## Setting Odds

You are automatically setting up the Odds percentage of win/lose when you type in the number allotted for each prize by the number of players. A simple Odds example is if you have 10 people playing with 5 Winners and 5 Losers, the odds of winning is 1 out of 2.

A second example is if you have 205 players with a game set to 200 losers and 5 winners, then the Odds of winning will be low and slow.

### Number of Players

Another issue to consider when setting the Odds is there is a probability that everyone you project is going to play does not. Out of the 205 players, 50 may only play the first few days, and they could all be losers.

In this case, I would put Losers on “Pause” for a few hours and keep Winners “Activated” on the number of Winners increase, especially if everyone knows each other, like if the players are employees of one company.

Winners will brag to other teammates they won, which is a great buzz to get people excited and play if they haven’t already.

### Watch Winners and Losers Closely.

We recommend that you watch your game Winners and Losers daily and make any adjustments to each Winner and Loser prizes’ quantity set.

If you have a game with more Losers than Winners and see the number of Losers far out-pacing winners, lower the number allocated to “Losers” so things even-out more for a better mix of Winners Losers.

### The Right Blend

Having the right blend of Winner and Losers will keep players pumped-up that they have a chance of winning something.

The other thing is only you know what is going on, not the individual players, unless they are all in daily contact with each other.

If you posted Winners and Losers’ names on a leaderboard, social networks, or your website, this would have a significant impact.

### Monitor Game Results

Monitoring the win/lose percentage on virtual scratchers will ensure your scratch-off campaign’s success.

Article

**How Professionals Set the Odds.**

Here we’ll take a more in-depth look at the nuts and bolts of setting odds, including the mathematics used to convert probabilities into the odds.

Partial Reprint – by BetHQ.com

**The basic principle of probability.**

A basic principle in betting is that for any market, the probabilities of all possible outcomes can be added to give exactly 100%.

The easiest way to illustrate how this principle works in practice is using the example of tossing a coin. If a coin is tossed, there’s a 100% chance that the coin will land on either heads or tails. It has to land on one of its two sides.

Provided the coin is tossed enough times, there’s a 50% probability that it will land on heads and a 50% probability it will land on tails. Each of the two possibilities together equals 100%.

**How probabilities relate to odds.**

Let’s take the probability of 50%. If you convert 50% into a whole number, it becomes 0.5. You can also write this as 1/2. If calculating odds were as simple as converting a percentage into a fraction, the coin toss’s odds market would be 1/2 for heads and 1/2 for tails. This would mean that you’d make a profit equal to half of your stake if you bet on one of these outcomes.

If you bet £1 on heads, for instance, and your bet wins, you’d be paid back your stake plus 50 pence. If you bet £1 on both of the outcomes for a single coin toss, you’d end up losing 50 pence no matter how the coin landed. This is because you’d earn a profit of 50 pence for the winning bet but lose your stake of £1 for the losing bet.

In betting markets, nobody would be satisfied with losing 25% of their funds even if they covered two equally likely but opposing options. Instead, punters would expect to get their overall stake back. As a result, you can’t simply convert probability percentages directly into odds. They have to be calculated using a different method.

**Relative probability.**

A special formula is used to convert probabilities into odds. The formula is as follows:

*Odds of a/b = relative probability of b/(a+b)*

In the formula, a/b is the bookmaker odds, and b/(a+b) is the relative probability of a particular outcome.

Consider the example of tossing a coin. The real probability for each outcome is 1/2. So you can rewrite the formula as b/(a+b)=1/2.

Using algebra, you can calculate the values of a and b in the formula as follows:

- b/(a+b)=1/2
- b = a+b x 1/2
- 2b=a+b
- b=a

If b is 1, a is also 1. Accordingly, the real probability of 1/2 results in odds of 1/1. With odds of 1/1 for heads and 1/1 for tails, a punter who bets £1 on both markets is guaranteed to earn back the whole stake. This person will earn a profit of £1 for the winning bet and lose the stake of £1 on the losing bet. This means the market and payouts perfectly reflect the statistical probability of any one of the two events occurring.

**Converting odds into probability.**

You can convert the odds that bookies publish into probability values to approximate how the bookies’ rate outcomes.

For example, consider a football match in which one team is priced 2/1 to win. Using the formula from above, where odds of a/b represent a relative probability of b/(a+b), you can determine that odds of 2/1 = 1/(2+1), or 1/3 So the odds indicate the belief that there’s a 1/3, or 33%, probability of the team winning the match.

If you try to calculate all of the odds for a football market at a bookmaker, you’ll discover something interesting. We can demonstrate this with a real example of a football match market. Here’s a betting market from Paddy Power for a match between Everton and Chelsea. In this market, we can see that:

Everton is priced at 12/5

the draw is priced at 9/4

Chelsea is priced at 6/5.

Using the formula, the probability for each of these outcomes is as follows:

Everton: 29%

Draw: 30.7%

Chelsea: 45.5%

Adding these probabilities gives 105.2%. This appears to contradict the principle that adding all possible outcomes’ principles must give 100%. This is for a simple reason. Bookmakers don’t publish true odds; instead, they lower the odds they publish to ensure that they profit. The difference between the true odds and the published odds is called the overround.

**How the overround affects odds.**

A bookmaker might set odds of 9/10 for each possible outcome of a coin toss. Note that using the formula from above equates to a probability of 52.6% for each outcome – giving a total of 105.2%. The overround in this example is 5.2%. This is the bookmaker’s profit margin. It ensures that the amount of money collected from losing bets exceeds the amount paid out in winning bets over the long term.

Using the coin toss as an example, say a bookmaker decides to apply an overround of 10% to the market. This would mean that the combined market would need to have a probability of 110%. The coin toss probabilities are therefore as follows:

heads: 55%

tails: 55%.

Using the odds conversion formula, we find that this produces odds of:

heads: 8/10

tails: 8/10.

Now say you bet £1 on each of the two possible outcomes. You’ll forfeit £1 on the losing bet and win 80 pence on the winning bet, giving you a total return of £1.80. This means you will have lost 20 pence on the transaction – which is exactly 10% of the combined bet. This is the 10% overround.