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

Tuesday, November 13, 2012

Camden Depot: Measuring Bullpen Management: Bucking Up the Bullpen

Jon Shepherd suggests a way to evaluate a manager’s bullpen usage over time, drawing on Dan Lependorf’s article at Hardball Times:

A Hardball Times article suggested using WPA - WPA/LI as a measure of bullpen performance that would be useful in assessing bullpen management.  WPA is the acronym for Wins Probability Added.  This is calculated as the difference in win expectancy before and after an event. LI is the Leverage Index.  It is a measurement of how consequential a specific scenario is based on the inning, outs, score, baserunners, and baserunner position.  By using the two statistics in concert, you arguably have a measure that gives you a context neutral wins added metric.

To test whether this metric would give an indication that managers have skill associated with using a bullpen well, I decided to take the last five seasons of several recent managers.  I compare each manager’s mean for WPA, WPA/LI, and WPA-WPA/LI (ANOVA).  WPA will inform us simply if certain teams wind up with better outcomes for winning based on reliever usage.  WPA/LI will neutralize all situations and measure reliever ability in general (similar to wOBA).  WPA-WPA/LI is being used to inform us about whether relievers actually perform better in clutch situations.  If one of these statistics indicate an actual skill then the numbers associated with a manager should be (1) repeatable and (2) result in managers being different from each other.  Of course, this assumes that these things are, in fact, measurable.

The results are somewhat as you might expect: Showalter, Joe Girardi, and Joe Maddon do well, Eric Wedge, Ozzie Guillen and Mike Scioscia do relatively poorly. There are a couple of surprises mixed in - Ron Washington in the upper tier, Bruce Bochy and Jim Leyland near the bottom.

Not a perfect study, but an excellent start.

Mike Emeigh Posted: November 13, 2012 at 10:57 AM | 0 comment(s) Login to Bookmark
  Tags: bullpens, managers, 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.

You must be Registered and Logged In to post comments.

 

 

<< Back to main

BBTF Partner

Support BBTF

donate

Thanks to
Darren
for his generous support.

Bookmarks

You must be logged in to view your Bookmarks.

Hot Topics

NewsblogGossage on Bonds, McGwire Hall hopes: ‘Are you f–king kidding?’
(127 - 10:36pm, Jul 28)
Last: tfbg9

NewsblogBarney + cash to Dodgers for PTBNL
(3 - 10:34pm, Jul 28)
Last: McCoy

NewsblogOMNICHATTER 7-28
(60 - 10:33pm, Jul 28)
Last: Walks Clog Up the Bases

NewsblogPrimer Dugout (and link of the day) 7-28-2014
(48 - 10:19pm, Jul 28)
Last: Eric J can SABER all he wants to

NewsblogFormer OF Jason Lane takes loss in first start
(20 - 10:14pm, Jul 28)
Last: Random Transaction Generator

NewsblogOT: Monthly NBA Thread- July 2014
(998 - 10:03pm, Jul 28)
Last: clowns to the left of me; STEAGLES to the right

Newsblog2014 Prospect Watch | MLB.com: UPDATED
(18 - 10:01pm, Jul 28)
Last: DKDC

NewsblogOTP - July 2014: Republicans Lose To Democrats For Sixth Straight Year In Congressional Baseball Game
(3440 - 9:40pm, Jul 28)
Last: They paved Misirlou, put up a parking lot

NewsblogDmitri Young explains his amazing weight loss
(31 - 9:30pm, Jul 28)
Last: They paved Misirlou, put up a parking lot

NewsblogESPN: Yankee Fan Returns Lost Red Sox World Series Ring
(23 - 9:09pm, Jul 28)
Last: tshipman

NewsblogDodgers and Diamondbacks Triple-A teams involved in wild brawl
(25 - 7:47pm, Jul 28)
Last: Bhaakon

NewsblogOT: The Soccer Thread July, 2014
(461 - 7:45pm, Jul 28)
Last: TFTIO can't talk like this -- he's so sorry.

Hall of MeritMost Meritorious Player: 1957 Discussion
(4 - 7:44pm, Jul 28)
Last: toratoratora

NewsblogHall of Fame Announces Changes to Voting Process for Recently Retired Players, Effective Immediately
(98 - 7:20pm, Jul 28)
Last: Gonfalon Bubble

NewsblogFull Count » Mike Carp explains why he requested a trade from Red Sox
(35 - 7:20pm, Jul 28)
Last: Joe Bivens, Minor Genius

Page rendered in 0.1625 seconds
50 querie(s) executed