(1) | \begin{equation} \forall \, j \in J : \mathbb{E} X_j = 0 \end{equation} |
(2) | \begin{equation} \forall \, j \in J : \text{Var} X_j = 1 \end{equation} |
(3) | \begin{equation} \forall \, i, j \in J \left( i \neq j \quad \implies \quad \text{Cov}(X_i, X_j) = 0 \right) \end{equation} |