市场与行业因素对国际资产配置绩效的影响分析

本文采用基于“均值一方差”模型的“事后”检验和基于随机规划的动态资产配置模型的“事前”检验两种方法，比较了7种国际化投资组合的投资绩效，结果显示在投资组合中包含国际资产能够改善资产组合的整体风险收益特征，而随着国际上主要证券市场之间相关性的增加，采用“行业分散化原则”进行资产配置的效果相对更好；考虑到预测的不确定性、交易成本及无风险资产等因素，采用“中国市场指数＋全球行业指数”是相对较好的组合模式。     

基于均值——VAR的投资组合模型

本文对Markowitz投资组合模型的缺陷进行简要分析与概括,利用均值-VAR模型将VAR约束引入Markowitz投资组合理论中,使用VAR代替收益率方差来度量风险,建立基于VAR约束下的投资组合模型。     

基于均值——VAR的投资组台模型

本文对Markowitz投资组合模型的缺陷进行简要分析与概括,利用均值-VAR模型将VAR约束引入Markowitz投资组合理论中,使用VAR代替收益率方差来度量风险,建立基于VAR约束下的投资组合模型.     

存在无风险资产和投资比例限制的加权可能性模型及应用研究

本文以模糊变量的截集为切入点,给出随机变量取值为模糊数时加权可能性均值、方差和协方差的定义,将其分别作为证券投资收益为模糊数时未来收益、风险和不同证券收益之间相关程度的度量,构建了基于加权可能性均值-方差的组合投资决策模型;通过在加权可能性均值-方差模型中加入无风险资产和投资比例限制而使模型结构更加完整,应用过程中更加贴近实际情况,并结合中国证券市场的实际运行状况将三个模型的实证结果进行了对比分析。     

贝塔系数是风险的正确度量吗

在经典的投资组合理论中 ,假设所有资产的报酬率服从对数正态分布 ,因而只需要用收益的方差来度量风险就足够了 ,忽略了偏度的影响。资产收益的分布往往不是对称的 ,偏度是客观存在的 ,而且投资者具有正偏度的爱好。所以必须用方差和偏度来共同度量投资的风险 ,在这种情况下 ,贝塔系数不再是风险的正确度量 ,采用有效的修正方法 ,可以用来对资产进行正确的定价     

组合投资的系统风险与非系统风险——兼评王辉等人的《投资组合风险的分散化研究》

本文在指出王辉等人的《投资组合风险的分散化研究》一文中出现的错误的基础上,根据资本资产定价模型(CAPM)将组合投资的风险分离为系统风险与非系统风险,最后讨论了组合投资的均值-方差模型。     

Markowitz投资组合模型的优化研究

由于Markowitz投资组合模型过于严格的假设,它在中国证券市场的应用上存在一定的局限性。本文在Markowitz均值—方差模型的基础上,对模型中不符合中国证券市场的理想化假设进行修正,通过对预期收益率和风险进行优化度量,将交易费用、最小交易数量等限制条件引入模型,实现了对均值—方差模型的优化,得到了在不同优化背景下的新的数学模型。     

基于VaR的证券组合优化方法

基于VaR的最优投资决策问题,给出了在VaR约束下的投资组合优化模型。该模型在马柯维茨均值-方差模型的基础上,加入了VaR约束,保证了其风险度量手段与我国金融机构现有投资选择方法在技术上的一致性。     

证券投资组合优化问题研究——基于资产定价理论

资产定价理论的核心问题是如何确定资产的期望收益和风险。其中,资本资产定价模型和套利定价理论是常见的模型和方法。在基于资产定价理论的证券投资组合中,需要考虑资产类别选择和投资比例限制,并定义目标函数。优化算法包括均值—方差模型和更高级的算法,如进化算法和粒子群优化算法。改进方向包括考虑非理性行为因素、市场微结构因素和动态调整的优化模型。     

利用期货投资基金规避证券组合风险的实证研究

本文对股票、债券、股指期货、商品期货四类资产,采用华夏大盘精选、南方50、沪深300股指期货、和CRB商品期货指数,逐步构建投资组合来研究期货投资基金对证券组合风险的影响。期货投资基金同股票及债券投资的弱相关性,使之成为大资金规避投资风险的良好投资工具,我们通过均值-方差边界、最大Sharpe比率、以及Ω比率确定了适合我国特点的投资组合(股票、债券、股指期货、商品期货),权重分别为(0.36,0.24,0.38,0.02),该组合规避了传统证券投资组合89.81%方差风险,并在采用Ω比率指标验证该组合具有最优的预期收益比。     

基于风险预算的新疆居民家庭金融资产的风险资产配置

通过对新疆2013-2017年的居民家庭金融总资产以及投资和储蓄的分析,从宏观的家庭金融资产视角使用Markowitz的投资组合的均值-方差模型在风算预算的基础上,进一步计算出实际新疆居民每年应当用于储蓄或者用于投资与固定风险和较大风险的比例,即得出风险资产的配置,从而提高新疆居民的储蓄向投资的转化,加强居民金融资产的管理和风险资产的分配,提高居民的风险收益,为新疆居民家庭获取更多金融资产投资于风险性收入提供更好的政策建议。     

INVESTING WITH LIQUID AND ILLIQUID ASSETS

We find optimal trading policies for long‐term investors with constant relative risk aversion and constant investment opportunities, which include one safe asset, liquid risky assets, and an illiquid risky asset trading with proportional costs. Access to liquid assets creates a diversification motive, which reduces illiquid trading, and a hedging motive, which both reduces illiquid trading and increases liquid trading. A further tempering effect depresses the liquid asset's weight when the illiquid asset's weight is close to ideal, to keep it near that level by reducing its volatility. Multiple liquid assets lead to portfolio separation in four funds: the safe asset, the myopic portfolio, the illiquid asset, and its hedging portfolio.     

