# distribution of order statistic from dependent and independent variables

Consider $X_1$, $X_2$, $X_3$ and $X_4$ are four variables, we know that $X_1$ and $X_4$ are dependent $(X_1 < X_4)$, and $X_2$ and $X_3$ are dependent $(X_2 < X_3)$. Here $X_1$ and $X_2$ are independent, similarly $X_3$ and $X_4$ are independent from each other. Now I want to find the distribution of the $i^{\text{th}}$ order statistic from $(X_1, X_2, X_3, X_4)$. Also note that all (four) variables are non-identically distributed.

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