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Win Expectancy Calculator

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Based on the number of runs scored, I have determined that the formula for win expectancy is the following: Win expectancy = 1-((1/(RS+4.5))^((RS^1.14)/14.1)) [?] RS = runs scored I discovered the coefficients of 1.14 and 14.1 by calculating the cumulative amount of deviation from normal win expectancies (1969-2011), weighted for instances of runs scored, using an extremely vast array of coefficients in MS Excel, effectively using what I like to call a "bowl apparatus". Based on the repetition of the formulas with varying coefficients, 1.14 and 14.1 gave me the lowest cumulative deviation value. Remarkably, even though this was done using data only from 1969-2011, the correlation is even stronger (using these same coefficients) when data is expanded to 1901-2011, and actually accounted for many of the biggest deviations! This suggests that the formula works just as well, if not better, for games before 1969. The link above will take you to Baseball-Reference's situation calculator - try this for yourself! The link below has the collected data. Win expectancy chart (with deviations)

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