Thursday, August 26, 2004

Poor Sabermetrics

Every once in a while I come across an article that reminds me how important it is to be careful with how we use numbers to evaluate the performances of baseball players. Tom Alexander's new column at Chicago Sports Review is one such article.

Alexander's thesis is that because a walk is as good as a hit, OPS undervalues walks since it gives a player credit for singles in both on-base percentage AND slugging percentage but only credits the player for walks in on-base percentage. "Let’s think about this for a second, though." writes Alexander. "Obviously in most cases a walk is as good as a single."

Alexander does not even attempt to convince us of this, which is strange, since it seems obvious to me that a walk is not as good as a single. A walk can only advance baserunners who are forced to the next base; a single can advance baserunners as far as their legs can carry them. A single can score a man from second; a walk cannot. With the bases empty, a walk is as good as a hit, but with runners on, a single is clearly better. That is why OPS is good at explaining how much a hitter contributes to his team, despite the fact that walks and singles are counted differently.

Alexander continues: "There needs to be a new very basic statistic that is simply (BB+HBP+TB)/(BB+HBP+AB)." (The parentheses, which are pretty clearly needed, were added by me.) Why do we need such a statistic? I'm not saying we don't need it, just that it's still not clear that we do. What explanatory or predictive value would such a statistic have?
Here, finally, Alexander's findings might amount to something, even if I'm not sure what it is. He christens his new statistic "Alexander Rating" or "AR." (Oh boy. I'm going to pretend that's named after Grover Cleveland Alexander.) He then lists the players whose 2004 AR rankings are much higher than their OPS rankings. The list includes Jose Valentin, Mike Cameron, Carlos Delgado, Chipper Jones and other guys who have lots of walks and low batting averages.

Alexander writes, "Ultimately, though, Batting Average, and even OBP is a poor measure [sic] of what they bring to the team, because their real value comes in the idea that when they get a hit, it's a big one." But what about all the outs these guys chew up in the process?

Next there's a list of guys whose OPS rankings are far higher than their AR rankings. The list includes Ichiro, Michael Young, Johnny Estrada, Lyle Overbay and other guys who've gotten a lot of singles this year. Alexander: "I'm not saying that they're not having great seasons, but in certain cases, OPS is a bad measure of how good of an offensive player someone is, particularly when juxtaposed with AR."

Alexander doesn't give any actual reasons for this, but in a certain sense he may be right. AR has, as far as I can see, zero explanatory value - walks simply aren't as good as singles. But it may have some predictive value, in that I'd bet a lot of guys on the second list - the ones whose value is heavily concentrated in singles - are going to take steps backward next year. Singles are much more likely to fluctuate greatly from year to year than walks or power.

Still, the premise upon which Alexander's study is based - that a walk is really as good as a hit - is the sort of counterintuitive and wrong kind of thinking that makes non-sabermetric types of fans throw their hands up and think it's all snake oil.

Thanks to Baseball Primer for the link.


Blogger Rowdy said...

It cracks me up when writers name new statistics after themselves.

5:27 PM  
Blogger Charlie said...

To his credit, after I posted this, Alexander did come on Primer and claim that he was just kidding about the name. But yeah, it's pretty much the height of arrogance.

12:52 PM  
Blogger ninest123 said...

louboutin shoes, nike free, sac longchamp, louis vuitton, christian louboutin outlet, louis vuitton, jordan shoes, polo ralph lauren outlet, replica watches, prada handbags, ray ban sunglasses, nike outlet, longchamp outlet, oakley sunglasses, longchamp, ray ban sunglasses, louis vuitton outlet, louis vuitton outlet, ugg boots, cheap oakley sunglasses, kate spade outlet, oakley sunglasses, tory burch outlet, uggs on sale, ugg boots, replica watches, oakley sunglasses, longchamp outlet, nike free, louboutin pas cher, tiffany and co, prada outlet, nike roshe run, michael kors, longchamp pas cher, louboutin outlet, gucci outlet, ralph lauren pas cher, air max, tiffany jewelry, polo ralph lauren outlet, ray ban sunglasses, nike air max, chanel handbags, nike air max, air jordan pas cher, louboutin, oakley sunglasses, burberry, louis vuitton

9:30 PM  
Blogger ninest123 said...

ralph lauren uk, timberland, true religion jeans, hollister pas cher, north face, michael kors outlet, true religion jeans, north face, new balance pas cher, converse pas cher, nike air max, air force, true religion jeans, replica handbags, mulberry, ray ban uk, hermes, hollister, tn pas cher, michael kors outlet, hogan, michael kors outlet, vanessa bruno, true religion outlet, lacoste pas cher, nike roshe, coach purses, nike blazer, abercrombie and fitch, ray ban pas cher, michael kors, kate spade handbags, coach outlet, vans pas cher, oakley pas cher, sac guess, michael kors, coach outlet, nike air max, ugg boots, nike free run uk, burberry outlet online, michael kors, michael kors outlet, nike air max, burberry, lululemon, michael kors, michael kors outlet, ugg boots

9:30 PM  
Blogger ninest123 said...

hollister, timberland boots, longchamp, instyler, vans shoes, converse, lululemon, mcm handbags, birkin bag, chi flat iron, mac cosmetics, reebok shoes, converse outlet, ghd, baseball bats, iphone cases, lancel, valentino shoes, abercrombie and fitch, vans, nfl jerseys, beats by dre, herve leger, new balance, babyliss, p90x workout, soccer shoes, celine handbags, mont blanc, wedding dresses, north face outlet, louboutin, hollister, nike trainers, hollister, nike huarache, bottega veneta, soccer jerseys, asics running shoes, nike roshe, oakley, nike air max, ferragamo shoes, jimmy choo shoes, ray ban, insanity workout, ralph lauren, north face outlet, gucci, nike air max

9:31 PM  
Blogger ninest123 said...

ugg,ugg australia,ugg italia, wedding dresses, canada goose, pandora charms, louis vuitton, supra shoes, moncler, moncler, canada goose outlet, canada goose outlet, louis vuitton, moncler, pandora jewelry, moncler, moncler, moncler, swarovski, toms shoes, moncler outlet, louis vuitton, ugg,uggs,uggs canada, canada goose, swarovski crystal, bottes ugg, coach outlet, louis vuitton, marc jacobs, moncler, links of london, ugg boots uk, hollister, juicy couture outlet, canada goose, sac louis vuitton pas cher, juicy couture outlet, pandora charms, replica watches, thomas sabo, canada goose, ugg pas cher, karen millen, pandora jewelry, montre pas cher, canada goose uk, doudoune canada goose

9:39 PM  

Post a Comment

<< Home

FREE hit counter and Internet traffic statistics from
Listed on Blogwise Weblog Commenting and Trackback by