$R_{x} \in \{ \ 1 \ , \ 2 \ , \cdots , \ N \ \} $이라고 정의 할 때
$$ x \in \{ \ 1 \ , \ 2 \ , \cdots , \ N \ \} $$
$$ p(x) = \frac{1}{N} $$
$$ F(x) = \frac{x}{N} $$
$$ E(X) = \frac{N+1}{2} $$
$$ Var(X) = \frac{N^{2}-1}{12} $$