Chapter Five – Offensive Evaluation

He demonstrated that, given a mean batting average of .270 and a standard deviation of .025, which is a reasonable estimate for a 500 at bat season (see just below), the amount of variance accounted for by a batter’s ability to hit for average on the batter’s odds of getting a hitting in a given at bat can be computed by (.025)2 (.270)(1-.270) ................
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