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Jiehua Xie

Publications and source records attributed to Jiehua Xie.

3 recordsLinked to original sources

Quasi-copulas with a prescribed sub-track section

In this paper, we consider the quasi-copulas and copulas with a prescribed sub-track section, i.e., with given values along the curve segment connecting the points (x0,0) and (1,1-x0) for 0<x0<1. By employing the technique based on the W-ordinal sum, we provide methods for constructing quasi-copulas and copulas whose sub-track section coincides with a given one. Then, we further investigate construction methods for symmetric quasi-copulas and copulas with a prescribed sub-track section. Furthermore, we determine the best-possible bounds for the class of quasi-copulas sharing a common sub-track section, and verify that the lower bound obtained is also the best-possible lower bound for the class of copulas with a common sub-track section. Finally, we examine several properties of the bound (quasi-)copulas with a prescribed sub-track section, including their comparison with bound (quasi-)copulas with a given track section or a sub-diagonal section, as well as their statistical characteristic and concordance order.

math.PR↗

Asymptotic fractional-order stochastic dominance with bounded relative risk aversion

In this paper, we propose a novel asymptotic fractional-order stochastic dominance rule for ranking prospects over a sufficiently long investment horizon. The new rule formulates the consensus of decision makers whose relative risk aversion has a negative lower bound. Under the assumption that returns are lognormally distributed, we establish equivalent conditions for the proposed rule without imposing the non-negativity constraint on the mean of log-return, a restriction usually required by the existing asymptotic stochastic dominance rules. Furthermore, to enhance the tractability of this asymptotic fractional-order stochastic dominance, we propose a variant of asymptotic fractional-order stochastic dominance with bounded relative risk aversion, referred to as general asymptotic fractional-order stochastic dominance, under an additional condition on decision makers' marginal utilities. We derive its corresponding equivalent distributional characterizations. The (general) asymptotic fractional-order stochastic dominance with bounded relative risk aversion overcomes the shortcomings of the existing asymptotic fractional-order criterion that the fractional-order parameter has no influence on the equivalent distributional conditions. Empirical examples further show the advantages of the newly proposed rules for asset selection in long-term investment decisions.

q-fin.RM↗

A family of transformed copulas with singular component

In this paper, we present a family of bivariate copulas by transforming a given copula function with two increasing functions, named as transformed copula. One distinctive characteristic of the transformed copula is its singular component along the main diagonal. Conditions guaranteeing the transformed function to be a copula function are provided, and several classes of the transformed copulas are given. The singular component along the main diagonal of the transformed copula is verified, and the tail dependence coefficients of the transformed copulas are obtained. Finally, some properties of the transformed copula are discussed, such as the totally positive of order 2 and the concordance order.

math.ST↗