What is the classical probability model?

The classical definition of probability is classical probability.

Classical probability, also known as prior probability, means that when all possible results and their frequency in random events can be known by deduction or extrapolation, the probability of all possible results can be calculated without any statistical test.

Classical probability is based on the assumption that the events that random phenomena can occur are limited and incompatible, and the possibility of each basic event is equal.

For example, when throwing a flat coin, heads up and tails up are the only two possible basic events, and they are incompatible with each other. If the positive event is recorded as e and the probability of event e is recorded as p(E), then:

p(E)= 1/( 1+ 1)= 1/2

Generally speaking, if there is a basic event A that constitutes event A and a B event that does not constitute event A within all possible basic events, the probability of occurrence of event A is:

P(A)=a/(a+b)