Bookmakers employ complex algorithms to set odds, but they are not infallible. Furthermore, they adjust odds based on public sentiment (where the money is going) rather than just pure probability. By inputting statistical data into your Excel model, you can calculate your own "fair odds." If your analysis suggests a team has a 50% chance of winning, the fair odds are 2.00. If the bookmaker offers 2.20, you have found a "Value Bet." An Excel sheet automates this comparison.