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
aleskel
for his generous support.

Bookmarks

You must be logged in to view your Bookmarks.

Hot Topics

NewsblogMLB - Royals' Ned Yost keeps managing to win - ESPN
(13 - 3:15am, Oct 26)
Last: Bhaakon

NewsblogPhils' philospophy beginning to evolve | phillies.com
(17 - 3:03am, Oct 26)
Last: steagles

Newsblog2014 WORLD SERIES GAME 4 OMNICHATTER
(872 - 2:55am, Oct 26)
Last: PASTE Thinks This Trout Kid Might Be OK (Zeth)

NewsblogOT:  October 2014 - College Football thread
(482 - 1:31am, Oct 26)
Last: Robert in Manhattan Beach

NewsblogBuster Olney on Twitter: "Sources: Manager Joe Maddon has exercised an opt-out clause in his contract and is leaving the Tampa Bay Rays immediately."
(90 - 1:16am, Oct 26)
Last: DFA

NewsblogOT: Politics, October 2014: Sunshine, Baseball, and Etch A Sketch: How Politicians Use Analogies
(3811 - 12:24am, Oct 26)
Last: Howie Menckel

Newsblog2014 WORLD SERIES GAME 3 OMNICHATTER
(521 - 10:56pm, Oct 25)
Last: Sunday silence

NewsblogDave Dombrowski: Injury worse than expected, Miguel Cabrera 'is as tough as you can possibly be' | MLive.com
(30 - 10:52pm, Oct 25)
Last: RMc is a fine piece of cheese

NewsblogOT: Monthly NBA Thread - October 2014
(396 - 8:40pm, Oct 25)
Last: Tom Cervo, backup catcher

NewsblogBoston Red Sox prospect Deven Marrero enjoying turnaround in Arizona Fall League | MiLB.com
(14 - 7:58pm, Oct 25)
Last: Merton Muffley

NewsblogYost's managerial decisions make for extra-entertaining World Series | FOX Sports
(16 - 7:30pm, Oct 25)
Last: BDC

NewsblogGambling Bochy creature of habit when it comes to pitchers | CSN Bay Area
(5 - 6:56pm, Oct 25)
Last: Bug Selig

Hall of MeritMost Meritorious Player: 1959 Ballot
(8 - 6:29pm, Oct 25)
Last: Chris Fluit

NewsblogOT: NBC.news: Valve isn’t making one gaming console, but multiple ‘Steam machines’
(872 - 6:02pm, Oct 25)
Last: Greg K

NewsblogJohn McGrath: The Giants have become the Yankees — obnoxious | The News Tribune
(20 - 4:40pm, Oct 25)
Last: Baldrick

Page rendered in 0.1231 seconds
50 querie(s) executed