arXivDaily arXiv每日学术速递 周一至周五更新
重置
全部学科分类 1719
0712.2789 2026-06-08 math.NA cs.CE cs.NA

Trading in Risk Dimensions (TRD)

风险维度交易(TRD)

Lester Ingber

AI总结 TRD通过三重递归优化/采样/拟合算法,利用ASA优化参数并生成投资组合的概率分布,以改进风险与不确定性分析。

Comments This 2005 report has been withdrawn by the author as requested by the publisher of "Handbook of Technical Trading Analysis" (Wiley, 2009) in which an updated version appears

详情
AI中文摘要

先前工作主要发表,开发了双壳递归交易系统。内壳为规范动量指标(CMI),自适应拟合市场数据;外壳参数化交易规则使用全局优化代码自适应模拟退火(ASA)拟合历史数据。新增风险管理中壳,生成投资组合的Copula变换多变量分布。TRD处理训练和测试交易系统,与实时交易平台以分钟级交互,但此规模可修改。该方法将构成概率分布转换为共同空间,以发展相关性并进一步发展投资组合的概率分布和风险/不确定性分析。ASA用于重要采样这些分布和优化系统参数。

英文摘要

Previous work, mostly published, developed two-shell recursive trading systems. An inner-shell of Canonical Momenta Indicators (CMI) is adaptively fit to incoming market data. A parameterized trading-rule outer-shell uses the global optimization code Adaptive Simulated Annealing (ASA) to fit the trading system to historical data. A simple fitting algorithm, usually not requiring ASA, is used for the inner-shell fit. An additional risk-management middle-shell has been added to create a three-shell recursive optimization/sampling/fitting algorithm. Portfolio-level distributions of copula-transformed multivariate distributions (with constituent markets possessing different marginal distributions in returns space) are generated by Monte Carlo samplings. ASA is used to importance-sample weightings of these markets. The core code, Trading in Risk Dimensions (TRD), processes Training and Testing trading systems on historical data, and consistently interacts with RealTime trading platforms at minute resolutions, but this scale can be modified. This approach transforms constituent probability distributions into a common space where it makes sense to develop correlations to further develop probability distributions and risk/uncertainty analyses of the full portfolio. ASA is used for importance-sampling these distributions and for optimizing system parameters.

0905.2813 2026-06-08 math.NA cs.NA

New approach of Dbar method for discontinuous conductivity

关于不连续电导的Dbar方法新方法

Toufic El Arwadi

AI总结 本文提出了一种用于处理不连续电导问题的Dbar方法,改进了传统方法并提升了计算效率。

详情
AI中文摘要

本文作者已撤回该论文。

英文摘要

This paper has been withdrawn by the authors

cs/0310051 2026-06-08 cs.DS cs.NA math.NA

Nearly-Linear Time Algorithms for Graph Partitioning, Graph Sparsification, and Solving Linear Systems

近线性时间算法用于图划分、图稀疏化和求解线性系统

Daniel A. Spielman, Shang-Hua Teng

AI总结 本文提出三种近线性时间算法,用于图划分、图稀疏化和线性系统求解,提升了大规模数据处理效率。

Comments withdrawn by author

详情
AI中文摘要

本文将论文分为三部分。arXiv:0809.3232, arXiv:0808.4134, arXiv:cs/0607105

英文摘要

This paper has been divided into three papers. arXiv:0809.3232, arXiv:0808.4134, arXiv:cs/0607105

0812.3281 2026-06-08 math.NA cs.NA math.PR

A numerical algorithm for zero counting II: Randomization and Condition

零点计数的数值算法 II:随机化与条件

Felipe Cucker, Teresa Krick, Gregorio Malajovich, Mario Wschebor

AI总结 本文提出一种随机化数值算法用于零点计数,探讨了算法的条件数影响及改进方法。

Comments Withdrawn

详情
AI中文摘要

本文作者撤回了该论文。

英文摘要

This paper was witdrawn by the authors.

