Football betting is a huge industry, with dozens of large bookmaking companies operating in Australia. Unfortunately for the average punter, these companies only exist because people lose money betting. One of the biggest mistakes people make betting on sports is that they like to bet on the team that they think is going to win. Seems reasonable, right? Wrong.
Who you think is going to win should not make the slightest difference to who you bet on.
That isn’t to say you should never bet on who you think is going to win, it means that you shouldn’t bet on a team just because you think they will probably win. Consider tossing a biased coin. It lands heads 90% of the time, and tails the other 10%. Now if I offer you some odds, do you know which way you will bet? If your answer is anything but “I can’t make a decision until I see the odds”, then you should think twice about gambling.
In order to profit from gambling we need to bet on the team which has favourable odds. As discussed above, this is not necessarily the favourite – in fact, a lot of the time the model will suggest betting on the underdog. For this strategy to work, bets and bet sizes must be chosen carefully. The way to choose how much to bet is,
Bet on the team with odds that will make profit in the long-run.
For instance, suppose Essendon are playing Carlton. Essendon have been traveling well, while Carlton are struggling to find form. The model gives Essendon a 70% chance to win the match, and Carlton a 30% chance. The bookmakers, however, think Essendon are an even better chance than that. They will only pay $1.22 for an Essendon win, and $4.88 for a Carlton win. In this case it is more favourable for us to bet on Carlton, even though we think Essendon will likely win. This is because if Carlton win this match 30% of the time, we will make a profit in the long-term by betting on them (0.3*4.88 – 1 > 0). However, if we bet on Essendon, we will lose in the long-term (0.7*1.22 – 1 < 0). This logic follows to even when teams are rank-outsiders. If Greater Western Sydney are only a 5% chance to win, but are paying $30, you can imagine that a very small bet on GWS is worth-while.
This can also apply to favourites. Suppose Essendon again have a 70% chance to beat Carlton, but are now paying $1.60. We will now want to bet on Essendon, because if they win 70% of their games paying $1.60, we will make money (0.7*1.60 – 1 > 0). In this case, we will want a larger bet on Essendon because they are more likely to win. The optimal amount to bet is not arbitrary – it is calculated using a mathematical formula that optimizes growth in the long-term. So for a team which offer favourable odds, but are still only a small chance to win (imagine a team that is a 10% chance to win, but are paying $20), only needs a small bet. We don’t lose much if they lose, which they probably will, but when they win we will still take a nice profit. So,
Bet less on favourable underdogs, and bet more on favourable favourites.
We calculate the exact amount of money to bet on each game, given their true probability of victory (calculated from our model), and also the bookmaker odds, to maximize long-term profit.
The suggested bet sizes each week are based on a personal pot of $1. Realistically, because you may be placing as many as 9 bets at the same time, you want to only bet a certain fraction of your personal bank. For specific details of a good betting strategy, see the How to Bet section.