Stochastic Comparisons of Series and Parallel Systems with Independent and Heterogeneous Log-Logistic Components

Document Type : Original Paper


1 Department of Statistics, , Razi University, Kermanshah, Iran.

2 Department of Statistics, Zabol University. Iran

3 Department of Statistics, Razi University, Kermanshah, Iran.


This paper examines the problem of  stochastic comparisons of  series and parallel systems with independent  and heterogeneous  Log-logistic components.  Using concepts of majorizatin, weak supermajorization and p-larger order, we establish usual stocahastic order, hazard rate and reversed hazard rate order between these systems. We also discuss the stochastic comparisons of two vector of order statistics arising from two independent and hetrogeneous Log-logestic samples.


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