Improvement in Winning Percentage

In an earlier post, I calculated the expected runs that would be scored by a team using linear weights and an optimal assignment of plate appearances between the players on the team. I found that the expected number of runs scored would increase from 90 in 2012 to 104 in 2013.

In another earlier post, I calculated the expected number of runs allowed based on a linear model of the pitchers and an equitable distribution on innings for each pitcher. I found that the expected number of runs allowed in 2013 is 120.

Also in an earlier post, I described the Pythagorean formula to estimate the win percentage from the runs for and against.

If I assume that the other teams in the league do nothing to improve while team G optimizes the plate appearances and pitchers innings, I can estimate the number of runs for and against for the 7 teams in 2013 based on the runs for and against in 2012 and the improvement of team G.

Below is a table which shows the estimated win percentages for the 7 teams in 2013 based on the runs for and against estimated for 2013.

	2012		2013
Team	RF	RA	RF	RA	Win Pct
A	109	59	109	61	0.765
B	94	81	94	83	0.562
C	92	86	92	88	0.521
E	106	113	106	116	0.456
G	90	119	104	120	0.429
D	74	84	74	86	0.425
F	79	102	79	105	0.364

We can see that in 2013, team G would move to 5^th place in the standings based on estimated win percentage.