Baseball is a tough game to predict, but there are a handful of advanced statistics these days that serve as a useful tool for forecasting player regression.
It’s by no means an exact science, and there are always exceptions to the rule, but the following statistics are good predictors of regression (definitions via FanGraphs):
- FIP (Fielder Independent Pitching): Measures what a player’s ERA would look like over a given period of time if the pitcher were to have experienced league-average results on balls in play and league-average timing. Looks at results a pitcher can control directly: strikeouts, walks, hit by pitches and home runs. A pitcher with an ERA significantly lower than their FIP is likely headed for regression.
- BABIP (Batting Average on Balls in Play): Measures how often a ball in play goes for a hit. Typically around 30 percent of all balls in play fall for hits, but there are several variables that can affect BABIP rates for individual players, such as defense, luck and talent level. Can indicate good luck for a hitter or bad luck for a pitcher.
- HR/FB (Home Run-to-Fly Ball Rate): Is the ratio of how many home runs are hit against a pitcher for every fly ball they allow. League average is around 10 percent and true talent for almost every pitcher is about 8-12 percent. Can indicate good luck for a hitter or bad luck for a pitcher.
These three statistics—along with track record and batter/pitcher tendency stats like strikeout and walk rate—will be focused on in this article, in an effort to identify 10 players who thrived in 2014 but could be headed for significant regression in 2015.
Obviously, this is not meant as an attack on any of these players, but instead an objective look at which players could be headed for the biggest drop-off in the upcoming season.