Baseball for the Thinking Fan

Login | Register | Feedback

btf_logo
You are here > Home > Baseball Newsstand > Baseball Primer Newsblog > Discussion
Baseball Primer Newsblog
— The Best News Links from the Baseball Newsstand

Thursday, October 25, 2012

Should we ever use a complex ERA estimator?

KISS.

There’s a chance that the more complex estimators work better for special circumstances, like pitchers who change teams, throw a ton of groundballs, or are remarkably adept at keeping the ball in the yard. Also, they could add descriptive value over simply using the combination of FIP and batting average on balls in play, but I have yet to hear a really great argument explaining that fact.

What I can tell you though is that when a predictor is made more complex, it must add more predictive value, by a significant amount. If it does not, then my only response can be just two words:

Occam’s Razor.

Jim Furtado Posted: October 25, 2012 at 09:51 AM | 10 comment(s) Login to Bookmark
  Tags: sabermetrics

Reader Comments and Retorts

Go to end of page

Statements posted here are those of our readers and do not represent the BaseballThinkFactory. Names are provided by the poster and are not verified. We ask that posters follow our submission policy. Please report any inappropriate comments.

   1. Drew (Primakov, Gungho Iguanas) Posted: October 25, 2012 at 09:58 AM (#4282854)
Why isn't the response, "Scrap it"?
   2. Mike Emeigh Posted: October 25, 2012 at 10:41 AM (#4282896)
What I can tell you though is that when a predictor is made more complex, it must add more predictive value, by a significant amount. If it does not, then my only response can be just two words:

Occam’s Razor.


Or maybe it's an indication that the underlying behavior is more complex that your simple model of the relationship.

-- MWE

   3. snapper (history's 42nd greatest monster) Posted: October 25, 2012 at 10:44 AM (#4282902)
What I can tell you though is that when a predictor is made more complex, it must add more predictive value, by a significant amount. If it does not, then my only response can be just two words:

Occam’s Razor.


I don't necessarily agree with this. All these FIP/xFIP etc are already way past the point that the avg. fans (even stat inclined) can calculate them himself. With modern computing power, who cares how complex it is?

If a full projection system like ZiPs/Oliver/Cairo is necessary to get the best estimate, why do I care if it's complex?
   4. DJS From Suplex City! Posted: October 25, 2012 at 11:03 AM (#4282917)

If a full projection system like ZiPs/Oliver/Cairo is necessary to get the best estimate, why do I care if it's complex?


Yeah, it's not like I make you guys run ZiPS! Whether you like or don't like the projections, for the end-user, the only complexity is looking at a website.
   5. snapper (history's 42nd greatest monster) Posted: October 25, 2012 at 11:36 AM (#4282942)

Yeah, it's not like I make you guys run ZiPS! Whether you like or don't like the projections, for the end-user, the only complexity is looking at a website.


Question, Dan. Is ZiPs a full blown regression/forecasting model?
   6. cardsfanboy Posted: October 25, 2012 at 12:49 PM (#4283007)
What I can tell you though is that when a predictor is made more complex, it must add more predictive value, by a significant amount. If it does not, then my only response can be just two words:


Is Fip better than component era by a significant amount? I thought it was barely noticeable difference.
   7. TomH Posted: October 25, 2012 at 01:54 PM (#4283102)
Tom's postulate:
differences in pitching projections are not primarily driven by differences in ERA estimator systems
differences in pitching projections are primarily driven by differences in change-over-time, park-and-defense effect adjustments, and possibly minor-league weighting of estimator systems

(edited)
   8. Tricky Dick Posted: October 25, 2012 at 02:19 PM (#4283117)
I like having all of the estimators available. I think the mistake is to fall in love with one particular estimator as the be all, end all method. My philosophy: look at all of the results and use your judgement in how to weight them. If one method produces an outlier result for a pitcher, think about why that may be the case, and either reject the outlier or use the outlier to temper your view of the other methods (depending on the circumstances).

Generally, FIP and x-FIP are pretty good (and produce similar results to SIERA or tERA), but I think there are occasions when factors like groundball tendency are important, and the more complex estimator may provide additional useful information.
   9. birdlives is one crazy ninja Posted: October 25, 2012 at 07:02 PM (#4283432)
Question, Dan. Is ZiPs a full blown regression/forecasting model?

I've heard Dan say that ZiPs relies on Monto Carlo simulations, which I believe doesn't rely upon any linear or non-linear regression models.
   10. snapper (history's 42nd greatest monster) Posted: October 25, 2012 at 09:35 PM (#4283667)
I've heard Dan say that ZiPs relies on Monto Carlo simulations, which I believe doesn't rely upon any linear or non-linear regression models.

How does he get the means and distributions for the simulations? i.e. how do you translate past stats into future probabilities w/o regression?

You must be Registered and Logged In to post comments.

 

 

<< Back to main

BBTF Partner

Support BBTF

donate

Thanks to
1k5v3L
for his generous support.

Bookmarks

You must be logged in to view your Bookmarks.

Hot Topics

NewsblogMariners fire general manager Jack Zduriencik
(50 - 10:42am, Aug 29)
Last: Dag Nabbit at ExactlyAsOld.com

NewsblogOT: Soccer August 2015
(495 - 10:40am, Aug 29)
Last: Shooty Is Disappointed With His Midstream Urine

NewsblogOTP - August 2015: Meet the … Baseball Owner Funding the 2016 Campaign ...
(4640 - 10:00am, Aug 29)
Last: Howie Menckel

NewsblogPrimer Dugout (and link of the day) 8-28-2015
(18 - 9:57am, Aug 29)
Last: Rennie's Tenet

NewsblogIts OK to have the hots for baseball players: A Manifesto
(32 - 9:30am, Aug 29)
Last: BDC

NewsblogSwihart's inside-the-park homer | MLB.com
(2 - 9:27am, Aug 29)
Last: Jose Is The Most Absurd Thing on the Site

NewsblogDan Shaughnessy: With Don Orsillo news, Red Sox drop the ball again - The Boston Globe
(13 - 9:25am, Aug 29)
Last: Jose Is The Most Absurd Thing on the Site

NewsblogEach season has an autopsy. Here’s an early version for the Nationals. - The Washington Post
(20 - 9:19am, Aug 29)
Last: ERROR---Jolly Old St. Nick

NewsblogSB Nation: Pirates outfielder may have made the most chill out in MLB history
(58 - 9:16am, Aug 29)
Last: A big pile of nonsense (gef the talking mongoose)

NewsblogJON HEYMAN: MLB prevails over Barry Bonds in collusion case over his career ending
(45 - 9:13am, Aug 29)
Last: Adam Starblind

NewsblogOMNICHATTER 8-29-15
(2 - 8:41am, Aug 29)
Last: bunyon

NewsblogInside Baseball: Keys to Cubs' success, plus more MLB news and notes - CBSSports.com
(10 - 5:44am, Aug 29)
Last: Walt Davis

Newsblog8-28-15 OMNICHATTER
(115 - 1:33am, Aug 29)
Last: Spahn Insane

NewsblogThe Pyramid Rating System: JAWS on a Career Scale – The Hardball Times
(99 - 12:22am, Aug 29)
Last: Jay Z

NewsblogLos Angeles Dodgers can hit and get on base -- so why can't they score? | FOX Sports
(11 - 12:07am, Aug 29)
Last: PASTE Will Notice Harper When He Hits .467 (Zeth)

Page rendered in 0.1987 seconds
44 querie(s) executed