Pythagenpat
Encyclopedia
Pythagenpat is a formula created by David Smyth and "U.S. Patriot" which attempts to find the optimal exponent to use in the Pythagorean expectation
formula. There are two versions of the formula, each developed independently. One version is rpg0.29, developed by Patriot, and the other is rpg0.287, developed by David Smyth. It has been suggested that .28 might work better as an exponent, but it is unclear whether this is actually so.
The formula's name is derived from Baseball Prospectus
' Clay Davenport
's Pythagenport formula, which attempts to perform the same function. Davenport has endorsed the Smyth/Patriot or pythagenpat formula as "a better fit to the data."
One advantage that the Pythagenpat formula has over the Pythagenport formula is that, when rpg equals 1, the exponent given by Pythagenpat is also 1, which is not the case with pythagenport. One must be the only correct exponent in this situation because "if a team played 162 games at 1 RPG, they would win each game they scored a run and lose each time they allowed a run. Therefore, to make W/(W + L) = RX/(RX + RAX), X must be set equal to 1.
Pythagorean expectation
Pythagorean expectation is a formula invented by Bill James to estimate how many games a baseball team "should" have won based on the number of runs they scored and allowed. Comparing a team's actual and Pythagorean winning percentage can be used to evaluate how lucky that team was...
formula. There are two versions of the formula, each developed independently. One version is rpg0.29, developed by Patriot, and the other is rpg0.287, developed by David Smyth. It has been suggested that .28 might work better as an exponent, but it is unclear whether this is actually so.
The formula's name is derived from Baseball Prospectus
Baseball Prospectus
Baseball Prospectus is an organization that publishes a website, BaseballProspectus.com, devoted to the sabermetric analysis of baseball. BP has a staff of regular columnists and provides advanced statistics as well player and team performance projections on the site...
' Clay Davenport
Clay Davenport
Clay Davenport, a native of Hampton Roads, Virginia, now living in Baltimore, Maryland, is a baseball sabermetrician who co-founded Baseball Prospectus in 1996. He co-edited several of the Baseball Prospectus annual volumes and is a writer for BaseballProspectus.com...
's Pythagenport formula, which attempts to perform the same function. Davenport has endorsed the Smyth/Patriot or pythagenpat formula as "a better fit to the data."
One advantage that the Pythagenpat formula has over the Pythagenport formula is that, when rpg equals 1, the exponent given by Pythagenpat is also 1, which is not the case with pythagenport. One must be the only correct exponent in this situation because "if a team played 162 games at 1 RPG, they would win each game they scored a run and lose each time they allowed a run. Therefore, to make W/(W + L) = RX/(RX + RAX), X must be set equal to 1.