Friday, November 30, 2007

John Maine and Oliver Perez: a long day’s journey into VORP

On Baseball Prospectus, if you go to the Team Audits, you can find hitters listed by VORP. VORP is a stat that is used to try and figure out how much a player contributed to in relation to a fictitious “replacement player,” and the stat tells you how many more runs the team scored because a particular player, and not a typical minor-league call up, was at that position. David Wright lead the Mets with 81.1 runs more than a hypothetical minor-league third baseman, followed by Carlos Beltran who was responsible for 51.1 more runs than a hypothetical center fielder; unfortunately for the Mets, the hypothetical minor-league center fielder was unavailable, and they had to call up Carlos Gomez, who was last on the team with a VORP of -4.4.

The stat can be calculated to figure out the effectiveness of pitchers as pitchers—which is useful. In the following discussion I am considering the offense of pitchers, and so my comments have to be taken less as referring to what the stat says about the players and more as what the players say about the stat. Of the Mets hitters John Maine ranked an even zero, which is to say that the average minor league pitcher should have provided exactly as much offense as John Maine: not a shock since it is widely acknowledged that John Maine is a bad hitter even as pitchers go. Tom Glavine (5.2), Jorge Sosa (2.5), El Duque (.8) and Brian Lawrence (.8) all provided slightly more offense than the potential minor-league replacement. Oliver Perez had the worst VORP as a hitter of any Mets pitcher with -1.4, which I found interesting, because, while Perez’ swing is ugly, he does occasionally get his hits and the announcers talk benignly about his efforts at the plate, even going so far as alluding to using him as a pinch-hitter in extreme situations. Perez, indeed, particularly seems like a good hitter compared to Maine, who is, as I mentioned, known as a particularly bad hitting pitcher.

The table on baseball prospectus also lists the player’s batting average, on base percentage, and slugging percentage (total bases over at bats, used to get an idea of a hitter’s power). For Perez, all of these numbers are .161, which means he did not hit a lot, never walked, and only hit singles. Maine’s numbers are .109/.194/.164, which means that while he hit less frequently than Perez, he walked occasionally, and hit for a little bit of power; specifically, he walked five times and hit one homer.

Maine had a total of 6 hits, to Perez’ 9, but broke exactly even with the hypothetical minor leaguer—compared to whom Perez cost the Mets 1.4 runs (a hypothetical minor league pitcher, of course, would have allowed way more runs, 24 to be exact, than Ollie did, so the 1.4 runs that he didn’t hit don’t really matter). In the end this is just another illustration of the general point that on-base and slugging are, according to the new metrics, the major ways in which hitters can help an offense, as opposed to hitting for average. It also, I guess, makes a point about the particular ways in which hitters get to be overvalued based on average. A casual fan would have had a 30 percent better chance of seeing Oliver Perez get a hit of any sort than John Maine; indeed, if they had seen Maine’s lone homer, they probably would have developed an even worse opinion of him, since the event was so wildly celebrated in a way that made a point about its extreme unusualness. Of course, the fans were right to celebrate it: it was good for the fifty-odd points of slugging percentage that propelled Maine’s VORP to zero.

1 comment:

Bambi said...

You write very well.