Who are the best starting pitchers of the past 60+ years? One way to answer that question is using RE24, the measure of how much a pitcher reduces his opponent’s’ run expectancy with each batter faced.
Starting from each of the 24 base-out states (ranging from nobody on, nobody out to to bases loaded, two out), there is an expected number of runs a team will score in the remainder of that inning, based on average hitters facing average pitchers. With the result of each plate appearance, a pitcher is credited with the resulting change in run expectancy (which can be positive or negative) less any runs allowed.
RE24, then, tells you how many runs a pitcher saved or cost his team relative to the average pitcher in the same base-out situations. Over the course of a career, the batters each pitcher faces will collectively approximate an average batter, allowing some reasonable basis for comparing different pitchers (with the possibly large caveat that RE24 does not adjust for park factors, team defense or other factors).
After the jump, the top 50 since 1950.
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