高阶多重分形稳定运动:定义与基本性质
Higher-Order Multifractional Stable Motion: Definition and Fundamental Properties
AI总结:
本文提出n阶多重分形稳定运动(n-MFSM),通过L^α可积性分析建立存在性,推导移动平均和调和表示,证明局部渐近自相似性,确定点态Hölder正则性,并刻画长程依赖特征。
摘要:
本文介绍了$n$阶多重分形稳定运动($n$-MFSM),这是一种新颖的随机过程,同时统一了三个关键建模特征:重尾分布($α\in(1,2]$的$α$-稳定分布)、通过函数Hurst参数$H(t)\in(n-1,n)$的时变局部正则性,以及阶数$n\geq1$的扩展标度行为。现有框架无法同时结合这三者。我们通过$L^α$-可积性分析建立了严格的存在性,推导了具有显式常数的移动平均和调和表示,证明了局部渐近自相似性并完全识别了极限过程,确定了精确的点态Hölder正则性$α_X(t)=H(t)-1/α$,并通过余差渐近性刻画了长程依赖。特别地,我们得到了精确的衰减指数$(α-1)H_+ + H(s)-n$和LRD准则$(α-1)H_++H(s)<n$,该准则推广了一阶高斯多重分形过程的经典条件$H(s)+H_+<1$,并在常数$H$的LFSM情形下简化为$αH-1$。
英文摘要:
This paper introduces the $n$-th order multifractional stable motion ($n$-MFSM), a novel stochastic process that simultaneously unifies three key modelling features: heavy-tailed distributions ($α$-stable with $α\in(1,2]$), time-varying local regularity via a functional Hurst parameter $H(t)\in(n-1,n)$, and extended scaling behaviour of order $n\geq1$. No existing framework combines all three. We establish rigorous existence via $L^α$-integrability analysis, derive both moving-average and harmonizable representations with explicit constants, prove local asymptotic self-similarity with complete identification of the limit process, determine the exact pointwise Hölder regularity $α_X(t)=H(t)-1/α$, and characterize long-range dependence through codifference asymptotics. In particular, we obtain the precise decay exponent $(α-1)H_+ + H(s)-n$ and the LRD criterion $(α-1)H_++H(s)<n$, which generalizes the classical condition $H(s)+H_+<1$ for first-order Gaussian multifractional processes and reduces to $αH-1$ for LFSM with constant $H$.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。