Analysis of football prediction methods

1. Introduction Football is one of the most popular sports in the world. Every day people watch matches all over the world. Consequently betting on the outcome of football matches is having a considerable interest by football supporters and simple betting fans. Every week a huge number of bookmakers offers an infinite amount of odds on the various results of a match. Bets can be placed on the final outcome, but also on the exact score, on the halfnulltime and fullnulltime results, on the margin of victory and so on. Furthermore, also thanks to the global diffusion of internet, in the last few years the sonullcalled “innullrunning betting” is getting more and more common among the betters since people can place a bet while they are following the match in progress. Unlike in the other types of betting, such as in horsenullracing, the odds are given around one week before the football matches are played. In this way we could make a detailed comparison of bookmakers' odds and identify who offers the most profitable odds for each match. That is why a statistical model able to accurately predict the probabilities of the outcome of football matches has the potential to create the basis for an optimal betting strategy. Various proposals have been made for modelling the outcome of football matches. For a good betting strategy, however, probabilities must be estimated on a teamnullspecific basis, so that the probabilities of the various match outcomes between two specific teams on a particular date can be calculated. The first complete model able to allow for the different team effects and also for the fluctuating performance of individual teams was made by Dixon and Coles (1997). The goals scored by the home and the away teams have different Poisson distributions and a sort of dependence between them is introduced. 8