Baseball Primer Newsblog
— The Best News Links from the Baseball Newsstand
Sunday, November 04, 2012
Nate Silver, Cosh, Tango, PECOTA, Marcel the Monkey!...It’s almost like the golden days of Primer! Backlasher, RossCW come on down!
The whole world is suddenly talking about election pundit Nate Silver, and as a longtime heckler of Silver I find myself at a bit of a loss. These days, Silver is saying all the right things about statistical methodology and epistemological humility; he has written what looks like a very solid popular book about statistical forecasting; he has copped to being somewhat uncomfortable with his status as an all-seeing political guru, which tends to defuse efforts to make a nickname like “Mr. Overrated” stick; and he has, by challenging a blowhard to a cash bet, also damaged one of my major criticisms of his probabilistic presidential-election forecasts. That last move even earned Silver some prissy, ill-founded criticism from the public editor of the New York Times, which could hardly be better calculated to make me appreciate the man more.
...For most players in most years, Silver’s PECOTA worked pretty well. But the world of baseball research, like the world of political psephology, does have its cranky internet termites. They pointed out that PECOTA seemed to blunder when presented with unique players who lack historical comparators, particularly singles-hitting Japanese weirdo Ichiro Suzuki. More importantly, PECOTA produced reasonable predictions, but they were only marginally better than those generated by extremely simple models anyone could build. The baseball analyst known as “Tom Tango” (a mystery man I once profiled for Maclean’s, if you can call it a profile) created a baseline for projection systems that he named the “Marcels” after the monkey on the TV show Friends—the idea being that you must beat the Marcels, year-in and year-out, to prove you actually know more than a monkey. PECOTA didn’t offer much of an upgrade on the Marcels—sometimes none at all.
PECOTA came under added scrutiny in 2009, when it offered an outrageously high forecast—one that was derided immediately, even as people waited in fear and curiosity to see if it would pan out—for Baltimore Orioles rookie catcher Matt Wieters. Wieters did have a decent first year, but he has not, as PECOTA implied he would, rolled over the American League like the Kwantung Army sweeping Manchuria. By the time of the Wieters Affair, Silver had departed Baseball Prospectus for psephological godhood, ultimately leaving his proprietary model behind in the hands of a friendly skeptic, Colin Wyers, who was hired by BPro. In a series of 2010 posts by Wyers and others called “Reintroducing PECOTA”—though it could reasonably have been entitled “Why We Have To Bulldoze This Pigsty And Rebuild It From Scratch”—one can read between the lines.
for his generous support.
You must be logged in to view your Bookmarks.
: [OTP-May] Politico: Congressional baseball game, May 1, 1926
(3705 - 3:48pm, May 21)Last:
: Sherman: Mets' roster of rubbish makes it impossible to evaluate Collins
(46 - 3:47pm, May 21)
Last: if nature called, ladodger34 would listenNewsblog
: Joe Maddon calls ump's position 'baseball anarchy'
(17 - 3:46pm, May 21)
: JM Catellier: Is Pedro Martinez a First Ballot Hall of Famer?
(92 - 3:46pm, May 21)
: Posnanski: Jeff Francoeur and ANT
(21 - 3:45pm, May 21)
: OT: The Soccer Thread, May 2013
(1038 - 3:45pm, May 21)Last:
Shooty is in the Trust TreeNewsblog
: Slate: The Dreaded C-Word
(13 - 3:41pm, May 21)
: White Sox Ace Chris Sale Eats and Eats and Eats Without Gaining Any Weight
(37 - 3:38pm, May 21)
Last: The Good FaceNewsblog
: Dollar Sign on the Glistening Muscle: Scouting Ballplayers in 1980s Playgirl
(17 - 3:32pm, May 21)
: Yanks, Manchester City awarded MLS expansion team
(15 - 3:29pm, May 21)
Last: Pat Rapper's DelightNewsblog
: OMNICHATTER for MAY 21, 2013
(7 - 3:23pm, May 21)
Last: Rickey Fredonia Fudge Duckery Precious TwiddleNewsblog
: SB Nation: Five lost scouting reports
(5 - 3:13pm, May 21)
Last: Floyd ThursbyNewsblog
: OT: NBA Monthly Thread - May 2013
(1008 - 3:13pm, May 21)Last:
: Barry Bonds: Detroit Tigers' Miguel Cabrera 'the best' ... but not better than me
(46 - 3:10pm, May 21)
Last: snapper (history's 42nd greatest monster)Newsblog
: Washington Post: Tom Boswell: Yankees Are Monuments To Baseball Success
(15 - 3:03pm, May 21)
Last: Slivers of Maranville (SdeB)