There are always plenty of changes in prospect rankings from one year to the next, but some things do manage to remain the same. The qualifications for the TigsTown prospect rankings follow the Major League Baseball rookie eligibility guidelines. Players must have spent less than 45 days on the active big league roster outside of September, and have less than 130 plate appearances or 50 innings pitched outside of September, to qualify for the rankings. These restrictions eliminate prospects such as Clay Rapada, Clete Thomas, and Matt Joyce from consideration, as they have exhausted such rookie standards.
This year's list remains as evidence of the prospect departures from the 2007 rankings. Names missing from the list – outside of those mentioned above – include Cameron Maybin, Dallas Trahern, Eulogio De La Cruz, Yorman Bazardo, Burke Badenhop, Andrew Kown, Randor Bierd and Brandon Johnson. While he isn't gone, don't be fooled by the absence of Edward Reynoso, whose real name turned out to be Darwin De Leon.
The departure of prospects like Joyce, Thomas, Maybin, Trahern, and DLC are hits to a system that was on the verge of being considered one of the strongest in baseball; and those hits are readily apparent in the steep drop-off in talent seen as one moves down the list.
As has been the case for the last several years, the TigsTown rankings are based on a proprietary formula that balances both scouting scores and the statistics a player posts in their game action. In past years, this scoring system has weighted the scouting metric and the statistical metric an equal percentage, but with continued refinement of the system, it became apparent that an alternate weighting would yield more accurate results. For the 2008 rankings, we have altered this weighting, with a slight lean toward the scouting metric; a change that should result in a fairer representation for those toolsy players that are still learning to translate their skills to the diamond.
On the scouting side, hitters are graded on the 20-80 scouting scale in six different categories; hitting for average, hitting for power, plate discipline, speed, defense, and arm strength. These scouting scores are averaged to yield an overall scouting score for each individual player.
Pitchers are graded in similar fashion, with scores registering for their fastball, breaking ball, change-up, injury history and present mechanics, body/build, and command/control. This scouting score, for both hitters and pitchers, is one of two input parameters to the final score for each player.
The other input parameter is a cumulative statistical rating that is based on six categories for both hitters and pitchers. Pitchers are scored against the league average in the following areas; walks per nine innings, strikeouts per nine innings, hits per nine innings, home runs per nine innings, earned run average, and WHIP. Each pitcher is assigned a 20-80 score for each category, relative to their deviation from the league mean in each area.
Similarly, hitters are scored based on walk percentage, strikeout percentage, extra-base hit percentage, stolen base success rate, OPS, and batting average. Commensurate with the process outlined for the cumulative scouting metric, the individual statistical scores are averaged to provide each player with a singular stats score that is an input to the final rating.
If a player has accumulated less than 100 at-bats or less than 25 innings pitched at the minor league level, their statistical components are not counted to avoid extreme bias stemming from an excellent or particularly poor handful of game appearances. In these cases, only a players scouting score is used as an input to the final rating.
In addition to the prescribed and very regimented rankings above, there is a slight subjective side to these as well. In any ranking system, there must be a mechanism for providing balance to outliers of the system, and making up for pieces that may not be easily quantified within the statistical constraints of the raw rankings. Factors such as the age of a player at a given level versus the average age of his league, whether the player has shown a trend of improvement or regression in their performance, and even an adjustment to separate the value of relief pitchers versus starting pitchers.
Each of these factors carries an adjustment with them that can be applied where appropriate. If a player is old or young for their league, they can be given a bonus or deduction of up to five percent, commensurate with their deviation from the league average age. If a player has demonstrated a sound trend of improvement or regression, a factor of plus-or-minus up to five percent can be applied again, and for all relief pitchers, a mandatory five percent deduction is assessed in order to normalize the differences in sample size and mitigate how their scouting metrics may grade in only a couple of innings of work at a time. These factors are applied consistently across all prospects, and provide the balance needed to produce a sound prospect ranking list.
After all that, we end up with a set of rankings that has some fascinating aspects that merit discussion. Contrary to recent years, where you had a group of prospects in the top eight to ten that were cause for legitimate excitement, and fostered thoughts of a bright future of young talent in Detroit, this list requires a bit more imagination to make that leap.
Stay tuned for Part Two this weekend, where we'll go into more detail about the Top 50!