why does a team outperform its run differential?

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Why Does a Team Outperform its Run Differential? Greg Ackerman Syracuse University Sabermetrics Club

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Why Does a Team Outperform its Run

Differential?Greg Ackerman

Syracuse University Sabermetrics Club

SU Sabermetrics Club

• SABR Student Group Affiliate• Justin Mattingly• Joey Weinberg• Colby Conetta• Ray Garzia• Mallory Miller• Zack Potter• Marcus Shelmidine• Brandon Love• Matt Tanenbaum• Bryan Kilmeade• Justin Moritz• Stephen Marciello• Kyle O’Connor• Willie Kniesner

• Michael Rotondo• Matt Russo• Sam Fortier• Matt Filippi• Isaac Nelson• Zack Albright• John Van Ermen• Colton Smith• Chris Karasinski• Zach Tornabene

Basic Premise

• Explain the Difference between Actual Win Percentage and Expected Win Percentage based on Run Differential (Expected Win Percentage based upon Pythagenpat formula from run differential) • X = ((runs scored + runs against)/games)^.285

• If achieve run differential to possibly put team in playoffs – do not want to squander it• If borderline run differential for playoffs – could be difference in attaining playoff spot

• Will focus on 3 key factors that may influence teams outperforming or underperforming their run differential• Performance of Bench• Relief Pitching• Pitching Depth

• Part II – Add managerial decisions to the model• Pinch Hitters Used• Defensive Substitutions• Relievers Used• Etc.

Rodney Paul
Discuss the premise here - playoff berths are big - once in gives a team a chance at the World Series - if earn run differential to get in - but miss out - missed a big opportunity - our research may help to explain that

Charts

• Average of (Actual Win % - Expected Win %)• Standard Deviation of (Actual Win % - Expected Win %)

• Variables calculated from www.baseball-reference.com

• Team Examples of Difference in Actual Win % - Expected Win %• San Francisco Giants• St. Louis Cardinals• New York Yankees• Toronto Blue Jays• Colorado Rockies

Rodney Paul
This slide sets the stage for some charts - averages, standard deviation - and some team charts over time

Anaheim

Arizona

Atlanta

Baltimore

Boston

Chicago

ChicagoNL

Cincinnati

Cleveland

Colorado

Detroit

Florida

Houston

Kansas C

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ngeles

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Minnesota

New York

New YorkNL

Oakland

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Pittsb

urgh

San Diego

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Seattle

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TampaTexa

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Toronto

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-0.02

-0.015

-0.01

-0.005

0

0.005

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0.015

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0.025

Average of Actual Win% - Expected Win% - By Team - 2000-2013

Rodney Paul
Note the high (i.e NYY, SF) and low (i.e. TOR, COL) teams - this is an average over the 14 seasons

Anaheim

Arizona

Atlanta

Baltimore

Boston

Chicago

ChicagoNL

Cincinnati

Cleveland

Colorado

Detroit

Florida

Houston

Kansas C

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Los A

ngeles

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Minnesota

New York

New YorkNL

Oakland

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Pittsb

urgh

San Diego

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ington0

0.005

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Standard Deviation of Actual Win% - Exp. Win% - By Team – 2000-2013

Rodney Paul
Note some high and low teams here - this is stdev over 14 years - i.e. SF has been pretty consistent here - low standard deviation

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

-0.02

-0.01

0

0.01

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San Francisco Giants - Difference in Actual and Expected Win Percentage

Rodney Paul
Well above 0 - trend line - have outperformed

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

-0.04

-0.03

-0.02

-0.01

0

0.01

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St. Louis Cardinals - Difference in Actual and Expected Win Percentage

Rodney Paul
outperformed

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

-0.04

-0.02

0

0.02

0.04

0.06

0.08

New York Yankees - Difference in Actual and Expected Win Percentage

Rodney Paul
outperformed

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

-0.08

-0.06

-0.04

-0.02

0

0.02

0.04

0.06

Toronto Blue Jays – Difference in Actual and Expected Win Percentage

Rodney Paul
underperformed

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

-0.06

-0.05

-0.04

-0.03

-0.02

-0.01

0

0.01

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Colorado Rockies - Difference in Actual and Expected Win Percentage

