Overview

While many professional scouts use a "tools" based system to evaluate players, that type of system is difficult for the average fan to use in comparing players. This is especailly true when comparing minor league players, whom most fans don't see at all until they reach the major leagues. This system of evaluation also is plauged by the perception problem. One person always sees something different than another person. The problem is exascerbated when that person is either a fan of the team (and wants his prospects to be the best) or an employee of the team (and NEEDS his prospects to be the best).

The Theory we work with here at DF is that if a player will be a quality major league starter it will show up in his minor league statistics if you look at them "correctly". This last point is obviously very important. Only by looking at statistics in the correct way can you gain any real insight into a players potential. The PPES is our shorthand way of looking at pitching prospects. Our hope is that it will allow the average fan to compare intelligently the value and potential of minor league pitchers. We hope you will find it useful. As always any suggestions for improvement will be appreciated..

How the System Works

The system ranks EVERY pitcher with more than 75 IP at any full season level of the minor leagues, (Low A or above). Each player is then compared to his league using 6 criteria:

1) his HR/IP (on-base average)
2) his K/IP (slugging percentage)
3) his K/BB (on-base average + slugging percentage)
4) his H/IP (secondary average)
5) his BB/IP 6) his age relative to the league


We also use an age scale to determine the optimmum age for a prospect at each level. A player should be no older than:

23 at AAA
22 at AA
21 at A+
20 at A

This scale helps to punish pitchers who are performing very well at a level where they are significantly older than their compeittion. For those of you who have trouble with this concept think of it as a College Freshman baseball player playing against the JV highschool team.  At the same time, a player performing well at a level in which they are younger then the rest of the competition is rewarded.

Our scale is slightly more liberal than others you will come across, some of which use 19 or 20 as the optimum age for a low A prospect. We think that this system is more fair to college players who are typically drafted and sign at 21 out of college and therefore are always behind the curve as they move up the rankings.

Any Pitcher who is more then 3 years older than the optimal age for the league are excluded from the rankings.

Score

The PPES score is calculated by taking a players stats and subtracting them from the corresponding league stats. These give us the Raw scores for each category.  For example:

Pitcher A has an pitching line that looks like this...

.057 HR/IP
6.00 K/BB
.897 K/IP
.644 H/IP
.149 BB/IP

vs. a league line that looks like this
.063 HR/IP
2.00 K/BB
.758 K/IP
.970 H/IP
.379 BB/IP

Obviously this pitcher is performing significantly better than the league averages. The System subtracts the league numbers from the pitchers and then uses a formula to calculate the players PA (pitching adjustment). This number represents the value of the pitchers production relative to his league. While the formula by which we calculate PA is very involved (e mail if you want the details), the total PA for this player would have been 20.501.

That means that this pitcher's achievements are worth 20.501 points on our scale of evaluation vs the league he was playing in. The context issue is important to remember because all leagues are not created equal.

The next step is to add this adjustement to a baseline number to produce a score. The number we use is 70.000. Why 70? After 5 years of using numbers from 55-75 in the hitters arena and 2 seasons of testing the pitchers category with numbers in a similar range, 70 produced the right spread of players across the categories. Adding the players score to this constant we get a unadjusted score of 90.501.

On our scale which we will discuss in a moment this pitcher would receive a A- grade and be considered a Very Good Pitching Prospect. However, we have yet to adjust the players score for his relative age. This is a critical part of the evaluation. Two pitchers with the same PA in the same league but years apart in age are not the same caliber of player.

The age adjustement we use is +/- 3 points for every year under/over the opitmum age for each league. So if our hypothetical player was 23 in AA his score would remain 90.501.   If he was 25 in AA with the same numbers, his score would be lowered by six points to 84.501 dropping him to a B prospect on the scale. If he was 21 in AA with the same
numbers, his score would be raised by 6 points to 96.501, moving him up into the rarified air of and A+ prospect. For pitchers who qualify at more than one level, we use the score from the highest level achieved.

Scale

The Official Gradihng Scale:

A+ 96-100 Cant Miss Pitching Prospect
A 92-96 Superior Pitching Prospect
A- 88-92 Very Good Pitching Prospect
B+ 84-88 Good Pitching Prospect
B 80-84 Solid Pitching Prospect
B- 76-80 Above Average Pitching Prospect
C+ 72-76 Average Pitching Prospect
C 68-72 Mediocre Pitching Prospect
C- 64-68 Suspect
D+ 60-64 Not Even a Suspect
D 56-60 Fire that Scout
D- 52-56 Why did we draft him again?
F below 52 Coaching material.

Players consistently below 72 on the scale should not be taken seriously as prospects. Each year the number of players below 72 is higher than those above it.

Points

The points ranking you see on the main prospect list is based on the total number of pitchers ranked in the given year. In 2006 570 total pitchers were ranked on this master list. HOWEVER For the Organizational Rankings Points are given only for pitchers/players whose score is better than a C+.

Other Notes

Things to remember when using this system particularly for pitchers.

1)The importance of AA: Many pitchers have dominant numbers in the lower minors that are more a function of the weak plate discipline of the hitters they face. Soft Tossing pitchers many times look like great prosepcts until they hit AA where the quality of hitters is much greater. Therfore in looking at this pitchers in this system always rememeber the importance of the AA filter in terms of pitching prospects. You should also read as much as you can find about the kind of stuff a particular guy throws from the various minor league publications you can find. That will alert you to possible over-ranking by a straight Statistical system like ours.

2) The Limits of the System: Since I use a 75 IP cutoff for pitchers several top prospects who move from level to level each season are going to missed. This is particularly true when a player is used primarily or exclusively as a relief pitcher. While most times we get at least one or two shots at ranking a pitcher before he makes the majors that may not always be the case. That does not mean we dont think the pitcher has great potential just that evaluating a pitcher with 40 IP of work is NOT a solid means of analysis using our system.