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September 1, 2004
Lies, Damned Lies
The Tougher League
Turn on "Baseball Tonight" these days and you're sure to see one of the insightful commentators mention just how loaded the National League is this season. The senior circuit, indeed, has had its share of dominating performances. The top seven players in Value Over Replacement Player are all National Leaguers (yes, Dorothy, the list does include Mark Loretta). Although Johan Santana has surged to the top of the pitching VORP board, 11 of the top 16 performances on that list belong to NLers.
Dominating individual performances, however, do not reflect a dominant league. On the contrary, dominating performances are easier to come by when the league talent pool is thinner; think of the gaudy numbers that NCAA players or preps put up. As baseball's talent base has grown deeper, the number of dominant performances has decreased, with the standard deviation of most critical statistics decreasing over time (see also: Stephen Jay Gould's essay on the disappearance of the .400 hitter). That ALers are having a tougher time tearing their league a new one suggests that it is the better league, and not the worse one.
Can we conjure up some further evidence in support of this contention? Let's take a look at the performances of players who have switched leagues in the past year; hitters who accumulated at least 200 plate appearances in the National League last season and at least 200 PA in the AL thus far this year, as measured by Equivalent Average. By my count, there are 24 such players. By the way, any resemblance to the Davenport Translations is purely intentional--Clay uses a very similar, if more exacting, process to come up with his numbers.
Table 1: NL to AL Crossovers - Hitters
Player Team 2004 EqA 2003 EqA Vladimir Guerrero ANA .328 .326 Jose Guillen ANA .305 .325 Javy Lopez BAL .297 .334 Mark Bellhorn BOS .288 .232 Jose Uribe CWS .264 .232 Timo Perez CWS .215 .237 Ron Belliard CLE .283 .250 Ivan Rodriguez DET .309 .291 Rondell White DET .286 .273 Matt Stairs KCR .266 .312 Gary Sheffield NYY .326 .337 Miguel Cairo NYY .254 .236 Kenny Lofton NYY .268 .278 Mark Kotsay OAK .279 .262 Damian Miller OAK .273 .239 Jolbert Cabrera SEA .259 .269 Rich Aurilia* SEA .231 .260 Tino Martinez TBD .288 .273 Jose Cruz, Jr. TBD .275 .272 Geoff Blum TBD .223 .229 Robert Fick TBD .209 .263 Eric Young TEX .274 .254 Gary Matthews, Jr. TEX .266 .264 Rod Barajas TEX .236 .198 Average .271 .269 * Aurilia's 2003 stats include his 2004 performance since returning to the NL.There is not much evidence that the AL is the superior league. In fact, the hitters have their EqA by a trivial amount on average. While players like Rich Aurilia and Robert Fick have struggled in new surroundings, others like Mark Bellhorn and Juan Uribe have thrived.
How about the opposite side of the coin?
Table 2: AL to NL Crossovers - Hitters
Player Team 2004 EqA 2003 EqA Todd Walker CHC .274 .263 D'Angelo Jimenez CIN .261 .261 Carlos Beltran** HOU .324 .298 Milton Bradley LAD .279 .322 Ben Grieve MIL .269 .267 Tony Batista MON .231 .230 Mike Cameron NYM .284 .279 Shane Spencer NYM .264 .253 Todd Zeile NYM .239 .235 Karim Garcia* NYM .230 .237 Marlon Anderson STL .221 .260 Ramon Hernandez SDP .283 .274 Terrence Long SDP .271 .239 A.J. Pierzynski SFG .265 .285 Dustan Mohr SFG .300 .250 Deivi Cruz SFG .267 .224 Average .266 .261 * Garcia's 2003 stats include his 2004 performance since returning to the NL. ** Beltran's statistics represent his 2004 performances in the NL and AL, respectively.We've thrown Carlos Beltran into the mix, as he has already accumulated 200 PAs in both leagues this season, to go along with a whole boatload of other impressive numbers. As a group, the AL to NL crossovers have improved their performance; to borrow from market-geek terminology, there are twelve advancers against just four decliners, with the average player improving by about five points of EqA.
