This is a follow-up report to a FanPost published here a few weeks ago that examined how John’s pre-2013 A, A-, B+, and B starting pitcher prospects had performed during the 2012 season at 4 fielding- and ballpark-independent outcome statistics relative to their league and level peers. Now let’s take a brief look at how that group of arms has done so far in 2013 as judged via the same method.
Starting pitchers who: 1) received a B, B+, A-, or A grade from John Sickels in his pre-2013 prospect rankings, and 2) had faced at least 150 minor league batters during 2013 above the two transitional rookie leagues (Gulf Coast League and Arizona League) prior to July 16. The 2013 data was manually compiled from the MLB Advanced Media archived web data.
The four statistics are as before and more details regarding them can be found in the prior FanPost:
- BB&HBP%: The sum of walks and hit batsmen, divided by plate appearances against.
- K%: Strikeouts, divided by plate appearances against.
- LD&OFFB%: The sum of line drives and outfield flyballs surrendered, divided by the number of nonbunted batted balls.
- OFLD&OFFB Pull%: The number of line drives and flyballs hit to the batter’s pull-field third of the outfield, divided by the total number of line drives and flyballs hit to outfield.
Computation of Rating Scores
Performance scores are generated for each stat based on how many standard deviations (SD) better or worse the pitcher was versus the mean of same-handed "starters" who pitched at the same level (High A, for example) during 2012 (I am temporarily using the final 2012 data sample for each level rather than the evolving 2013 data as each pitcher’s reference group for several reasons and to save time especially). A 50 performance score signifies level-average performance, with a score above 50 indicating better than level-average performance and each 10 points equaling 1 SD. For those who prefer percentiles over a scouting-rooted scheme, a 2 SD better than level-average score (70 Score) amounts to the 97th percentile (pitcher is equaling or bettering 97% of level peers), 1 SD better than level-average (60 Score) amounts to the 84th percentile, level-average (50 Score) amounts to the 50th percentile, 1 SD worse than level-average (40 Score) amounts to the 16th percentile, 2 SD worse than level-average (30 Score) amounts to the 3rd percentile. Besides those 4 individual performance scores, an Overall Score is generated by weighting the 4 scores (20% BB&HBP Score, 36% K Score, 21% LD&OFFB Score, 23% OFLD&OFFB Pull Score) and scaling the result away from 50 such that 10 points equates to 1 SD. For reference, an Age Score is also computed for each pitcher by determining how many SD younger each is now versus what was average for a starter at the same level(s) during the 2012 season.
Study Group Changes
Fifteen pitchers dropped out from the 2012 study group based on falling below the 2013 minor league batters faced threshold: Julio Teheran, Shelby Miller, Trevor Rosenthal, Justin Grimm, Wily Peralta, Dan Straily, Tony Cingrani, Jose Fernandez, Danny Hultzen, Dylan Bundy, Cody Buckel, Nick Maronde, Kyle Crick, Michael Fulmer, and Luis Heredia. At the same time, 10 pitchers are newly eligible for 2013 having met the batters faced requirement for this season after not facing enough the prior season to qualify for the 2012 analysis: Kevin Gausman, Kyle Gibson, Marcus Stroman, Kyle Zimmer, Andrew Heaney, Lance McCullers, Chris Stratton, Max Fried, Jose Berrios, and Michael Wacha.
Top Performers per Overall Score
The table below features the top 28 of the 55 qualified pitchers sorted by Overall Score, with the relative percentage of level peers equaled or bettered in parentheses. Dark green denotes performance that is 2 SD better than level-average, light green denotes 1 SD better than level-average, dull yellow denotes 1 SD worse than level-average, and bright yellow 2 SD worse than level-average.
Alex Meyer edged the also-injured (and barely-2013-eligible) J.R. Graham for top honors by a few tenths of a point. Kevin Gausman and Noah Syndergaard also grade out as more than 2 SD better than level-average.
Of the other 27 qualified pitchers, 10 of them grade out as below-level-average Overall Score performers in 2013 (versus the final 2012 data for their 2013 level or levels). Daniel Corcino grades out as the worst by a wide margin at almost 2 SD below level-average in Overall Score.
Risers and Fallers
So how have the pitchers who have 2013 scores as well as 2012 scores changed since a year ago? In these tables, the number of points by which their scores have increased are found within parentheses, provided they had enough 2012 data to reference. Dark green denotes a 2 SD rise in score versus 2012, light green denotes a 1 SD rise versus 2012, dull yellow denotes a 1 SD fall versus 2012, and bright yellow denotes a 2 SD fall versus 2012.
Although Archie Bradley would still rate as below level-average in terms of control, his 21 point improvement in BB&HBP Score is the highest such rise in that metric. Sonny Gray has climbed to the near the top of the Overall Score ranks mostly on the strength of a tremendous 28 point increase in K Score. Large improvements in the 2 batted ball metrics pushed J.R. Graham up to the number 2 spot in Overall Score before he was felled by injury, and Graham edges Gray by a point in terms of the largest improvement in Overall Score versus 2012. Taijuan Walker joins Graham and Gray as another noteworthy 2013 riser. Syndergaard has seen his Overall Score drop only slightly versus his second-place 2012 total and now ranks 4th in 2013.
Several pitchers on the second list have had their Overall Score drop between 15 and 18 points, with the biggest belonging to Clayton Blackburn. Blackburn had the top Overall Score in 2012, and thus he still rates rather well for 2013 despite the decline in performance.
Capture of 2013 data remains ongoing, and at the conclusion of the minor league year these pitchers will be compared to their 2013 peers rather than the pitchers who pitched at the same levels during 2012; whatever differences exist now between the 2012 and 2013 peer groups would not be expected to cause a pitcher’s current score at any of the metrics to be off by more than a handful of points. Study as to how pitchers’ scores change in jumping from the minors to majors makes sense at some point as more continue to graduate and stick in the big leagues.