I'd suggest to read this:
Odds Probability Calculator[
^]
Quote:
Probability Formulas:
This calculator will convert "odds of winning" for an event into a probability percentage chance of success.
Odds, are given as (chances for success) : (chances against success) or vice versa.
If odds are stated as an A to B chance of winning then the probability of winning is given as PW = A / (A + B)
while the probability of losing is given as PL = B / (A + B)
.
So... i'd store all wins per team:
Game No. Count of wins Sum of wins Chances for win
TEAM A TEAM B TEAM A TEAM B TEAM A TEAM B
1 1 0 1 0 100,00% 0,00%
2 1 0 2 0 50,00% 0,00%
3 0 1 2 1 0,00% 100,00%
4 0 1 2 2 0,00% 50,00%
5 1 0 3 2 33,33% 0,00%
6 0 1 3 3 0,00% 33,33%