Tom Flesher » Angels

June 15 Wins Above Expectation

tomflesher — Wed, 16 Jun 2010 22:17:17 +0000

Wins Above Expectation are a statistic determined using team wins and the Pythagorean expectation, which is in turn determined using runs scored by and against each team. The Pythagorean expectation is the proportion of runs scored squared to runs scored squared plus runs against squared. It’s interpreted as an expected winning percentage.

Wins Above Expectation (WAE) is then the difference between Wins and Expected Wins, which are simply the Pythagorean Expectation multiplied by Games played. It’s a useful measure because it can be interpreted as wins that are due to efficiency (in economic terms) or, more simply, play that’s some combination of smart, clutch, and non-wasteful. It rewards winning close games and penalizes teams that win lots of laughers but lose close games, since the big wins predict more games will be won when all those runs are spent winning only one game.

Using Baseball-Reference.com, I crunched the numbers for AL teams up to June 15. As usual, the Los Angeles Angels of Anaheim lead the league in WAE with 3.68, with Detroit’s 2.39 a close second, but the Tampa Bay Rays are a surprising last with -1.96 WAE. Obviously, this early in the season it’s too soon to conclude anything based on this, but the complete data is behind the cut.

Team	RS	RA	W	pythwin	WAE
BAL	211	342	18	17.92	0.08
BOS	359	308	38	38.02	-0.02
CHW	273	300	29	28.54	0.46
CLE	268	318	25	26.16	-1.16
DET	278	277	34	31.61	2.39
KCR	300	334	28	29.02	-1.02
LAA	316	332	36	32.32	3.68
MIN	304	248	37	38.43	-1.43
NYY	363	255	41	42.85	-1.85
OAK	270	283	33	31.45	1.55
SEA	226	300	24	23.53	0.47
TBR	343	240	41	42.96	-1.96
TEX	324	284	36	36.19	-0.19
TOR	313	294	35	35.06	-0.06

Three Catchers, Four Starters, and Other Playoff Thoughts

tomflesher — Mon, 26 Oct 2009 15:53:54 +0000

Last night, the LA Angels lost Game 6 of the 2009 ALCS to the New York Yankees. Mike Scioscia started left-handed pitcher Joe Saunders; he carries, as is becoming the norm, three catchers including light-hitting third catcher Bobby Wilson. Joe Girardi also carries three catchers, although his array includes defensive specialist Jose Molina, sometime-DH Jorge Posada, and Francisco Cervelli, who hit .298 in 94 at-bats this season. Though Mike Napoli was hot during the postseason, Scioscia’s group of catchers wasn’t as specialized as it was in 2005, when he carried big-hitter Bengie Molina, Jose Molina for his glove, and Josh Paul for emergencies. Here, he appeared to be carrying three catchers solely because none of them are big hitters. In retrospect, although Napoli and Mathis are both a big part of the Angels clubhouse, Scioscia should have made a move during the regular season to replace one of them with a catcher who was more of the Bengie Molina or Jorge Posada mold – someone whose glove or arm is slightly defective, but who can hit the ball when necessary. Instead, Scioscia was forced to burn two pinch hitters and a second catcher in his attempt to win the game last night, whereas Girardi has in previous games been able to use the traditional approach of starting Molina and using Posada to pinch hit, or starting Posada and using Molina as a defensive replacement late in the game. In a perfect world, Scoscia could have traded Kendry Morales away and acquired Victor Martinez to use mainly at first base and as an emergency third catcher, replacing Wilson’s more or less dead weight with a big bat but not forgoing any real utility.

In addition, Scioscia started Joe Saunders. This isn’t a crime in and of itself. However, in the ALCS, he started John Lackey, Saunders, Jered Weaver, and Scott Kazmir. Girardi, meanwhile, is using Joe Torre’s time-honored trick of carrying only three starters (CC Sabathia, Andy Pettitte, and AJ Burnett) and using traditional long-relief men like Dan Robertson in addition to standard situational relief like Joba Chamberlain, Damaso Marte, and Mariano Rivera. In Game 6, Saunders went only 3.1 innings. Weaver performed well in relief and, frankly, should have been left there for the duration of the series. Instead, Scioscia spread his men too thin and was left making an all-hands-on-deck call in the late games where he used both Weaver and Kazmir in relief. Saunders pitched brilliantly in Game 2, and Scioscia should have been prepared to maximize his usage of Lackey, Saunders, and Kazmir while leaving Weaver in the bullpen. Granted, Saunders pitched like crap last night, but all pitchers have their off nights.

Finally, Girardi will probably do quite well in the World Series, as he’s experienced in managing under National League rules. Hideki Matsui, with his legs in bad shape, will be almost entirely useless in the Phillies’ park. In a perfect world, Girardi would be able to dump fifth-outfielder Freddy Guzman and use Matsui in the field. However, that seems unlikely, so Matsui will remain an overpaid pinch-hitter. With Jerry Hairston, Jr., on the bench, Guzman’s utility as a pinch runner is moderate at best. It would be a gutsy move, but I think Girardi would do best to dump Guzman and bring Shelley Duncan in as a pinch hitter and emergency outfielder.

Still, Girardi gets paid the big bucks to do his job, so I’m sure every move he makes is well-considered.

Wins Above Expectation (with a side of run differential)

tomflesher — Tue, 02 Sep 2008 01:02:45 +0000

In continuing my thoughts about the Pythagorean Expectation from about a week ago, I took a look at the MLB standings for the period ending August 31, 2008. I played with the stats a little bit, since I haven’t really thought through the basis for most of them.

Today’s project: find Pythagorean expectations for each team, then find the difference between the actual and expected win percentages (“pythagorean difference”). Apply the pythagorean difference to the total number of games played to determine a team’s Wins Above Expectation by multiplying the total number of games by the pythagorean difference.

Practical application: none.

Discussion and numbers behind the cut.

I’m using OpenOffice.org Calc and numbers that I copypasted from ESPN.com, cited above. The formatting is a little wonky because this was just a play session for me, but here are my data in handy dandy PDF format (original spreadsheet format available upon request).

Wins Above Expectation is a measure of the economy of a particular baseball team – the ability to win more games than the number of runs scored would predict. I would therefore hypothesize it to be useful as a measure of defensive ability, though of limited use from a predictive standpoint because anything it would predict could be more elegantly but less surely predicted using other measures.

Speaking of elegance, I can’t help but notice that the pythagorean expected rank and the rank by run differential are the same in all cases. The elegance of run differential as a method of ranking teams’ performance hadn’t occurred to me before, but I’ll probably continue to use it. The use of pythagorean expectation is to predict a number of wins given a particular number of games. (The correlation between expected rank and rank by run differential is obvious after thinking it through, since pythagorean expectation is basically just a special case of differential.)

The Rays’ exceedingly economical performance isn’t surprising, since they’ve been squeaking out wins regularly all season. As a team, they rank second in MLB in the teams’ number of saves (a stand-in variable for close wins), behind only the LA Angels (who beat them in terms of WAE as well). There’s also no surprise that one of this season’s biggest punching bags, Toronto, is last in the league in negative WAE (that is, wins below expectation). This is what happens when you lose tight games and get your wins by enormous margins. Lesson to be learned: consistent performance creates measuring statistics that closely match performance.

Edit to Add: I added an additional page of stats using the 1.81 exponent cited in the Wikipedia article. The numbers changed; the ranks didn’t.