Fixed-odds betting – Wikipedia

It is habitual with fixed-odds gaming to be aware of the odds at the time of their position of the wager (the“live price“), but the category also includes wagers whose price is determined only when the race or game begins (the“beginning prices“). It’s ideal for bookmakers to price/mark a book like the net result will be in their favor: the sum of the probabilities quoted for all possible outcomes are going to be in excess of 100%. The surplus over 100% (or even overround) signifies profit to the bookmaker in the event of a balanced/even book. In the usual case of an book, the bookmaker may need to pay out more winnings than what is staked or might bring in greater than mathematically. An imbalanced book may emerge because there’s absolutely no way for a bookmaker to know the true probabilities for the results of contests left to human work or to forecast the stakes that will be drawn from others by fixed odds compiled predicated on personal view and comprehension.
With the arrival of Internet and bet exchange betting, Dutch novels against bookmakers and exchanges and the chance of fixed-odds arbitrage actions has enlarged significantly. Betting exchanges in particular act like a stock exchange, allowing the odds to be put in the plan of trading between individual bettors, usually resulting in lent odds that are reasonably near the“true chances.“

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