有关分形市场假说的理论认识

本文简要介绍了分形市场假说的理论背景,对比了有效市场假说和分形市场假说的区别与联系.在回顾了国内外对于分形市场假说的相关研究成果后,发现实证研究成果表明分形市场假说在全世界范围的各个资本市场内均成立.但目前为止还未有基于分形市场假说发展的资产定价工具.这也是未来进一步研究的重点.     

分形市场假说与股票市场的有效性分析

主流的金融计量理论是以价格的随机游走和收益的正态分布假设为基础的,而分形市场研究认为价格是分形,价格遵循有偏随机游走,并用分形分布描述收益的分布规律;在分形研究的框架下,作为主流有效市场假说的替代理论,分形市场假说用不同投资期水平下的投资者对信息的不同评估来解释价格行为的分形机制,也启发我们从动态的和相对的角度去思考股票市场的有效性问题。     

三种资本市场假说介评

西方金融投资学的主流观点是以有效市场假说为基础 ,以均衡、线性思维、标准计量模型优化求解为主要特征的。它们受到广泛的实证检验,是现代资本市场理论的基石。协同市场假说尤其是分形市场假说等新的更为广义的非线性理论的出现 ,为资本市场研究和投资策略设计开创了一种新视角和新方法 ,并可能重新构造资本市场理论框架     

分形市场假说对现代金融学线性范式的挑战——分形市场假说文献述评

现代金融学采用线性范式建立起了完整的理论体系。非线性科学的发展表明线性范式的局限性正是导致现代金融学陷入困境的重要原因。分形市场假说基于非线性范式，采用有限理性人假设和演进的研究方法，对金融市场做出了迥异于有效市场假说的解释。其代表的非线性的思维范式构成了对现代金融学思维范式的挑战。该假说对金融市场整体控制也有重要的指导意义。     

关于有效市场假说的阐述

有效市场假说(Efficient Market Hypothesis,EMH)是一种建立在完全理性基础上的一种完全竞争市场模型,是传统主流金融学理论的奠基石。Fama(1970)对有效市场进行了全面阐述,并给出了一个研究EMH的完整理论框架,正式形成了有效市场理论。其核心是:有效市场中证券价格总是能够及时、准确、充分反映所有相关信息。Fama(1970)同时提出资本市场在不同信息环境下具有三种有效形式:弱式有效、半强式有效和强式有效。自此,以股票价格随机游走为理论精髓的有效市场假说达到了全盛时期。     

关于有效市场假说的阐述

有效市场假说(Efficient Market Hypothesis,EMH)是一种建立在完全理性基础上的一种完全竞争市场模型,是传统主流金融学理论的奠基石。Fama(1970)对有效市场进行了全面阐述,并给出了一个研究EMH的完整理论框架,正式形成了有效市场理论。其核心是:有效市场中证券价格总是能够及时、准确、充分反映所有相关信息。Fama(1970)同时提出资本市场在不同信息环境下具有三种有效形式:弱式有效、半强式有效和强式有效。自此,以股票价格随机游走为理论精髓的有效市场假说达到了全盛时期。     

有效市场假说在股市中的验证

本文先回顾了有效市场假说,重点分析了弱有效市场的理论与实证方法,用SAS软件对上证指数及其收益率的弱有效市场进行了验证,进而得出股市总体情况,还说明了有效市场假说的意义。     

有效市场假说的再思考

有效市场假说(Efficient Market Hypothesis,EMH)是一种建立在完全理性基础上的一种完全竞争市场模型,是传统主流金融学理论的奠基石。其核心是:有效市场中证券价格总是能够及时、准确、充分反映所有相关信息。Fama(1970)同时提出资本市场在不同信息环境下具有三种有效形式:弱式有效、半强式有效和强式有效。本文概述了有效市场假说的内容和面临的挑战,探讨了市场有效性对投资影响的两个重要方面:有限套利和噪声交易,得出了不同条件下相应的投资路径选择。     

不完全反映假说:有效市场假说的一种替代

按照有效市场假说(Efficient Market Hypothesis,EMH)最流行的解释,资产的市场价格充分反映了所有可以公开获得的信息(指弱势有效)。但是我们看到,投资者总是试图发现那些价格偏离其内在价值的股票,尽管EMH认为这是徒劳的;企业管理层总是试图将利空消息隐藏在脚注里,而监管当局则尽量消除这些做法,尽管EMH认为不管信息以何种方式呈报,都会反映在股票价格中。因此,实务界和监管当局似乎并不相信该假说。即使在学术界,EMH也受到了越来越多的实证证据的挑战。但因为没有人提出一种替代的假说来解释市场为何会失效以及如何失效,一些学者(…     

基于分形理论的资本市场非线性研究框架

基于资本市场的复杂性与非线性特征,提出了一个研究资本市场的非线性分析范式.该研究范式主要理论假说有:有限理性人、分形市场假说与分数布朗运动.它不同于基本有效市场假说的线性分析范式.资本市场的非线性分析框架为研究资本市场提供了一个新的视角.     

