| Decimal | American | Probability |
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A professional better should be well-versed in the coefficients, quickly and correctly assess the probability of an event by the coefficient, and if necessary be able to transfer the coefficients from one format to another. In this manual, we will talk about what types of coefficients are, and we will also analyze how to calculate the probability from a known coefficient and vice versa.
What are the types of odds?
There are three main types of odds that bookmakers offer players: decimal odds, fractional odds (English) and American odds. The most common odds in Europe are decimal. American odds are popular in North America. Fractional coefficients are the most traditional form, they immediately reflect information about how much you need to put in order to get a certain amount.
American odds
These types of odds are popular in North America. At first glance, they seem rather complicated and incomprehensible, but do not be scared. Understanding American odds can be useful, for example, when playing in American casinos, to understand the quotes displayed in North American sports broadcasts. Let’s figure out how to assess the probability of an outcome based on US odds.
First of all, you need to understand that American odds are positive and negative. A negative US coefficient always goes in the format, for example, “-150”. This means that in order to get $ 100 in net profit (winnings), you need to bet $ 150.
A positive US ratio is calculated the other way around. For example, we have a coefficient of “+120”. This means that in order to get $ 120 in net profit (winnings), you need to bet $ 100.
Now let’s look at how to calculate the probability of an outcome based on positive and negative US odds. Let’s start with the negative ones.
The probability calculation based on negative US coefficients is done according to the following formula:
(- (negative American coefficient)) / ((- (negative American coefficient)) + 100)
or:
(- (- 150)) / ((- (- 150)) + 100) = 150 / (150 + 100) = 150/250 = 0.6
That is, the probability of an event for which a negative US coefficient of “-150” is given is 60%.
Now consider similar calculations for a positive US coefficient. The probability, in this case, is calculated by the following formula:
100 / (positive US ratio + 100)
or
100 / (120 + 100) = 100/220 = 0.45
That is, the probability of an event for which a positive American coefficient of “+120” is given is 45%.
Decimal odds
Decimal odds when multiplied by the size of the bet allow you to calculate the entire amount that you will receive on hand in case of a win. For example, if you bet $ 1 on a coefficient of 1.80, in case of a win you will receive $ 1,80 (1 dollar – the returned bet amount, 0.80 – winning the bet, it’s your net profit).
In order to calculate the probability of an event based on a decimal coefficient, it is necessary to carry out simple calculations – divide the unit by a coefficient. For the above ratio of 1.80, the calculation will be as follows:
1 / 1.80 = 0.55
That is, the probability of an outcome, according to bookmakers, is 55%.
Fractional odds
Fractional coefficients are the most traditional form of coefficients. The numerator shows the potential amount of net gain. In the denominator is the amount of the bet that needs to be made in order to get this same win. For example, a coefficient of 7/2 means that in order to get a net win of $ 7, you need to bet $ 2.
In order to calculate the probability of an event based on a decimal coefficient, simple calculations should be carried out – divide the denominator by the sum of the numerator and denominator. For the aforementioned coefficient 7/2, the calculation will be as follows:
2 / (7 + 2) = 2/9 = 0.22
That is, the probability of an outcome, according to bookmakers, is 22%.
How to convert the coefficient to another format?
There are cases when it is necessary to transfer the coefficients from one format to another. For example, we have a fractional coefficient 3/2 and we need to convert it to decimal. To convert a fractional coefficient to decimal, we first determine the probability of an event with a fractional coefficient and then translate this probability into a decimal coefficient.
The probability of an event with a fractional coefficient of 3/2 is 40%.
2 / (3 + 2) = 2/5 = 0.4 = 40%;
Now we will translate the probability of the event into a decimal coefficient, for this 100 we divide by the probability of the event in a percent:
100/40% = 2.5;
Thus, the fractional coefficient 3/2 is equal to the decimal coefficient 2.5. Similarly, for example, American coefficients are converted to fractional, decimal to American, etc. The most difficult part of all this is just the calculations.