Rodney Paul
underperformed

Measures of Bench (Hitters) Performance• OPS+ - On-Base Average plus Slugging Percentage – Adjusted for Park and League• HR – Home Runs• SB – Stolen Bases• CS – Caught Stealing

• Calculated from Baseball Reference – using only bench players listed for each team – weighted average based upon plate appearances of each player

• Ultimately, only included OPS+• Other variables did not add statistical value to the regression model beyond OPS+

Rodney Paul
These are measures club agreed upon to measure bench performance - data from baseball reference

Measure of Relief/Depth Pitcher Performance• FIP – Fielding Independent Pitching• ERA+ - Earned Run Average adjusted for ballpark• SO/W – strike out to walk ratio

• Calculated as a weighted average based upon innings pitched• Calculated for group of “relievers” noted on Baseball-Reference – includes

closer and top 4 used relievers• Calculated for group of “depth” pitchers noted on Baseball Reference-

includes pitchers not included in “starters” or “relievers” categories

Rodney Paul
Measures of relief/depth pitching - we split into groups - Baseball Reference has starters listed in a group, then relievers, then rest (depth)

Regression Model I

• After different regression model incarnations – settled upon the following to illustrate results:

• (Actual – Expected Win %)i = α0 +β1 (Bench OPS+) + β2 (Relief variable) + β3 (Pitching Depth variable) + εi

Regression Results – (Actual Win% - Pyth Win%) on Bench and Relief Pitching Performance

I II III

Intercept 0.0206(1.4307) Intercept 0.0071

(0.5750) Intercept -0.0102(-1.0729)

OPS+ - Bench 0.00001(0.1104) OPS+ - Bench 0.00002

(0.1911) OPS+ - Bench 0.00002(0.1795)

FIP – Relief -0.0044**(-1.9130) ERA – Relief -0.0026

(-1.5358) KBB – Relief 0.0014(1.3735)

FIP – Depth -0.0009(-0.4956) ERA – Depth 0.0001

(0.0756) KBB – Depth 0.0007(0.7328)

Rodney Paul
OLS regression with Actual win % - Exp Win % as dependent variable
Rodney Paul
3 ways to account for pitching - only significant result with FIP - Relief
Rodney Paul
Negative and statistically significant at the 5% level
Rodney Paul
Results correct for Heteroskedasticity and Autocorrelation using Newey-West Errors

Results

• Variables have expected signs for bench (hitter) performance, relief pitching, and pitching depth• Only statistically significant result is for relief pitching performance• Specifically – FIP

• FIP has a negative and significant impact on (Actual Win Percentage – Exp. Win Percentage)• As FIP increases – has negative impact on dependent variable

• More likely to underperform run differential• As FIP decreases – has positive impact on dependent variable

• More likely to outperform run differential

Sample Bench OPS+ Relief FIP Depth FIP

top 10% Seasons - Outperform Run Diff

81.56304 3.66215 4.691264

Bottom 10% Seasons - Underperform Run Diff

81.63799 3.981814 4.769715

% Differential Between Samples

-0.09% -8.03% -1.64%

Rodney Paul
Example to illustrate - top 10% of best seasons in terms of run differential compared to bottom 10% seasons - 8% difference in FIP between best teams and worst teams in terms of over (under) performing run differential

Anaheim

Arizona

Atlanta

Baltimore

Boston

Chicago

ChicagoNL

Cincinnati

Cleveland

Colorado

Detroit

Florida

Houston

Kansas C

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ngeles

Milwauke

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Minnesota

New York

New YorkNL

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Average of Bench OPS+

Rodney Paul
Bench OPS+ for all teams - average over 14 year sample

Anaheim

Arizona

Atlanta

Baltimore

Boston

Chicago

ChicagoNL

Cincinnati

Cleveland

Colorado

Detroit

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FIP - Relief and Pitching Depth

FIP-Relief FIP-Depth

Rodney Paul
FIP - by team - average over 14 year sample

Managerial Decisions

• For Next Step: Added Managerial Decisions to the Data Set

• To measure managerial decisions – used the Bill James Handbook

• Attempt to measure the impact of various managerial decisions on the ability to outperform (underperform) a team’s run differential

