Definition:Equiprobable Outcomes

Let $$\left({\Omega, \Sigma, \Pr}\right)$$ be a finite probability space.

Let $$\Omega = \left\{{\omega_1, \omega_1, \ldots, \omega_n}\right\}$$.

Suppose that $$\Pr \left({\omega_i}\right) = \Pr \left({\omega_j}\right)$$ for all the $$\omega_i, \omega_j \in \Omega$$.

Then from Probability Mass Function on Equiprobable Outcomes:
 * $$\forall \omega \in \Omega: \Pr \left({\omega}\right) = \frac 1 n$$
 * $$\forall A \subseteq \Omega: \Pr \left({A}\right) = \frac {\left|{A}\right|} n$$

Such a probability space is said to have equiprobable outcomes, and is sometimes referred to as an equiprobability space.