Which Right Fielders Made The Best And Worst PIZAA in 2014?

Tiger right fielder Torii Hunter had limited defensive range in 2014
(Photo credit: Tattoos.fanshare.com)

Most of the readers of this blog are aware of the advanced fielding statistics at sites like FanGraphs and Baseball-Reference.  A metric such as Defensive Runs Saved (DRS) gives us an idea of a player’s overall fielding performance.  It is given as runs saved above what would be expected from the average player at the given position.  It is discussed in more detail in the fielding glossary.

You may also have noticed two additional columns at FanGraphs labeled RZR and OOZ.  These are the Revised Zone Rating statistics developed by John Dewan, president of Baseball Info Solutions.  Dewan later developed the more detailed DRS metric.  The Revised Zone Rating system is comprised of the following measures:

1. Balls in play within a fielder’s zone (BIZ)
2. Plays made in the zone (Plays)
3. Proportion of balls in zone converted into outs (RZR)
4. Plays made outside the zone (OOZ)

A play is considered to be inside a positional zone if half the balls hit into that area are converted into outs by all the players in baseball at that position.  While the Revised Zone Rating system is less sophisticated than DRS, it is useful because it separates the plays a player made inside his zone from the plays outside his zone.  Unlike DRS, the Revised Zone Rating system includes all shift plays and is thus is not easily interpreted for infielders.  It is more useful for evaluating outfield defense which is less influenced by shifts.

Table 1 below shows how the distinction between in-zone and out-of-zone plays can be useful.  Mets right fielder Curtis Granderson converted 180 out of 207 (87.0%) of balls in his zone into outs in 2014.  Nationals right fielder Jayson Werth had a similar number of balls hit into his zone (204) but had a higher RZR (93.1%).  Conversely, Werth made fewer out-of-zone plays (58) than Grandrson (85).  These data suggest that Werth may have been the steadier fielder on balls hit in the right field zone but that Granderson was better at making difficult plays.

Table 1: Revised Zone Rating Statistics for Curtis Granderson and Jasyson Werth, 2014 

Player	BIZ	Plays	RZR	OOZ
Curtis Granderson	207	180	.870	85
Jayson Werth	204	190	.931	58

 Data source: FanGraphs.com  

Some readers may have wondered whether these statistics could be translated to runs above average like most of the other defensive metrics.  A few years ago, Colin Wyers (who has since been hired by the Houston Astros) developed an algorithm which combined RZR and OOZ and translated these numbers into plays made above average (PMAA) and runs saved above average (RSAA).  Wyers' algorithm has a lot of steps and I'm not going to repeat the whole process here.  If you want see all the math, you can read my post from two years ago.

Table 2 below shows the MLB leaders among right fielders in 2014.  The top right fielder in the majors was Jason Heyward of the Braves with 44 PMAA. The 44 plays made can be broken down into two parts: 4 Plays in Zone Above Average (PIZAA) and 40 Plays Out of Zone Above Average (OOZAA).  PIZAA and OOZAA may be two of the most amusing acronyms out there and you are probably relieved that I didn't show all the math.  Simply stated though, Heyward was little above average on plays in the right field zone and exceptional outside the zone.

The final column of the table shows that Heyward saved an estimated 37 runs for the Braves.  Heyward was also rated as spectacular by DRS (+32),Baseball-Reference's Total Zone (+30) and Baseball Prospectus' FRAA (+27).  

The worst right fielder according to this metric was Torii Hunter who cost the Tigers an estimated 19 runs with his defense.  Thus, the Tigers theoretically could have gained two wins if Hunter had been just an average right fielder.  Hunter had -3 PIZAA and -20 OOZA which shows that he was particularly bad on plays made outside the right field zone.  These data are further evidence  that Hunter's poor fielding offset most of the offensive production that he provided.    

Table 2: Runs Saved by MLB Right Fielders According to RZR, OOZ, 2014

Player	Team	Inn	RZR	OOZ	PIZ AA	OOZ AA	PMAA	RSAA
Jason Heyward	ATL	1,317	.917	122	4	40	44	37
Marlon Byrd	PHI	1,337	.912	102	2	18	21	18
Giancarlo Stanton	MIA	1,262	.907	97	1	18	19	16
Josh Reddick	OAK	873	.936	62	5	7	12	10
Alex Rios	TEX	962	.904	72	0	12	12	10
Hunter Pence	SFG	1,425	.930	94	6	5	11	10
Jose Bautista	TOR	1,080	.889	80	-3	13	10	8
Curtis Granderson	NYM	1,177	.870	85	-7	11	5	4
Nori Aoki	KCR	937	.915	59	2	0	2	2
Ichiro Suzuki	NYY	811	.919	49	2	-2	1	0
Gerardo Parra	- - -	921	.911	50	1	-8	-6	-5
Ryan Braun	MIL	1,165	.913	64	2	-9	-6	-5
Nick Markakis	BAL	1,314	.872	78	-8	-4	-12	-10
Jayson Werth	WSN	1,220	.931	58	6	-18	-12	-10
Kole Calhoun	LAA	1,036	.896	50	-1	-15	-16	-14
Oswaldo Arcia	MIN	846	.868	40	-6	-13	-19	-16
Jay Bruce	CIN	1,136	.935	44	7	-27	-20	-17
David Murphy	CLE	989	.896	40	-1	-22	-23	-19
Torii Hunter	DET	1,114	.885	50	-3	-20	-23	-19

 Data source: FanGraphs.com