Football Rating Model: Probability of Win, Loose or Draw

[luxxio]

i am wondering about how it is possible compute the probability of win, loose or draw in football game or any other sport. who knows the model the bookmaker use? and which level of confidence they have?

 

[zli034]

Bookmaker use bayesian belief to update the winning odds. And in order for the bookmaker to earn no matter what game outcome can be they have a technique called dutchbook which means sum of the probability less than 1.