This one is based on the system used at Baseball Prospectus. I adjust WARP for season-length, as described in the normalization post.
WARP stands for Wins Above Replacement Player, and you can read more at Baseball Prospectus. They have three versions of WARP: 1, 2 and 3. WARP1 is the basic measure. WARP2 "timelines" the WARP1 score, to account for the higher talent levels in modern baseball. WARP3 then adjusts WARP2 for season-length.
I do not timeline. I measure players in the context in which they played, not the modern context. That's why I use WARP1, and then independently apply a season-length adjustment. In a way, it is like WARP3, but skips WARP2.
I give an individual grade for each of the following: 3-year peak; 5-year consecutive peak; 7-year peak; WARP1 per 162 games (or WARP1 per 100 IP for pitchers); and career WARP1. My goal is to blend peak measures with career totals. So in addition to giving grades in those areas, I also have a combo formula that gets a grade. The combo formula consists of taking the square root of the product of WARP1 per 162 games (or WARP1 per 100 IP) times career WARP1.
For each position played, and each of those WARP1 categories, I examined the numbers achieved in those categories by actual Hall of Famers (categorized by position) and developed a scale to apply to the players under evaluation. After applying the grades in those categories, I end up with a WARP1 GPA, which determines the grade that goes into the player's overall GPA.
My WARP1 grade gets 1.5 times the normal weight in the GPA, because it is one of the preeminent uber-systems. Unlike Win Shares, I do not give a separate grade for WARP1 defense. Maybe someday I will.