Rodney Paul
Transition into adding more data to help tell the story
Rodney Paul
We decided to add managerial information from the Bill James Handbook
Rodney Paul
Believe there is the possibility that managers may contribute to a team over(under) performing its run differential

Managerial Decision Variables

• Pinch Hitters Used• Pinch Runners Used• Defensive Substitutions• Relief Pitchers: Innings Pitched• Stolen Bases Attempted• Sacrifices Attempted• Pitch Outs Ordered

Rodney Paul
list of variables we chose

Regression Model II

• (Actual – Expected Win %)i = α0 +β1 (Bench OPS+) + β2 (Relief FIP) + β3 (Pitching Depth FIP) + β4 (Pinch Hitters) + β5 (Pinch Runners) + β6 (Defensive Substitutions) + β7 (Relief Innings) + β8 (SB Attempts) + β9 (SAC Attempts) + β10 (Pitch Outs) + εi

Variable Coefficient Variable Coefficient

Intercept 0.0200(0.9657)

Defensive Substitutions

0.0003***(3.5602)

OPS+ - Bench -0.00003(-0.2786)

Relief Innings Pitched -0.00004(-1.4258)

FIP – Relief -0.0023(-0.9656)

Stolen Bases Attempted

0.000007(0.3458)

FIP – Depth 0.0012(0.5889)

Sacrifices Attempted -0.00002(-0.2871)

Pinch Hitters Used -0.000004(-0.1621)

Pitch Outs Ordered -0.0002**(-2.0751)

Pinch Runners Used 0.00004(0.4072)

Rodney Paul
Regression Results - adding managerial data to model
Rodney Paul
Def Sub - positive and significant at 1% level
Rodney Paul
Pitch Outs Ordered - negative and significant at the 5% level

Results

• Two statistically significant managerial variables:• Defensive Substitutions – (+) – significant at the 1% level• Pitchouts Ordered – (-) – significant at the 5% level

• Defensive Substitutions – more defensive substitutions used – greater likelihood to outperform run differential• Part is managerial decision• Part is roster flexibility

• Pitchouts Ordered – more pitchouts ordered – greater likelihood to underperform run differential• Part is wasting a pitch• Part is lack of faith in catcher/pitcher• Likely a proxy for risk averse behavior on part of manager

Results

• Relief Pitcher Innings Pitched – (-) but not quite statistically significant (15% level)

• When Managerial Statistics included – impact of FIP-Relievers is lessened as well – no longer statistically significant

• Tried including one or the other – not quite statistically significant

• Appears to still have some marginal effect on ability to outperform/underperform run differential

Sample Defensive Substitutions

Relievers Used

Pitch Outs

top 10% Seasons - Outperform Run Diff

36.0732 444.0732 17.2927

Bottom 10% Seasons - Underperform Run Diff

26.1892 458.7222 21.5000

% Differential Between Samples

37.74% -0.03% 19.57%

Rodney Paul
another example to give context - top/bottom 10% seasons in terms of out/under performing run differential - big differences in Defensive Substitutions

Anaheim

Arizona

Atlanta

Baltimore

Boston

Chicago

ChicagoNL

Cincinnati

Cleveland

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Detroit

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Average of Defensive Substitutions Used

Rodney Paul
Def Sub. by team - average over sample

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Average of Pitchouts Ordered

Rodney Paul
PO ordered - by team - average over sample

Conclusions

• Aimed to determine why teams outperform/underperform run differential• Is it just luck? – or are there factors that contribute to its explanation?• Without Manager Data – it appears that Relief Pitcher Performance (measured by

FIP) plays an important role• Increase in FIP by Relievers – more likely to underperform• Decrease in FIP by Relievers – more likely to outperform

• With Manager Data• Defensive Substitutions – more defensive subs – more likely to outperform• Pitchouts – likely proxy for risk aversion (poor catching performance?) – more pitchouts –

more likely to underperform run differential

• Starting point of our research – hope to learn more in future – open to different variables/approaches to help determine answers

Rodney Paul
Explain the findings again - note that this is our starting point - are open to ideas and hope to continue the research into the future