In this paper, we investigate some multivariate integral stochastic orderings of skew-normal random vectors. We derive the results of the sufficient and/or necessary conditions by applying an identity for $ Ef({\mathbf Y})-Ef({\mathbf X}) $, where $ {\mathbf X} $ and $ {\mathbf Y} $ are multivariate skew-normal random vectors, $ f $ satisfies some weak regularity condition. The integral orders considered here are the componentwise convex, copositive, completely-positive orderings and their corresponding increasing ones as well as linear forms of stochastic orderings, which play a vital role in transforming the unmanageable multivariate components into an easy-to-handle univariate variable.
Citation: Xueyan Li, Chuancun Yin. Some stochastic orderings of multivariate skew-normal random vectors[J]. AIMS Mathematics, 2023, 8(10): 23427-23441. doi: 10.3934/math.20231190
In this paper, we investigate some multivariate integral stochastic orderings of skew-normal random vectors. We derive the results of the sufficient and/or necessary conditions by applying an identity for $ Ef({\mathbf Y})-Ef({\mathbf X}) $, where $ {\mathbf X} $ and $ {\mathbf Y} $ are multivariate skew-normal random vectors, $ f $ satisfies some weak regularity condition. The integral orders considered here are the componentwise convex, copositive, completely-positive orderings and their corresponding increasing ones as well as linear forms of stochastic orderings, which play a vital role in transforming the unmanageable multivariate components into an easy-to-handle univariate variable.
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