Branch Rickey’s Equation Fifty Years Later

This paper analyzes Branch Rickey's 1954 equation in a regression context. The results for 1934--1953 are consistent with Rickey's conclusions, and the equation holds up well when extended 51 years. Two of Rickey's main points were that on base percentage dominates batting average and that offense and defense are equally important, and these, along with the entire equation, are generally supported by the results. Rickey does seem to have been ahead of his time.