Good Statistics Versus Bad Statistics
By Taylor

This post is more of a reference or an index than a real, honest-to-gosh sabermetrics-analyzing post.
For those of you who aren’t sure what statistics to use when evaluating a player, look no further than this post. Feel free to disagree, but I believe that these are categorized correctly.
Good stats are those that measure a player’s actual talent or skill level in a certain area. Bad stats don’t account for luck or other such factors that get in the way of understanding a player’s true underlying skills and ability.
Good stats – use these to evaluate how good or bad a baseball player is:
- FIP (Fielding independent pitching)
- tRA (Park-adjusted, defense-adjusted, ERA-like stat)
- wOBA (Weighted on-base average)
- OBP (On-base percentage)
- SLG (slugging percentage)
- BA (batting average, and this one is debatable)
- UZR (ultimate zone rating)
- K/9 (strikeouts per nine innings)
- H/9 (hits allowed per nine innings)
- BB/9 (walks allowed per nine innings)
- BBs (walks accrued by either a pitcher or batter)
- Ks (strikeouts accrued by either a pitcher or batter)
- LD% (percentage of line drives hit by a batter of his total balls hit in play)
- GB% and FB% (percentage of ground balls or fly balls either hit by a batter or induced by a pitcher. Remember, ground balls are better because they are more likely to turn into outs.)
Bad stats – don’t use these to evaluate players for their skills:
- ERA (Earned run average; you may as well look at total runs allowed if you’re going to go down this dark, dark path. ERA is decent over a career sample, but not over anything smaller than that.)
- WHIP (So incredibly dumb that I won’t bother to explain it)
- VORP (which is pretty much WAR for cavemen)
- Defensive errors (this measures sure-handedness rather than defensive ability, and it certainly doesn’t measure range.)
- Saves (anyone can be a closer)
- Win-loss record (you should know better; anyone can win a baseball game if their team scores enough runs. Even Carlos Silva.)
- RBI (runs batted in; this measures your team’s ability to get on base more than a player’s ability to hit with men on base)
So there you go. Most of the good stats are available on www.Fangraphs.com and www.Statcorner.com.