UNIT ROOT TESTING: A CRITIQUE FROM CHAOS THEORY

A counter-example from chaos theory is used to challenge the augmented Dickey-Fuller (ADF) test and common prewhitening techniques. The ADF test is applied to data constructed from a fully deterministic nonlinear (chaotic) process. The null hypothesis, that a unit root is present, cannot be rejected; “stationarity” is achieved by prewhitening. The largest Lyapunov exponent and the correlation dimension are estimated for the original and conditioned series in efforts to detect the nonlinearity and ascertain information regarding its specification. This is repeated in the presence of additive white noise. In no case is the procedure successful, nor is misspecification avoided. Along the way, the tests for nonlinearity provide evidence in support of the results of Nelson and Plosser (1982), that the removal of deterministic trends from time series that appear to be unit root processes can lead to spurious results.     

金融混沌形成的微观机制分析

金融是现代经济的核心。金融系统的安全、稳定是经济社会稳定发展的关键。金融系统在运行过程中发生因确定性失稳而出现诸如金融市场的剧烈动荡、金融危机等金融混沌现象,给经济的增长与社会的稳定带来了很大的负面影响。从微观方面分析金融混沌的形成机制,研究发现金融混沌的形成主要是由金融市场固有的缺陷、过度的金融创新以及金融监管的缺失三方面因素共同作用的结果。探讨金融混沌的形成机制有助于为防范与控制金融混沌指明方向。     

Detecting Linear and Nonlinear Dependence in Stock Returns: New Methods Derived from Chaos Theory

Interest in the relevance of nonlinear dynamics to fields such as finance and economics has spurred the development of new methods of analysis for time series data. Early tests for chaos led to problems when applied to financial and economic data. This motivated development of the BDS family of statistics to test for nonlinearity generally. More recently, another method of analysis has been introduced into the scientific literature. It uses a test for chaos which is relatively simple and appropriate for financial data. A quantitative version of this test is developed here and is used to analyze stock return data.     

Multivariate long memory structure in the cryptocurrency market: The impact of COVID-19

In this paper, we study the long memory behavior of Bitcoin, Litecoin, Ethereum, Ripple, Monero, and Dash with a focus on the COVID-19 period. Initially, we apply a time-varying Lifting method to estimate the Hurst exponent for each cryptocurrency. Then we test for a change in persistence over time. To model the multivariate connectivity, the wavelet-based multivariate long memory approach proposed by Achard and Gannaz (2016) is implemented. Our results indicate a change in the long-range dependence for the majority of cryptocurrencies, with a noticeable downward trend in persistence after the 2017 bubble and then a dramatic drop after the outbreak of COVID-19. The drop in persistence after COVID-19 is further illustrated by the Fractal connectivity matrix obtained from the Wavelet long-memory model. Our findings provide important implications regarding the evolution of market efficiency in the cryptocurrency market and the associated fractal structure and dynamics of the crypto prices over time.     

互联网金融、股 市场与宏观经济 —基于SVAR模型的实证研究

在加快构建我国多层次资本市场的现实背景下,互联网金融依靠自身的先天优 势,促进资本融通发展迅猛,增强实体经济发展活力,在加快经济结构调整等方面发挥了重要 作用,但也对我国股票市场产生一定冲击。本文分析了我国互联网金融、股票市场与宏观经济 的发展现状以及三者之间相互影响的作用机理,并基于结构VAR模型进行实证研究。研究结果 表明：第一,短期内互联网金融对股票市场产生负向作用,但随着时间的推移负向作用减弱, 并扭负转正。第二,互联网金融对宏观经济产生正向作用。第三,股票市场对宏观经济的冲击 作用较弱,正负效应更迭,以负影响为主。最后,本文基于研究结论给出了相关建议。     

