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Multifractal Analysis of Chinese Industry and Stock Markets Fluctuation Under the COVID-19 Pandemic COVID-19 大流行下中国工业和股票市场波动的多分形分析
IF 1.8 4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-11 DOI: 10.1142/s0219477524500135
Pan-Ting Liu, Xin-Bang Cao, Hong-Yong Wang

Researchers and authorities have become increasingly interested in how the COVID-19 pandemic has profoundly impacted the real economy and financial markets around the world since its outbreak in late 2019. Applying the methods of multifractal analysis, this paper investigates the fluctuation characteristics and market risks of Chinese industry and stock markets under the COVID-19 pandemic, and reveals the whole dynamics of industry and stock markets from the perspective of system theory. The empirical results show that the multifractal strength of the industry market has significantly increased during the pandemic with elevated systematic risk, while the situation is different for the stock market. Specifically, the Hurst surfaces generated using the multiscale technique intuitively visualize the dynamical behaviors of the systematic fluctuation of the Chinese industry and stock markets at various scales under the COVID-19 pandemic. Furthermore, it is found that the sources of multifractality of the two types of markets include long-range correlation and fat-tailed distribution, with the contribution of fat-tailed distribution being greater. The chi-square test is promoted in this paper to measure the contribution of the internal components of the multivariate system to the multifractality sources of the whole system, revealing that the real estate industry has a greater impact on the multifractality of the whole industry system, while the Shanghai Composite Index has a stronger influence on the whole stock system.

自2019年底COVID-19大流行爆发以来,研究人员和权威机构越来越关注COVID-19大流行如何深刻影响全球实体经济和金融市场。本文运用多分形分析方法,研究了COVID-19疫情下中国产业和股票市场的波动特征和市场风险,从系统论的角度揭示了产业和股票市场的整体动态。实证结果表明,在大流行病期间,行业市场的多分形强度显著增加,系统性风险上升,而股票市场的情况则不同。具体而言,利用多尺度技术生成的赫斯特曲面直观地展现了 COVID-19 大流行下中国产业市场和股票市场在不同尺度上的系统性波动的动态行为。此外,研究还发现两类市场的多重性来源包括长程相关性和肥尾分布,其中肥尾分布的贡献更大。本文提倡采用卡方检验来衡量多元系统内部成分对整个系统多元性来源的贡献,结果显示,房地产行业对整个行业系统的多元性影响较大,而上证综指对整个股票系统的影响较强。
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引用次数: 0
A Frequency-weighting Digital Filter in Sound Level Meter based on Neural Computing Method 基于神经计算方法的声级计频率加权数字滤波器
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-09 DOI: 10.1142/s021947752450007x
Haiyun Lin, Xinjie Shen, Gang Long, Haijun Lin
Frequency weighting networks are a critical component of a sound level meter (SLM), and their error characteristics directly determine the performances of SLM. For reducing the high-frequency error of the [Formula: see text] frequency-weighting filters with the bilinear transformation method (BTM), a design method for [Formula: see text] frequency-weighting filters based on neural computing method (NCM) is proposed. A detailed algorithm for solving the filter coefficients is provided, and the amplitude-frequency characteristics of the [Formula: see text] frequency-weighting filters with BTM and NCM are compared in detail. The experimental results show that the amplitude-frequency characteristics of the [Formula: see text] frequency-weighting filters in SLM with NCM are significantly better than those of BTM. The filter meets the requirements of the first class SLM defined by IEC61672, which demonstrates the effectiveness of this proposed method.
频率加权网络是声级计的重要组成部分,其误差特性直接决定声级计的性能。为了利用双线性变换方法(BTM)减小[公式:见文]频率加权滤波器的高频误差,提出了一种基于神经计算方法(NCM)的[公式:见文]频率加权滤波器的设计方法。给出了求解滤波器系数的详细算法,并详细比较了采用BTM和NCM的频率加权滤波器的幅频特性。实验结果表明,采用NCM的SLM频率加权滤波器的幅频特性明显优于BTM滤波器。该滤波器满足IEC61672定义的第一类SLM的要求,验证了该方法的有效性。
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引用次数: 0
Parrondo-like behavior in continuous-time random walks with periodically alternating jumps 具有周期性交替跳跃的连续时间随机行走中的类帕隆多行为
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-09 DOI: 10.1142/s021947752450010x
Jiyeon Lee
As a natural generalization of the discrete-time random walk, the continuous-time random walk (CTRW) has been applied to stochastic models with random dynamics in various fields. In this paper, we show that the deterministic alternation of two unbiased CTRWs can lead to a phenomenon similar to the Parrondo paradox, in which the asymptotic mean drift of the combined CTRW becomes positive or negative depending on the parameter values. This extends the case in which the paradox occurs due to the random combination of two CTRWs with memory shown by Montero [Phys. Rev. E 84 (2011) 051139].
连续时间随机漫步(CTRW)作为离散时间随机漫步的一种自然推广,已在各个领域应用于具有随机动力学的随机模型。在本文中,我们证明了两个无偏CTRW的确定性交替可以导致类似于Parrondo悖论的现象,其中组合CTRW的渐近平均漂移随参数值的变化而变为正或负。这就扩展了蒙特罗(Montero)[物理学家]提出的两个ctrw随机组合所导致的悖论。Rev. E 84(2011) 051139]。
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引用次数: 0
IoT Data Visualizations for Hospital Insight in Corporate Finance Utilizing Machine Learning Algorithm 利用机器学习算法实现医院洞察企业财务的物联网数据可视化
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400121
Mengjia Huang, Junjie Wang, Xin Yao, Wenwen Wang, Hui Chen, Zhang Zhiqiang
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引用次数: 0
Enhancing Personalization of Customer Services in E-commerce System using Predictive Analytics 利用预测分析增强电子商务系统客户服务的个性化
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s021947752440011x
Deepshikha Bhargava, Amitabh Bhargava, Romel P Melgarejo-Bolivar, Abigail M. Montes de Oca-Nina, Sushovan Chaudhury
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引用次数: 0
Research on the influence of depth and breadth of equity reform on the performance of state owned enterprises based on Dynamic Panel Data Model 基于动态面板数据模型的股权改革深度和广度对国有企业绩效的影响研究
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400145
Guilin Yang, Guihua Yang, Wanping Yang
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引用次数: 0
Under the Background of Economic Structure Optimization, Environmental Governance Promotes Macroeconomic Structural Adjustment Measures 在经济结构优化背景下,环境治理促进宏观经济结构调整
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400133
Jincai Zhang, Xiangyu Cai
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引用次数: 0
Employing Machine Learning to deduce a causal link between corporate social responsibility and financial performance 利用机器学习来推断企业社会责任和财务绩效之间的因果关系
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400157
Bangwei Rong, Kwen Liew, Mamnoon Rahman
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引用次数: 0
Empirical Analysis of SSE 50 Index Volatility Based on GARCH Model 基于GARCH模型的上证50指数波动率实证分析
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400108
Shiwang Huang, Niukun Liu, Zhichao Wang
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引用次数: 0
Visualization Methods And Empirical Research On Financial Evaluation Of Listed Companies In China 中国上市公司财务评价的可视化方法与实证研究
4区 工程技术 Q3 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS Pub Date : 2023-11-07 DOI: 10.1142/s0219477524400169
Xiaohui Shu, Yangkuo Li, Robert Tian, Fang Yin
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引用次数: 0
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Fluctuation and Noise Letters
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