We can evaluate the performances of pitcher crossovers, too. We will use Normalized Run Average (NRA), one of the many statistics that are updated daily on our revamped and highly underrated DT player cards, as our basis for comparison. Pitchers must have thrown at least 50 innings in each league in order to qualify.
Table 3: NL to AL Crossovers - Pitchers
Player Team 2004 NRA 2003 NRA Curt Schilling BOS 3.08 3.12 Carlos Silva MIN 4.51 6.45 Joe Nathan MIN 1.35 2.38 Javier Vazquez NYY 4.33 3.61 Kevin Brown NYY 4.24 3.24 Paul Quantrill NYY 4.45 2.61 Mark Redman OAK 4.51 3.97 Ron Villone SEA 5.54 4.20 Miguel Batista TOR 4.22 3.94 Justin Speier TOR 3.03 4.47 Average 3.93 3.80Once again, we are limited by a small sample size and a wide degree of variance in the individual performances, but pitchers crossing over to the AL have suffered a small performance decline, with their NRA increasing by an average of 13 points. (Admission: every year there are a few outstanding performances that I manage to overlook in the heavy traffic of the baseball season, sometimes until it's time to run the new round of PECOTA forecasts in the winter. Has Joe Nathan been awesome this year or what?).
By contrast, the AL to NL pitching crossovers have done well as a group:
Table 4: AL to NL Crossovers - Pitchers
Player Team 2004 NRA 2003 NRA Steve Sparks ARI 7.04 7.02 Casey Fossum ARI 5.86 5.07 LaTroy Hawkins CHC 2.56 1.90 Cory Lidle PHI 5.70 5.02 Roger Clemens HOU 3.39 3.94 Andy Pettitte HOU 3.74 4.11 Jeff Weaver LAD 4.02 6.51 Doug Davis MIL 3.82 4.18 David Wells SDP 4.12 4.33 Jeff Suppan STL 4.48 5.35 Average 4.47 4.74Here too, the force of our conclusion is limited by the small sample size, but we're beginning to put a case together that the AL is, in fact, the stronger league. All told, 18 of 26 former AL players have improved their performance upon converting leagues, while the NL expatriates are split just about evenly between advances and declines.
It turns out, though, that there is some much stronger evidence for the AL's superiority that is staring us right in the face. Go back and read the list of crossovers presented in the previous tables.
Got it? As it happens, regardless of how well the players have managed to perform in their new leagues, the quality of NL-to-AL crossovers is much higher than the other way around. Eight players who posted VORPs of 40 or higher in the National League last season--Ivan Rodriguez, Gary Sheffield, Vladimir Guerrero, Jose Guillen, Javy Lopez, Kevin Brown, Javier Vazquez and Curt Schilling--are playing in the AL this year. Just three AL players with VORPs of 40 or higher have moved leagues, and that includes Beltran, who has only had a couple of months in his new digs.
Here are the cumulative 2003 VORPs for all the crossovers listed above:
Table 5: Crossovers - 2003 VORP summary
NL to AL Hitters 570.2 NL to AL Pitchers 332.2 Total 902.4 AL to NL Hitters 303.3 AL to NL Pitchers 119.0 Total 422.3 Difference 480.1It would be hard to overstate the enormity of that difference. The National League has had the short end of the stick in terms of player movement, suffering a net loss of about 480 points of VORP, a figure equivalent to nearly 50 wins. To put it somewhat differently, the average NL team has lost about three or four wins' worth of talent in the last year alone, while the average AL team has gained about the same amount.
That is not to suggest that Albert Pujols, Adrian Beltre, Jason Schmidt and so forth are having anything but outstanding seasons; they are great players one and all. But if they were playing in the AL this season, they might be finding the going at least a little bit tougher.