Multiscaling and rough volatility: An empirical investigation

Pricing derivatives goes back to the acclaimed Black and Scholes model. However, such a modelling approach is known not to be able to reproduce some of the financial stylised facts, including the dynamics of volatility. In the mathematical finance community, it has therefore emerged a new paradigm, named rough volatility modelling, that represents the volatility dynamics of financial assets as a fractional Brownian motion with Hurst exponent very small, which indeed produces rough paths. At the same time, prices’ time series have been shown to be multiscaling, characterised by different Hurst scaling exponents. This paper assesses the interplay, if present, between price multiscaling and volatility roughness, defined as the (low) Hurst exponent of the volatility process. In particular, we perform extensive simulation experiments by using one of the leading rough volatility models present in the literature, the rough Bergomi model. A real data analysis is also conducted to test if the rough volatility model reproduces the same relationship. We find that the model can reproduce multiscaling features of the prices’ time series when a low value of the Hurst exponent is used, but it fails to reproduce what the real data says. Indeed, we find that the dependency between prices’ multiscaling and the Hurst exponent of the volatility process is diametrically opposite to what we find in real data, namely a negative interplay between the two.     

俄罗斯政府间财政关系的改革及对我国的启示

近年来俄罗斯对政府间财政关系进行了一系列改革和调整，成功地维护了联邦的统一，促进了经济的复苏和发展。正确处理政府间财政关系也是我国面临的重大课题之一，与我国有相似历史背景、同处于经济转轨时期的俄罗斯在这方面的经验与教训，对我们有更直接的借鉴意义和参考价值。本通过对俄罗斯财政关系现存问题的研究，提出进一步改革与完善的途径和方法，以资我们学习与借鉴。     

The Era of finance: Proposals for the future

Finance, the economic activity intermediating between savings and investments, is probably the first to reach the stage of globalization; as a consequence, the financial sector is taking a leading position in modern economic systems. While the world expects from financial efficiency an increasingly positive contribution to welfare, it appears that recent developments of financial leadership in an increasingly deregulated world system, are also acting negatively on world welfare. In many aspects, it can be established that finance is crisis prone, induces deflationary biases and stimulates speculative behaviour: crisis, deflation and speculation are often harmful to the real economy. A set of proposals are made in order to improve world financial stabilization, promote growth and encourage the spirit of enterprise, as a way of enhancing the future contribution of financial activities to world welfare.     

Geometric Asian options: valuation and calibration with stochastic volatility

The scaling properties of two alternative fractal models recently proposed to characterize the dynamics of stock market prices are compared. The former is the Multifractal Model of Asset Return (MMAR) introduced in 1997 by Mandelbrot, Calvet and Fisher in three companion papers. The latter is the multifractional Brownian motion (mBm), defined in 1995 by Péltier and Lévy Véhel as an extension of the very well-known fractional Brownian motion (fBm).

We argue that, when fitted on financial time series, the partition function as well as the scaling function of the mBm, i.e. of a generally non-multifractal process, behave as those of a genuine multifractal process. The analysis, which concerns the daily closing prices of eight major stock indexes, suggests to evaluate prudently the recent findings about the multifractal behaviour in finance and economics.     

金融支持县域经济发展的思考——以吉林省四平市为例

经济离不开金融,特别是作为我国经济体中弱势地位的县域经济,其发展过程中金融支持发挥着重要的推动作用。对此,本文通过对吉林省四平市县域经济和金融发展现状的调查,深入分析了当前金融支持县域经济发展中存在的若干矛盾和问题,并对如何促进县域经济与金融协调发展提出了建设性建议。     

How does digital inclusive finance affect economic resilience: Evidence from 285 cities in China

Digital inclusive finance can provide effective financial services to consumers and enterprises that are excluded from traditional finance, thereby improving the vitality and resilience of the economy. Using panel data from 285 Chinese cities from 2011 to 2020, this study explores the mechanism of the impact of digital inclusive finance on economic resilience. We also empirically test the direct effect of digital inclusive finance on economic resilience, the moderating effect of the market environment, and the transmission path of mediating variables. The study shows that improving the level of digital inclusive finance has a positive impact on economic resilience, which mainly stems from the deepening of the coverage breadth and use depth of digital inclusive finance and gradually increases over time. In the heterogeneity analysis, we find that the enhanced effect of digital inclusive finance on economic resilience is more significant in the central and eastern regions and in cities with larger economies in China. Further mechanism analysis reveals that the better the financial market environment and business environment are, the stronger the role of digital inclusion finance in promoting economic resilience. In addition, the increase in innovative technology and the growth of the consumption level are two important mediating variables for digital inclusive finance to actively contribute to economic resilience.     