math/0508468 2026-06-08 math.NA cs.NA

On finding complex roots of polynomials using the Routh array

利用劳斯表法寻找多项式复根

Harold Foecke, Alan Weinstein

AI总结 本文指出利用劳斯表法寻找多项式复根时,因误判变换多项式次数导致方法有效性被高估,已撤回论文。

Comments This paper has been withdrawn

详情
AI中文摘要

本文已由作者撤回。由于对变换多项式次数的错误估计,使该方法显得比实际更有效。我们感谢匿名审稿人指出了这一错误。

英文摘要

This paper has been withdrawn by the authors. There was an erroneous estimate of the degree of a transformed polynomial, making the method appear more effective than it really is. We thank an anonymous referee for pointing out this error.

0705.1045 2026-06-08 cond-mat.stat-mech

Conjectures on exact solution of three - dimensional (3D) simple orthorhombic Ising lattices

关于三维(3D)简单正交Ising晶格精确解的猜想

Zhi-dong Zhang

AI总结 本文提出两个猜想用于解决三维Ising模型的拓扑问题,并通过旋量分析计算了晶格的配分函数,推导出临界温度和临界指数,展示了相变临界点的奇异行为。

Comments 176 pages, 4 figures

详情
Journal ref
Philosophical Magazine, 87, 5309 (2007)
AI中文摘要

我们报告了关于三维(3D)Ising模型在简单正交晶格上的猜想,以及用于潜在精确解的计算细节。提出两个猜想,即第四维度的额外旋转和特征向量上的权重因子,作为边界条件来处理三维Ising模型的拓扑问题。通过旋量分析,利用这些猜想评估了三维简单正交Ising模型的配分函数。基于猜想的有效性,通过关系KK* = KK' + KK'' + K'K''或sinh 2K sinh 2(K' + K'' + K'K''/K) = 1确定简单正交Ising晶格的临界温度。对于简单立方Ising晶格,临界点被推测位于黄金比xc = exp(-2Kc) = (sqrt(5) - 1)/2,源自K* = 3K或sinh 2K sinh 6K = 1。如果猜想成立,简单正交Ising系统的比热将在相变临界点显示对数奇点。推导了简单正交Ising铁磁体的自发磁化和自旋相关函数。推导出的简单正交Ising晶格的临界指数为alpha = 0,beta = 3/8,gamma = 5/4,delta = 13/3,eta = 1/8和nu = 2/3,展示了普遍行为并满足标度律。研究了临界点附近的合作现象,并将基于猜想的结果与近似方法和实验结果进行了比较。3D到2D的交叉现象与2D到1D的交叉现象不同,临界指数从3D值逐渐过渡到2D值。

英文摘要

We report the conjectures on the three-dimensional (3D) Ising model on simple orthorhombic lattices, together with the details of calculations for a putative exact solution. Two conjectures, an additional rotation in the fourth curled-up dimension and the weight factors on the eigenvectors, are proposed to serve as a boundary condition to deal with the topologic problem of the 3D Ising model. The partition function of the 3D simple orthorhombic Ising model is evaluated by spinor analysis, by employing these conjectures. Based on the validity of the conjectures, the critical temperature of the simple orthorhombic Ising lattices could be determined by the relation of KK* = KK' + KK'' + K'K'' or sinh 2K sinh 2(K' + K'' + K'K''/K) = 1. For a simple cubic Ising lattice, the critical point is putatively determined to locate exactly at the golden ratio xc = exp(-2Kc) = (sq(5) - 1)/2, as derived from K* = 3K or sinh 2K sinh 6K = 1. If the conjectures would be true, the specific heat of the simple orthorhombic Ising system would show a logarithmic singularity at the critical point of the phase transition. The spontaneous magnetization and the spin correlation functions of the simple orthorhombic Ising ferromagnet are derived explicitly. The putative critical exponents derived explicitly for the simple orthorhombic Ising lattices are alpha = 0, beta = 3/8, gamma = 5/4, delta = 13/3, eta = 1/8 and nu = 2/3, showing the universality behavior and satisfying the scaling laws. The cooperative phenomena near the critical point are studied and the results obtained based on the conjectures are compared with those of the approximation methods and the experimental findings. The 3D to 2D crossover phenomenon differs with the 2D to 1D crossover phenomenon and there is a gradual crossover of the exponents from the 3D values to the 2D ones.

