In Betfair, players determine how much the odds are worth through the interaction between those who place back bets and those who place lay bets, unlike what happens in a bookmaker. This means that the value of the odds in the market depends on how much money is placed on back and lay bets for each possible outcome. Therefore, the balance of the markets depends on this interaction.
The market is balanced when the amount to be matched on each side is the same, that is, when the amount placed on back bets is similar to that placed on lay bets. However, sometimes, these markets are off balance and need to be adjusted by changing the odds. This happens in two cases:
1 - If there are more back bets waiting to be matched than lay bets (more money applied in back bets than in lay bets), the odd will tend to decrease, as an adjustment. In this case, the Weight of Money is pushing the odds down;
2- Similarly, if there are more lay bets waiting to be matched than back bets (more money applied in lay bets than in back bets), the odd will tend to increase in order to adjust the market. The weight of money pulls the odds up;
When a market is off balance, the odds change. This change can be anticipated whenever the Weight of Money pushes the odds of one selection in a certain direction (up, for example) and, at the same time, pushes the odds of the remaining selections in the opposite direction (down, for example).
The following example taken from the trading and betting software Traderline, shows an analysis of the weight of money:
Traderline shows WOM (Weight Of Money) as a percentage, making it easy to see when the market is balanced or off balance:
• Whenever the percentage shown is less than 50%, the amount of money waiting to be matched in lay bets is higher than the amount of money waiting to be matched with back bets.
• Similarly, whenever the WOM is more than 50%, the amount of money waiting to be matched in back bets is higher than the amount of money waiting to be matched with lay bets.
By comparing the percentage of the weight of money for each selection, it is possible to predict how the odds of the market will vary.
For a selection of Betting Apps for Betfair.com please see the Betfair App Directory