Samuelson Hypothesis & Indian Commodity Derivatives Market

Samuelson (1965) devised that futures price volatility increases as the futures contract approaches its expiration. The relation amid the volatility and time to maturity has significant inference for hedging strategies. Interestingly, so far the empirical evidence in favor of the Samuelson Hypothesis (maturity effect) is mixed in various markets. Considering no significant work to examine the relationship is so far carried out in commodity derivative markets of India, this paper ordeal the Samuelson Hypothesis on 8 commodities traded on Multi-Commodity Exchange (MCX), India. We have examined the issue by applying different regression techniques to test the hypothesis for 8 commodities (Aluminium, Nickel, Copper, Gold, Silver, Natural Gas, Crude Oil and Wheat) using inter-day data on MCX India. In order to test the Samuelson’s hypothesis, tests have been conducted using a series of GARCH, EGARCH and TGARCH models by including trading volume, open interest and time-to-maturity in the conditional variance equation. From our results, it is concluded that Samuelson’s hypothesis does not hold true for majority of commodity contracts considered. Our results also find that volatility series depend on the trading volume, compared to the time-to-maturity or open interest. As Samuelson hypothesis does not hold true for majority of commodity contracts, traders in Indian commodity derivative markets should not bias their decisions solely based on the time-to-maturity, but should also consider trading volume and open interest as they are an important determinant of price volatility. They should also consider the possibility of leverage effect while predicting future price volatilities, and the associated margin requirements.     

分形市场理论在大豆期货市场中的实证研究

本文以大连期货交易所大豆期货价格的日收盘价为样本,运用重标级差来研究期货市场价格的非线性特征.从统计结果来看,样本序列呈现出尖峰、胖尾等有偏特征,其H值大于0.5.这说明期货价格波动并不遵循有效市场理论,期货价格时间序列具有持久性趋势.同时发现,连豆期货存在着一个大约516天的非周期循环长度,这进一步证明期货市场价格波动的非随机性.     

The Random Walk Hypothesis in the Emerging Indian Stock Market

This paper examines the random walk hypothesis in the emerging Indian stock market using daily data on individual stocks. The statistical evidence in this paper rejects the random walk hypothesis. The results suggest that daily returns earned by individual stocks and by an equally weighted portfolio show significant non–linear dependence and persistent volatility effects. The non–linear dependence takes the form of ARCH–type conditional heteroskedasticity and does not appear to be caused by nonstationarity of underlying economic variables. Though conditional volatility is time varying, it does not explain expected returns.     

Reflections on the Efficient Market Hypothesis: 30 Years Later

In recent years financial economists have increasingly questioned the efficient market hypothesis. But surely if market prices were often irrational and if market returns were as predictable as some critics have claimed, then professionally managed investment funds should easily be able to outdistance a passive index fund. This paper shows that professional investment managers, both in The U.S. and abroad, do not outperform their index benchmarks and provides evidence that by and large market prices do seem to reflect all available information.     

有效市场检验、行为金融学与资本市场异象

有效市场假说理论及其检验同行为金融文献对有效市场这一命题给出了不同的答案,并提供了认知市场与股价行为不同的思维逻辑.面对两种理论(观点)由过去的分歧到当前的潜在融合,本文试图从历史的视角梳理传统金融难以解释的资本市场异常现象,审视人们对有效市场的证明和检验,并站在融合两者理论观点的基础上提出未来针对有效市场的研究方向.     

市场竞争的基金治理效应:理论假说与实证检验

论文首先提出了"市场竞争的基金治理效应假说",在此基础上论文以开放式基金为例对我国基金层面的市场竞争结构进行了考察,发现我国基金业存在大基金垄断和一定程度的过度竞争并存的问题;进一步,论文首次给出了衡量基金治理效率的指标体系,并通过实证检验证实了治理效应假说存在,即市场竞争结构对基金治理具有显著影响。     

The Unbiasedness Hypothesis in the Freight Forward Market: Evidence from Cointegration Tests

The current paper investigates the unbiasedness hypothesis of Forward Freight Agreement (FFA) prices in the freight over-the-counter (OTC) forward market trades. Cointegration techniques are employed to examine the hypothesis. The results indicate that: FFA prices one and two months before maturity are unbiased predictors of the realised spot freight rates for all investigated shipping routes; three months FFA prices for panamax Pacific routes are unbiased predictors of spot prices, while FFA prices for panamax Atlantic routes are found to be biased predictors of spot prices. This diverse evidence suggests that the validity of the unbiasedness hypothesis depends on the specific characteristics of the market under investigation, the selected trading route and the time to maturity of the contract. JEL classification G13, G14, C32