia as a viable MVP candidate in 2011. After all, the next cluster of American League WAR leaders are more than a full win behind Bautista and comfortably behind the Red Sox second baseman.
Jose Bautista owns a line that deserves a double-take, but after a slow April and May that had very little power production, Dustin Pedroia is working his way into the MVP conversation here, too. Pedroia sits at .304/.404/.476 with 13 homers -- just four off of his career high despite the slow start and the low run environment of 2011-- and, if he continues the laser show he has displayed the last two months, will finish with the most productive season of his career.
He may have to keep it up if he wants to catch Bautista, though, as the Blue Jays outfielder/third baseman has produced 6.7 rWAR nearly four months into the season, while Pedroia, thanks to his slow start at the plate, is at "just" 5.5 rWAR. That puts him ahead of everyone else in the American League, including teammates Jacoby Ellsbury and Adrian Gonzalez, who are both at 4.9 rWAR.
It will be difficult for Pedroia to close the gap with just two months to go, but if he can avoid another powerless stretch, it's plausible, especially with his defensive edge. Bautista isn't bad, as he has 0.4 defensive WAR, but Pedroia has already earned a full win with his glove, and will be able to sneak in some extra value thanks to his baserunning (Pedroia is 20 for 23 on stolen bases, compared to Bautista's five for eight).
There has been a lot of noise about Adrian Gonzalez as an MVP candidate, and while that has been shot down in many stat-friendly circles, the new challenger that appeared from within their midst was no better a choice. Dustin Pedroia is in the midst of an impressive stretch -- he has a 23-game hit streak in which he has hit .392/.451/.706 with a True Average topping .400 -- but he isn't even within shouting distance of Bautista.
Pedroia's two-month stretch of total dominance has brought him up to 4.6 WARP, a full three wins behind Bautista, who may finish with a higher season WARP even if angels come down from heaven tomorrow and take him back to his rightful home, ending his season. Pedroia is but a speck of cosmic dust in a Bautista-oriented universe, and there just isn't enough season left for Pedroia to catch up.
It's not just offense, either, as Pedroia also lags behind Bautista defensively. The Jays outfielder/third baseman has produced eight runs with the glove compared to Pedroia's five.
Pedroia, like Gonzalez, isn't even the best option from his own team to challenge Bautista -- that honor goes to Jacoby Ellsbury, who is at 5.1 WARP, second in the majors. About the only thing Pedroia and Ellsbury have in common, besides playing for the Red Sox, is that neither of them is playing nearly as well as Bautista.
All three are valid points of view based on the data on the individual websites, and all have a legitimate claim as to being the correct place to go for all your statistical needs. The right answer is that we just don't know: WAR doesn't have the precision we sometimes like to say it does.
Remember that point when you vehemently defend Pedroia as an MVP candidate over the next few months, as someone with a slightly different point of view, but the same underlying ideals, could argue just as strongly against you -- and be just as "correct."