Multiresolution approximation for volatility processes

Abstract

We present an application of wavelet techniques to non-stationary time series with the aim of detecting the dependence structure which is typically found to characterize intraday stock index financial returns. It is particularly important to identify what components truly belong to the underlying volatility process, compared with those features appearing instead as a result of the presence of disturbance processes. The latter may yield misleading inference results when standard financial time series models are adopted. There is no universal agreement on whether long memory really affects financial series, or instead whether it could be that non-stationarity, once detected and accounted for, may allow for more power in detecting the dependence structure and thus suggest more reliable models. Wavelets are still a novel tool in the domain of applications in finance; thus, one goal is to try to show their potential use for signal decomposition and approximation of time-frequency signals. This might suggest a better interpretation of multi-scaling and aggregation effects in high-frequency returns. We show, by using special dictionaries of functions and ad hoc algorithms, that a pre-processing procedure for stock index returns leads to a more accurate identification of dependent and non-stationary features, whose detection results are improved compared with those obtained by other traditional Fourier-based methods. This allows generalized autoregressive conditional heteroscedastic models to be more effective for statistical estimation purposes.     

金融发展与经济动态效率：重庆个案

依据内生经济增长的理论框架,选取重庆市1998年到2016年的相关数据,测算重 庆经济动态效率后发现,2002年前的重庆经济动态效率为正值,经济动态有效。但随着投资驱 动政策的逐年实行,经济动态效率数值由正转为负,进入到动态无效阶段,且下降趋势更为明 显。2009年以后,重庆金融业不断完善,金融对经济的影响效应稳步增强,经济的动态效率又 得到了回升,但仍处于无效状态。实证结果表明重庆金融发展规模、金融运行效率对经济动态 效率有积极的作用,而贷款规模扩大对经济动态效率有负面影响。因此,重庆金融改革应注重 优化金融行业运行结构,降低金融杠杆比例,提高金融运行效率和构建长江上游金融中心,以 提高重庆经济动态效率,并实现金融与经济的内涵式增长。     

双向治理:实体经济与虚拟经济的治本之策

随着实体经济交易需求与产权转换等方面的需要,出现了虚拟经济的范畴.虚拟经济是新经济的一种重要经济形态,作为一把"双刃剑",它给实体经济的发展带来新思想、新变化的同时,也给实体经济的发展带来了种种问题.当今世界,各国实体经济加快发展的过程中,金融自由化和金融深化进程也在不断加快.因此结合实体经济和虚拟经济的问题,改变单向的治理模式是一个迫切的问题.本文从实体经济与虚拟经济问题的联系、从双向治理的角度分析了我国经济实体的优化问题,并提出了相应的政策建议.     

An examination of nonlinear dependence in exchange rates,using recent methods from chaos theory

Interest in the relevance of nonlinear dynamics to finance and economics has spurred the evolution of new ways to analyze time series data. Tests for chaos, based on a metric approach which measures spatial correlations, led to the development of the correlation dimension test for chaos and the BDS test for nonlinearity. More recently, a topological method has been introduced into the scientific literature which employs a simple qualitative test for chaos that is adaptable to the characteristics of financial data. A quantitative version is also presented here. Conflicting evidence exists about the presence of chaotic behavior in exchange-rate data. The qualitative topological test does not support evidence of a chaotic generating mechanism in these series. The quantitative form finds nonlinear dependence and is a useful diagnostic to determine the adequacy of ARCH-type models for this nonlinear structure.     

