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The Win Probability Inquirer

The Situation					Win Probability
Runs/Game	Inning	Bases	Outs	Score Diff	Home Team	Visitors	LI
4.00	Bottom of the ninth	Runners on first and second	1	0	0.6987	0.3013	4.33
4.00	Top of the ninth	Bases empty	0	0	0.5000	0.5000	2.24

The Win Probability Added of the second situation is -0.1987 and the Situational Win (WPA/LI) is -0.046

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Just enter a few assumptions in the table below to return the win probability stats of a game situation. First, determine the sort of run environment you want to assume (for instance, more runs are scored at Coors Field, but less runs will be scored when a team's ace is on the mound). Then, select the specific situation: the base situation, the inning (for extra innings, simply choose the ninth), the number of outs, and the score from the home team's point of view (if they lead by say, 5-3, that's a positive two-run differential).

The output will include each team's win probability as well as the leverage index of the situation. The win probabilities are based on models, not empirical data. This is important, because empirical data is often "polluted" by situations and sometimes suffers from a small sample size. You can read more about win probability in this article and you can read about Leverage Index (LI) here. All data was provided by Tangotiger.

Pick the Situation
Set the Run Environment:	3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
Pick the base situation:	Bases empty Runner on first Runner on second Runner on third Runners on first and second Runners on first and third Runners on second and third Bases loaded
Which inning?	Top of the 1st Bottom of the 1st Top of the 2nd Bottom of the 2nd Top of the 3rd Bottom of the 3rd Top of the 4th Bottom of the 4th Top of the 5th Bottom of the 5th Top of the 6th Bottom of the 6th Top of the 7th Bottom of the 7th Top of the 8th Bottom of the 8th Top of the 9th Bottom of the 9th
How many outs?	No outs One out Two outs
What's the home team's lead?	-11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11

Or compare two different scenarios and calculate the Win Probability Added between the two:

	First scenario	Second scenario
Set the Run Environment:	3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5	3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
Pick the base situation:	Bases empty Runner on first Runner on second Runner on third Runners on first and second Runners on first and third Runners on second and third Bases loaded	Bases empty Runner on first Runner on second Runner on third Runners on first and second Runners on first and third Runners on second and third Bases loaded
Which inning?	Top of the 1st Bottom of the 1st Top of the 2nd Bottom of the 2nd Top of the 3rd Bottom of the 3rd Top of the 4th Bottom of the 4th Top of the 5th Bottom of the 5th Top of the 6th Bottom of the 6th Top of the 7th Bottom of the 7th Top of the 8th Bottom of the 8th Top of the 9th Bottom of the 9th	Top of the 1st Bottom of the 1st Top of the 2nd Bottom of the 2nd Top of the 3rd Bottom of the 3rd Top of the 4th Bottom of the 4th Top of the 5th Bottom of the 5th Top of the 6th Bottom of the 6th Top of the 7th Bottom of the 7th Top of the 8th Bottom of the 8th Top of the 9th Bottom of the 9th
How many outs?	No outs One out Two outs	No outs One out Two outs
What's the home team's lead?	-11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11	-11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11