Probabilistic Model of Range Revisited

I ‘ll continue the 2006 fielding analysis today by revisiting David Pinto’s Probabilistic Model of Range (PMR). I previously discussed PMR in reference to team fielding statistics. In short, the PMR system uses play by play data from Baseball Information Solutions (BIS) to determine how many plays a player made in relation to how many he was expected to make. Estimation of expectation takes into consideration factors such as: location of ball, how hard the ball is hit (soft, medium, hard), type of ball hit (e.g. ground ball, fly ball, line drive), handedness of batter and pitcher and ballpark. Pinto, himself, explains the whole PMR system in more detail on YouTube.

PMR is similar to zone rating but there are some differences. First, zone rating (ZR) uses data from STATS, Inc rather than BIS. Any play by play data collection involves a certain degree of subjectivity, although both companies train their video scouts to be as consistent as possible. I’m not sure whether one data collection system is better than the other. One advantage the PMR system has over zone rating, however, is that it treats balls in different parts of the zone differently. Pinto considers some balls in a zone to be more difficult to reach than others and he takes this into consideration in his algorithm.

The PMR statistics for Tigers regulars in 2006 are shown in Table 1 below. I’ll use Brandon Inge’s numbers to explain how the table should be read. There were 4,278 balls in play all over the field when Inge was playing third base. He successfully turned 506 balls in play into outs. The PMR algorithm predicted that 480 plays would have been made successfully. Therefore, Inge made 26 more plays than would be expected by the average third baseman. Inge’s 105.47 out ratio indicates that he made 5.47% more plays than expected. He ranked sixth out of 30 Major League third basemen with 600 or more innings.

The Tigers did not rank as high on PMR as on Chris Dial’s Run Saved (RS) statistic but several of them still ranked very well. The one Tiger who was ranked better by PMR was Guillen who ranked 7th out of 30 shortstops. Other Tigers ranking above average were Chris Shelton (11/27), Placido Polanco (11/29), and Curtis Granderson (9/27). Three players ranked very low on this system: Sean Casey (27/27), Craig Monroe (26/28) and Magglio Ordonez (25/27).

Table 1: PMR Stats for Tigers Fielders in 2006

POS	Player	#	BIP	Outs	Pred outs	Diff	ratio	PMRRank	RS Rank
1B	Shelton	27	2737	179	175	4	102.00	11	1
1B	Casey	27	2806	168	189	-21	88.77	27	4
2B	Polanco	29	2838	373	363	10	102.66	11	2
3B	Inge	30	4278	506	480	26	105.47	6	2
SS	Guillen	30	3808	465	449	16	103.49	7	13
LF	Monroe	28	2909	168	179	-11	94.05	26	14
CF	Granderson	27	4014	385	376	9	102.39	9	9
RF	Ordonez	27	3893	258	269	-11	96.00	25	17