2004年国际经济金融走势及其对我国经济金融的影响分析

本文对2004年国际经济金融走势进行了较为全面和深入的分析。从全球经济走势来看,世界经济形势持续好转,美日欧以及其他亚洲国家和地区的经济整体表现良好;国际金融市场在全球经济基本面的带动下,总体表现也较为平稳。另外,本文还对2005年的国际经济金融走势进行了预测和分析。同时随着我国改革开放的日益深入,国际经济金融市场的运行对我国经济金融的影响也日益加大。基于此,本文从国际经济金融的大背景出发,分析和预测了其对我国进出口贸易、吸引外资、外汇储备、外债、人民币汇率及在华外资银行和境内外汇存贷款变化等方面的影响。     

实现区域经济和区域金融的互动双赢--促进江苏沿江县域经济发展的金融对策

县域经济是否有活力,是整个国家经济能否蓬勃发展的基础和关键。处于转型期的县域经大多资金基础薄弱,需要金融的支持,而资金的投入就必然伴随着风险。如何坚持科学发展观,实现县域经和县域金融的互动双赢意义重大。本文根据江苏经济发展战略的总体部署,对沿江县域的经济结构、发展点、南北差距及行政架构等方面进行了量化分析,并对沿江县域的金融市场作了全面研判,明确了有所为有所不为的战略思路,指明了金融支持的重点行业和重点领域,创造性地提出了互动发展的资源优化配置架,为沿江县域经济与金融共同繁荣和全面、协调、可持续发展提供了金融对策。     

国际金融危机背景下我国农村金融服务深化路径选择

由美国次贷危机引发的全球金融危机,对世界各国经济社会产生了消极的影响,对我国农业和农村经济的负面影响也逐步显现。本文首先介绍了国际金融危机对我国农村经济与农村金融的影响,其次溯源了农村金融服务的相关理论,并探讨国际金融危机视角下农村金融服务深化的意义,最后针对当前我国农村金融抑制的现状,提出农村金融服务深化的路径选择,以抑制国际金融危机对我国农村经济及农村金融的影响。     

我国各省区市金融发展的经济增长效应分析——基于面板数据的时变趋势与区域特征分析

基于31个省区市1994-2005年的经济金融面板数据的实证分析发现.金融规模扩张、结构优化、效率提升确实有助于促进经济增长,且效率提升比规模扩张更有助于促进地区经济增长.金融发展的经济增长效应存在着区域差异,且受各省区市的地区性基础或禀赋因素的影响较大.随着金融体制改革的推进,各地区金融发展对经济发展的适应性逐步增强,但仍受到金融体制的约束,需要进一步深化改革,加快发展.为此,要充分发挥中央政府主导金融制度供给与创新、地方政府主导当地金融生态建设和市场主导金融资源配置的基础性作用,将统筹区域金融协调发展与部分省区市金融率先发展有机统一起来.     

Does oil price have similar effects on the exchange rates of BRICS?

Motivated by the crucial status of oil price and exchange rates in world finance and economy, we apply daily data from August 2005 to February 2019 to investigate the impact of oil price shocks on the exchange rate of BRICS countries. This paper first adopts a new framework and EEMD method to decompose oil shocks and exchange rate series, respectively. With these econometric methods, the final research variables in this paper are constructed, including two types of oil shocks and three kinds of exchange rate series. The ARDL approach and VAR model are then employed to detect the influence of oil shocks on exchange rates in different frequencies, corresponding to the stationarity of series. The evidence, based on the original exchange rate series reveals that two oil price shocks can produce different effects on net oil-importing countries and net oil-exporting countries, while the results from different frequencies show that exchange rates will have a significant response to oil shocks only at a high frequency. It is worth noting that China is a unique case in BRICS, the relations between its exchange rate and oil price shocks is far insignificant than that of the other countries.