# Laying by Kelly staking plan

This staking plan is based on so called Kelly Criterion - a method of calculating your stake size based on the size of the bank, the current odds and certain expectations that you have for winning or losing the bet.

The last part is the trickiest. This example is based on the article by The Staking Machine, where there are detailed computations of each component of "the magic formula". I will try to put it in simple words for you, but I expect you to have the page with the article open, so that you could follow me.

So, the strategy assumes that you lay one bet on a specific selection. You can imagine the average number of lucky and unlucky bets you've had lately, and so you can figure out approximately the Strike Rate. The Strike Rate is the percentage of lucky (winning) bets calculated against the recent account history. Say, you placed 100 lay bets, and 80 of them were winning. It means your strike rate is 80%.

Analysing the bets you've been placing, you can tell that the average price of a bet was, say, 4.2. It means you might have laid at a higher or lower price, but if you add up all the prices and divide the sum by the number of bets, you'll get the Average Odds.

It is up to you to choose the time scale on which you will base these calculations. You may look back up to thousands of records, or you may just analyse the last 5 bets. Obviously, the more the better, but even if you have an approximate idea, it will still work for Kelly plan.

These two parameters, Strike Rate and Average Odds are key in the formula for calculating the Expectation. Expectation is a theoretical prediction of the actual probability of winning for the selection you are laying on. Say Expectation is 0.25. It means the odds of selection's winning are 1/0.25 + 1 = 5.0, just like with normal odds calculation.

Having all these parameters in hand, the further lay stake is calculated by the software. There are some additional settings to this plan, such as Divisor, which allows you to regulate the percentage of the bank you want to bet. The greater is the Divisor, the less will be the stake (and less risk). Also, bets are based on the current size of the bank, i.e. the available funds. But you may change this to a fixed number, so that for instance the bet will always be a percentage of £50.

There are numerous triggers in the file, but it is advised that you change only the triggers and constants with the following names:

• setting divisor. Change the value of the trigger to a bigger number if you want to reduce the size of each bet.
• setting strike rate. Change the value of the trigger to set your own strike rate. Attention! Strike rate is different for each strategy. You should analyse your account statement in order to find the optimal value. The easiest way is to count winning bets and divide them by the total number of bets. Then multiply it by 100, and you will get the strike rate in %. Please note! The less is your strike rate, the smaller should be the odds of the selections you are laying on. If you have low strike rate and high average odds, most probably the bet will not be placed, as the expectation will be negative.
• setting average odds. This is another parameter you will have to work out from your account statement. Set this value to the average odds of your lay bets. For those who are being lazy, this trigger file contains two triggers that calculate the average odds of the last 10 bets taken from your betting history. You can deactivate these triggers if they are not needed. Their names are "optional setting avg odds" and "optional setting history depth".
• setting the base for the bet. By default the base will be equal to the available funds, but you may change this value if you want bets to be calculated based on a different amount of money.

Discuss this trigger example on our forum.

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