Basic Hitting Metric Correlation 1955-2012, 2002-2012
The distinction between observed performance and true talent is one that is, in a way, intuitive, yet tends to be elusive. Even the most careful of us can slip from talking of one to talking of the other. Determining the difference for a specific skill or a specific player can be difficult, but the general idea itself is not so hard to understand. Even the most casual fan of baseball understands that pretty much any player can go 0-4 or 4-4 in any given game without thinking that player’s true talent batting average is either .000 or 1.000. That understanding already contains the basic notion of a proper sample size and its relation to true talent. The reader can peruse the appropriate sections of the Sabermetric Library to get caught up.
Instead, this post is going to look at some specific metrics for hitters (in the near future I may do a similar post for pitchers) and compare how well they correlate from from year to year. This gives us an idea of how these assorted metrics compare (relative to each other) with respect to predicting a player’s future performance (another way of saying true talent). I have included a couple of tables for reference, along with some brief commentary.

