Which Players Participated in Highest Percentage of Teams' Runs in 2015?

NL MVP Bryce Harper participated in more than a third of  Washington's runs in 2015.
(Photo credit: Patrick Smith, Getty Images)

In previous posts, I presented the Runs Assisted (RAS) statistic and updated an old one (Runs Participated In or RPI).  A player gets credit for a Run Assisted in the following instances: 

• A batter advances a runner to either second or third with a hit, base on balls, hit batsmen, error, sacrifice bunt, or another kind of out.  If that runner then scores either during the same at bat or an ensuing at bat, the batter who advanced him is given a Run Assisted.

• A batter reaches base and is removed for a pinch runner or is replaced by another runner on a force out.  If the new runner then scores, the batter who originally reached base is given a Run Assisted.

A Run Assisted is similar to an assist in hockey because a player doesn't actually score the run/goal, but helps to make it happen.  You could also say that the RBI is like the first assist in hockey and the Run Assisted is like the second assist.  Either way, I think the hockey analogy is apt.

A player gets credit for a Run Participated In if he either scores a run, drives in a run or assists a run, but he can't get double credit for any one run.  The formula is RPI = R + RBI + RAS - HR.  The limitations of these measures were discussed in detail in the above linked posts.

Runs Participated In is a counting statistic which is influenced by opportunity, so it's good to also have a rate measure.  One possibility is Runs Participated In Percentage (RPI%) which is the percentage of a teams' runs in which a player participated.  For example, Tigers second baseman Ian Kinsler participated in 200 runs out of 689 total runs for the Tigers in 2015, so he had a 29% RPI%.  

In Table 1, it is seen that White Sox outfielder Jose Abreu led the American League with a 33.3 RPI%. The National League leader was Nationals slugger Bryce Harper with 34.3% (Table 2). Kinsler and right fielder JD Martinez paced the Tigers with 29% (Table 3).

Table 1: AL Runs Participated In Leaders, 2015

Player	Team	Team Runs	RPI	RPI%
Jose Abreu	CHA	622	207	33.3
Eric Hosmer	KCA	724	226	31.2
Kendrys Morales	KCA	724	219	30.2
Robinson Cano	SEA	656	197	30.0
Chris Davis	BAL	713	214	30.0
Mike Trout	ANA	661	194	29.3
Josh Donaldson	TOR	891	261	29.3
Shin-Soo Choo	TEX	751	219	29.2
Ian Kinsler	DET	689	200	29.0
J.D. Martinez	DET	689	200	29.0
Prince Fielder	TEX	751	216	28.8
Adam Eaton	CHA	622	178	28.6
Xander Bogaerts	BOS	748	213	28.5
Lorenzo Cain	KCA	724	205	28.3
Michael Brantley	CLE	669	189	28.3

Data source:Retrosheet

Table 2: NL Runs Participated In Leaders, 2015

Player	Team	Team Runs	RPI	RPI%
Bryce Harper	WAS	703	241	34.3
Anthony Rizzo	CHN	689	228	33.1
Andrew McCutchen	PIT	697	220	31.6
Matt Kemp	SDN	650	205	31.5
Paul Goldschmidt	ARI	720	227	31.5
Joey Votto	CIN	640	198	30.9
Kris Bryant	CHN	689	205	29.8
A.J. Pollock	ARI	720	214	29.7
Nolan Arenado	COL	737	219	29.7
Matt Duffy	SFN	696	203	29.2
Matt Carpenter	SLN	647	185	28.6
Buster Posey	SFN	696	198	28.4
Todd Frazier	CIN	640	181	28.3
Starling Marte	PIT	697	196	28.1
Ryan Braun	MIL	655	184	28.1

Data source:Retrosheet

Table 3: Tigers Runs Participated In Leaders, 2015

Player	Team Runs	RPI	RPI%
Ian Kinsler	689	200	29.0
J.D. Martinez	689	200	29.0
Miguel Cabrera	689	169	24.5
Nick Castellanos	689	135	19.6
Yoenis Cespedes	689	132	19.2
Victor Martinez	689	125	18.1
Anthony Gose	689	121	17.6
Rajai Davis	689	98	14.2
Jose Iglesias	689	94	13.6
James McCann	689	87	12.6
Andrew Romine	689	58	8.4
Tyler Collins	689	58	8.4
Alex Avila	689	42	6.1
Jefry Marte	689	20	2.9
Dixon Machado	689	15	2.2

Data source:Retrosheet