To begin with all sport is effected by the 'law of averages', the law of averages is basically a thousand year phenomenon that believes any event occurring again and again will eventually fail. For example, the law of averages believes a horse winning 3 races in row is likely to lose the 4th and the chances of failure increase with every subsequent victory. All betting systems today incorporate the law of averages in their calculations. One of the most popular betting systems today are horse racing systems. Like most scientific methods, horse racing systems take into account a horse's past performance, its current form, and then calculate the probability of the horse winning. In addition a horse racing system also incorporates the performance of competing horses.
It is now up to the person placing the bet to choose which horse to bet on. Some systems also produce the most likely winner instead of the probability of each individual horse winning. A newer, 21st century horse racing system is Go Fibonacci - the system uses a complex mathematical system developed by the greatest mathematician of all time Fibonacci.
It is important to remember that horse racing systems are not 100% fool proof, and nothing on the planet can predict the outcome of a sporting event (unless it has been rigged). However, you can limit the risk through maths. All racings systems do is use mathematics to produce a probable winner (or in this case, loser). This system is recommended for those who do not want to risk too much whilst still make a good amount of profit from their betting.