Often in historical discussions, a sportscaster might bring up a player such as Roberto Clemente or Sandy Koufax. They will cite the player's first few seasons, noting that while they were a superstar player, they struggled in their first few seasons in the majors. Koufax is a particularly good example. He reached the Majors at the age of 19, and in his first six seasons posted a rather pedestrian record of 36-40. This type of analysis misses a key point. Most comparable players were not in the majors at ALL at that age. A great deal of players were not yet even in professional ball.
Koufax played early in the major leagues because he was a "bonus baby." A player who earned a large bonus as an amateur was required to spend two seasons on the major league roster. This rule was intended to prevent teams from hoarding top amateur talent. Clemente was actually a Rule V pick, again a player required to play in the minors at an early age.
Often we tend to evaluate players by looking at career rate stats. Quirks in early or late career performance can skew these results however. I feel it is appropriate to focus on player's primes to get a fair evaluation of their true abilities. This is not the end-all of evaluation. Rather, it simply provides a second look at the great players, allowing us to avoid inaccurate ratings simply because of a fluke in the data set.
Over the offseason, I plan to rate the top five in baseball history at each position. I plan to use statistics, era adjustments, non-MLB players (i.e. negro leaguers), and perhaps even raw skills. These ratings may come out differently than expected, but I hope to find it a worthwhile and enjoyable project.