Definition:Classical Probability Model

Definition
The Classical Probability model is a measure that defines the probability of an event occurring as follows:


 * $\Pr\left(\text{event occuring}\right) := \dfrac {\left( \text {number of outcomes favorable to event}\right)}{\left( \text{total number of outcomes possible}\right)}$

formally:


 * $\Pr\left(\omega\right) := \dfrac {\#\left(\Sigma\right)}{\#\left(\Omega\right)}$

where:


 * $\#$ is the cardinality of a set
 * $\omega$ is an event
 * $\Sigma$ is the event space
 * $\Omega$ is the sample space

This model assumes that all outcomes of the experiment are equally likely. It is particularly useful when analyzing Games of Chance.

Proof that the Classical Probability model is indeed a probability measure is given here.

Also see

 * Classical Probability is a Probability Measure