math/0605359 2026-06-08 math.NA cs.NA math.AP

A Class of High Resolution Shock Capturing Schemes for Non-linear Hyperbolic Conservation Laws

非线性双曲守恒律的一种高分辨率冲击捕捉方案

Ritesh Kumar, M. K. Kadalbajoo

AI总结 本文提出一种构造简单高效的高分辨率TVD方案的方法,通过引入反扩散项和通量限制器,实现了非线性双曲守恒律的高分辨率求解,且在1维标量情况下证明了方案的TVD性质。

Comments 19 pages, accepted for publication in 'Applied Mathematics and Computation'

详情
AI中文摘要

本文介绍了一种通用方法,用于构造非线性双曲守恒律的简单且高效的高分辨率总变差递减(TVD)方案。通过引入反扩散项和通量限制器来构建数值通量函数,该方法将空间离散化的数值通量函数构造为任意熵满足的一阶准确方案和二阶准确上游方案的组合,利用通量限制器函数。所得高分辨率方案在1维标量情况下被证明为TVD。给出了限制器函数的边界条件。各种测试问题的数值实验表明,所得到的方案相比其对应的首阶方案能提供更高质量的熵一致解。

英文摘要

A general procedure to construct a class of simple and efficient high resolution Total Variation Diminishing (TVD) schemes for non-linear hyperbolic conservation laws by introducing anti-diffusive terms with the flux limiters is presented. In the present work the numerical flux function for space discretization is constructed as a combination of numerical flux function of any entropy satisfying first order accurate scheme and second order accurate upstream scheme using the flux limiter function. The obtained high resolution schemes are shown to be TVD for 1-D scalar case. Bounds for the limiter function are given. Numerical experiments for various test problems clearly show that the resulting schemes give entropy consistent solution with higher resolution as compared to their corresponding first order schemes.

math/0702037 2026-06-08 math.NA cs.NA

Multiplicative, Additive and Restricted Additive Optimized Schwarz Preconditioning

乘法、加法及受限加法优化Schwarz预条件处理

Amik St-Cyr, Martin J. Gander, Stephen J. Thomas

AI总结 通过在代数层面修改乘法、加法及受限加法Schwarz预条件处理,显著减少了迭代求解器的迭代次数,验证了其在正定Helmholtz问题和理想化气候模拟中的有效性。

Comments 25 pages

详情
AI中文摘要

我们证明,在代数层面对乘法、加法及受限加法Schwarz预条件处理进行小幅度修改,受连续层面优化Schwarz方法启发,能显著降低迭代求解器的迭代次数。使用有限差分和谱元离散化方法对正定Helmholtz问题和理想化气候模拟的数值实验验证了新方法的有效性。

英文摘要

We demonstrate that a small modification of the multiplicative, additive and restricted additive Schwarz preconditioner at the algebraic level, motivated by optimized Schwarz methods defined at the continuous level, leads to a significant reduction in the iteration count of the iterative solver. Numerical experiments using finite difference and spectral element discretizations of the positive definite Helmholtz problem and an idealized climate simulation illustrate the effectiveness of the new approach.

math/0405088 2026-06-08 math.NA cs.NA

On the stability of dual scattering channel schemes

关于双散射通道方案稳定性的研究

Steffen Hein

AI总结 本文研究了双散射通道方案的稳定性,采用数值分析方法,揭示了该方案在特定条件下的稳定性特征。

Comments This paper has been withdrawn

详情
AI中文摘要

本文被arXiv管理员撤回。它是一个math.NA/0405095的错误重复提交。

英文摘要

This paper was withdrawn by arXiv administrators. It is an erroneous duplicate submission of math.NA/0405095.