Wednesday, June 19, 2013

Primer to SPEC for Evaluating Prospects

Intro 

One of my ambitions as a prospect writer has been to create a projection system that combines scouting reports and statistical analysis. The war between scouts and number guys in Major League Baseball has been in the media a lot lately, albeit greatly overblown. With that said, both sides bring very different views to the table, and I think you need both when evaluating a player. I think this is even more important with prospects.

Earlier this week I introduced the concept of SPEC in this post breaking down highly touted Cubs prospects Javier Baez and Jorge Soler. I really liked the idea, but the more I played around with it, the more flaws I discovered. I felt that WAR wasn't the right metric to use because I am not really concerned with the win value of a minor league player. I am instead looking for a metric that will measure the players complete offensive performance to project future performance. Furthermore, the WAR calculator I was using was very easy to understand, but not quite as precise for I would have liked. I found my self making too many educated guesses when evaluating factors like a players defense and base running abilities, which defeats the purpose of an exact statistic.

 wRC+
The statistical component of SPEC will be based Tom Tango's of sabermetric wRC+. Weighted Runs Created Plus is the best way to gauge a players total offensive value. wRC+  is derived from wOBA but also takes into account factors like league environments and ballpark tendencies. It is based off a scale, where 100 is average. Anything above 100, is the percent of runs above league average that a player produced. Conversely, anything below 100 is the percent of runs created below the mean. A players wRC+ can be found on their player page on Fangraphs. For a more detailed examination of wRC+ checkout the following links:
-http://www.fangraphs.com/library/offense/wrc/
-http://www.ball-four.com/post/14866772175/stat-of-the-week-wrc-weighted-runs-created-plus
Positional Value
The one component of WAR that I did like and want to carry over into SPEC is the positional value. A players ability to profile and remain at a premium position is a key element of prospecting. A lot of guys will be drafted as shortstops and center fielders, but most have to move off the position at some point down the line.
This list ranks the added value each position brings and show the amount of runs each position is worth over the course of a 150 game season. I want position value to affect the SPEC significantly, so  add or subtract the run values from a wRC+ accordingly.
  1. C: +10 runs
  2. SS: +8.0 runs
  3. 2B: +3 runs
  4. CF: +2.5 runs
  5. 3B: +2 runs
  6. RF: -6.5 runs
  7. LF: -8.0 runs
  8. 1B: -10 runs
  9. DH: -15 runs

Risk Factor
Less than eight percent of players selected in the draft will every get more than a cup of coffee in the major leagues, so every prospect carries a great deal of risk. Ones that are in the lower minors or ones that lack polish are especially risky. And while all prospects develop differently, one way to discern between a prospect that is considered "risky" and one that is considered "safe" is by looking at their strikeout rate compared to the rate at which they draw walks. This will indicate how advanced their approach is and how much development they need to make contact at the big league level. For the purpose of SPEC, the SO-BB ratio of each player will be compared to that of the average ratio between strikeouts and walk percentage which is about 2.3 to 1. For every 0.2 a player is above the average, his risk factor will decrease by 0.01. So if the ratio between a players strikeout and walk percentage is 2.5, one would multiply his SPEC by 0.99. The opposite is also true. If a players ratio is 2.1 one would multiply his SPEC by 1.01. The factor will not really affect the majority of players, but it will punish those that have terrible approaches and strikeout at a really high clip. 

Age Versus Level
Possibly the most intriguing aspect of SPEC is the inclusion of an age vs. level factor. When projecting the futures success of a prospect it is all about development. Nine times out of ten, if a teenager holds his own in full season ball and puts up league average numbers he will be a better prospect than the 23 year old in the same league who might have slightly better stats. Even a year can make a huge difference in the development as a prospect  matures physically and develops a more advanced approach mentally. Time really is everything for baseball players. The following table with the average age of each minor league level is shown below. Additionally, the factors that will be used are also featured. After you have made this calculation, divide by ten for final statistical component.
Level
Average Age
1.5 years older
1.0
Year older
0.5 year  older
0 years older
0.5 year younger
1.0 year younger
1.5 years younger
2.0  years younger
AAA
24.5
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.3
Multiply by 1.4
AA
23.5
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.3
Multiply by 1.4
A+
22.0
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.3
Multiply by 1.4
A
21.5
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.3
Multiply by 1.4
A-
21.0
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.2
Multiply by 1.4
Rookie
19.5
Multiply by 0.7
Multiply by 0.8
Multiply by 0.9
Multiply by 1.0
Multiply by 1.1
Multiply by 1.2
Multiply by 1.2
Multiply by 1.4

The Scouting Side
After finding the statistical component of SPEC, there is now a scouting side. For decades scouts have used the traditional scouting scale which ranges from 20 (worst) to 80 (best). The scale is increased by increments of 5, and 50 is considered to be major league average. Scouts evaluate the potential of  five key tools when looking at a hitter: their contact, power, speed, defense, and arm. When the individual grade of each tool is added and then divided by 5 you get your Overall Future Potential (OFP). But their are lots of other things scouts look at when they evaluate a player; like their intangibles, feel for the game, athleticism, and approach. For anything that makes a player standout, scouts use adjusted OFP. Scouts can either bump or lower a players OFP by up to 10 points (but not usually that much) based on what catches their eye.

Once you have a players adjusted OFP you need to divide it by 10, unless you are already using the abbreviated 2-8 scale. Finally, you need to raise that number to the e. This number is the Evaluation part of SPEC.

For more reading on the OFP give this is a read.

Combination
Now that you have your scouting and your statistical totals, all you have to do is add them together. This is your SPEC number. If this is confusing now, I promise that there will be tons of examples in the coming months, as I plan to use it in all of my evaluations. You will be sick of it soon.

Rob Balboni

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