PER Sports MLB Stats

American League 2008 Pitching PER Analysis (through ALL games of 2008)

Rank PLAYER TEAM Pitching PER Winning Percentage Earned Run Average Opposition On Base Ave Unearned Run Average Walks to Strike Out Ratio

1 Mariano Rivera NYY 84.94 54.55 1.40 0.188 0.00 0.08

2 Joe Nathan MIN 82.31 33.33 1.33 0.237 0.40 0.24

3 Joakim Soria KCR 81.07 40.00 1.60 0.241 0.13 0.29

4 Grant Balfour TBR 80.59 75.00 1.54 0.229 0.00 0.29

5 Jonathan Papelbon BOS 80.04 55.56 2.34 0.241 0.78 0.10

6 Brad Ziegler OAK 78.94 100.00 1.06 0.281 0.15 0.73

7 Jose Arredondo LAA 78.52 83.33 1.62 0.262 0.59 0.40

8 Scott Downs TOR 77.44 0.00 1.78 0.286 0.13 0.47

9 Cliff Lee CLE 76.96 88.00 2.54 0.274 0.20 0.20

10 Matt Thornton CHW 76.93 62.50 2.67 0.255 0.00 0.25

11 Jesse Carlson TOR 76.84 77.78 2.25 0.265 0.15 0.38

12 Francisco Rodriguez LAA 76.73 40.00 2.24 0.305 0.53 0.44

13 Rich Harden OAK 76.45 83.33 2.34 0.278 0.12 0.34

14 Roy Halladay TOR 76.34 64.52 2.78 0.269 0.44 0.19

15 Bobby Jenks CHW 76.13 75.00 2.63 0.272 0.00 0.45

16 J.P. Howell TBR 76.02 85.71 2.22 0.282 0.71 0.42

17 Justin Duchscherer OAK 75.95 55.56 2.54 0.260 0.32 0.36

18 Hideki Okajima BOS 75.56 60.00 2.61 0.282 0.00 0.38

19 Joba Chamberlain NYY 75.36 57.14 2.60 0.298 0.27 0.33

20 Darren Oliver LAA 74.95 87.50 2.88 0.287 0.13 0.33

21 Ramon Ramirez KCR 74.88 60.00 2.64 0.290 0.25 0.44

22 Dan Wheeler TBR 74.73 45.45 3.12 0.249 0.27 0.42

23 Jim Johnson BAL 74.72 33.33 2.23 0.292 0.13 0.74

24 Frank Francisco TEX 74.68 37.50 3.13 0.278 0.28 0.31

25 Ervin Santana LAA 74.20 69.57 3.49 0.278 0.16 0.22

26 Mike Mussina NYY 74.11 68.97 3.37 0.296 0.45 0.21

27 B.J. Ryan TOR 74.04 33.33 2.95 0.310 0.31 0.48

28 Manny Delcarmen BOS 73.84 33.33 3.27 0.278 0.12 0.39

29 Brian Tallet TOR 73.81 33.33 2.88 0.307 0.16 0.47

30 Rafael Perez CLE 73.76 50.00 3.54 0.287 0.24 0.27

*Based on at least 50 innings pitched within league

PER Analysis of the All-Time Greatest Hitters in MLB History

PER Analysis of the All-Time Greatest Pitchers in MLB History

Revolutionary Baseball Pitching Efficiency Rating
This analysis determines the best pitchers in baseball irrespective of their pitching roles. The construct evaluates the statistics of ERA, Opposition On base Average, and Walks to Strike Out ratio.

Earned Runs Average is widely understood to be one of the most important statistics used to evaluate a pitcher. It shows how many earned runs a pitcher yields for every 9 innings pitched. Alongside the ERA PER Sports includes a statistic called UnERA which measures the number of unearned runs given up by a pitcher per 9 innings. It shows how well a pitcher can pitch around mistakes and therefore partially indicates the mental fabric of the pitcher.

Opposition On Base Average is a very important statistic (almost as important as the ERA) since it indicates the number of base-runners a pitcher allows per inning pitched. This is a more comprehensive measure than Opposition Batting Average since pitchers who are wild and walk or hit a lot of batters will not be accurately captured in the Opposition Batting Average stat.

Walks to Strike-Out Average is a measure of the level of dominance and control exhibited by the pitcher. High Strikeouts reflect pitching dominance and low walk totals speak to impressive control.

This statistic ignores all decision statistics (i.e. winning percentage, save percentage, or hold percentage) since winning percentage for eg. depends a lot on the amount of run support a pitcher receives (which is itself a function of his opposing pitcher on the mound). As such it may not be a true reflection of their pitching performance. Likewise, the save percentage does not take into account the quality of saves by that closer, i.e. giving up only one or zero runs per save opportunity.

In addition, in order to minimize the bias that generally occurs with pitching too few innings, the statistic adjusts for pitchers with more Innings Pitched. This measure is therefore an efficient method of determining the annual Cy Young Award winner.

Interpreting the PER Baseball Score
Since a value of 100 represents the ceiling on a pitcher's rating (and that for a truly perfect pitcher, i.e. the score for a perfectly pitched game) then the following rating guide applies:

		Between 90 and 100 indicates a truly Legendary Pitcher/Performance
		Between 85 and 90 indicates an Excellent Pitcher
		Between 75 and 85 indicates a Superior Pitcher
		Between 65 and 75 indicates an Average Pitching Performance
		Between 60 and 65 indicates a Below Average Performance
		Below 60 indicates a Poor Pitching Performance

PER Hitting Analysis of the 2007 NL Season

PER 2007 AL Pitching Analysis

PER 2007 NL Pitching Analysis