The concept of probability has more definition:
- classic probability,
- frequentist probability,
- and subjective probability.
The classic probability is based on the hypothesis that all cases of the event are equally likely. It is define as the ratio between the number of favorable cases and the number of possible cases.
The frequentist probability is based on the hypothesis that the probability of a event is calculated by experiment. It is define as relative frequency as the ratio between the number k of the tests in which the event occurred and the number n of the tests performed.
Then the frequentist probability is define as the limit of relative frequency when the number of the tests tends to infinity.
The subjective probability is define as the probability P(E) of an event E is the measure of the degree of trust that an individual attributes to the occurrence of the event E according, to his knowledge and his opinions.
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