风险态度、金融教育与家庭金融资产选择

文章基于中国城市居民消费金融调查数据,研究了风险态度、金融教育对家庭金融资产选择和家庭金融市场参与的影响。结果发现,风险态度显著影响家庭金融资产组合分散化程度,风险厌恶程度越高,金融资产组合分散化程度越低。风险态度对家庭正规金融市场参与有显著影响,风险厌恶程度的提高会显著降低家庭在股票、基金、债券、储蓄性保险市场的参与概率,风险厌恶程度增加一单位,家庭参与股票市场的可能性会降低10.5%。风险厌恶程度对股票、基金、债券、储蓄性保险资产在家庭金融资产中的比例具有显著的负向影响。家庭的金融教育投入对风险资产持有比重条件分布的影响上,呈先上升后下降趋势,中间分位的要大于两端。文章相应的政策含义是,政府及金融管理部门需要普及金融教育知识,提高居民的金融风险认知水平,从而优化家庭金融资产选择,改善居民金融福利。     

新型监管政策下我国保险资金的资产配置研究——基于大类资产监管和“偿二代”的政策背景

近年来我国保险资金运用监管开始实行“放开前端、管住后端”的政策理念,在前端实行的是资产大类监管政策,在后端实行的是“偿二代”政策。在此新的政策背景下,保险公司如何优化投资结构是一项非常重要的问题。考虑到我国保险业实际监管政策内容,以投资组合的风险最低资本的最小化为优化目标,以大类监管政策中的投资比例限制为约束条件,建立了一个新的投资组合模型,用来计算出各种最优投资组合比例。研究结果表明：在新监管政策下,协议存款、基础设施和不动产的理论配置比例较高, 债券类投资和权益类投资的理论配置比例较低。与理论投资比例相,债券类产品的实际投资比例偏高,而不动产类投资品的实际投资比例偏低,所以我国保险资金在今后的大类资产配置中,应当降低债券的投资比例,适当提高不动产的投资比例。     

Choosing an optimal investment strategy: The role of robust pair-copulas based portfolios

This paper is concerned with the efficient allocation of a set of financial assets and its successful management. Efficient diversification of investments is achieved by inputing robust pair-copulas based estimates of the expected return and covariances in the mean-variance analysis of Markowitz. Although the whole point of diversifying a portfolio is to avoid rebalancing, very often one needs to rebalance to restore the portfolio to its original balance or target. But when and why to rebalance is a critical issue, and this paper investigates several managers' strategies to keep the allocations optimal. Findings for an emerging market target return and minimum risk investments are highly significant and convincing. Although the best strategy depends on the investor risk profile, it is empirically shown that the proposed robust portfolios always outperform the classical versions based on the sample estimates, yielding higher gains in the long run and requiring a smaller number of updates. We found that the pair-copulas based robust minimum risk portfolio monitored by a manager which checks its composition twice a year provides the best long run investment.     

基于VaR和两基金分离的投资组合模型

本文使用VaR来度量投资组合的市场风险,构造了一个在可接受期末财富约束条件下,使VaR达到最小的投资组合模型,同时,发现该模型发生了两基金分离现象,因此存在多风险资产情形下的投资组合模型可以退化成为单风险资产情形下的投资组合模型。最后,本文使用简化的单风险模型对我国上海股票市场进行了实证分析,探讨投资者如何在股票和银行借贷中进行最优资产分配。     

RISK‐MINIMIZATION FOR LIFE INSURANCE LIABILITIES WITH DEPENDENT MORTALITY RISK

In this paper, we study the pricing and hedging of typical life insurance liabilities for an insurance portfolio with dependent mortality risk by means of the well‐known risk‐minimization approach. As the insurance portfolio consists of individuals of different age cohorts in order to capture the cross‐generational dependency structure of the portfolio, we introduce affine models for the mortality intensities based on Gaussian random fields that deliver analytically tractable results. We also provide specific examples consistent with historical mortality data and correlation structures. Main novelties of this work are the explicit computations of risk‐minimizing strategies for life insurance liabilities written on an insurance portfolio composed of primary financial assets (a risky asset and a money market account) and a family of longevity bonds, and the simultaneous consideration of different age cohorts.     

CONSTANT PROPORTION PORTFOLIO INSURANCE IN THE PRESENCE OF JUMPS IN ASSET PRICES

Constant proportion portfolio insurance (CPPI) allows an investor to limit downside risk while retaining some upside potential by maintaining an exposure to risky assets equal to a constant multiple of the cushion , the difference between the current portfolio value and the guaranteed amount. Whereas in diffusion models with continuous trading, this strategy has no downside risk, in real markets this risk is nonnegligible and grows with the multiplier value. We study the behavior of CPPI strategies in models where the price of the underlying portfolio may experience downward jumps. Our framework leads to analytically tractable expressions for the probability of hitting the floor, the expected loss, and the distribution of losses. This allows to measure the gap risk but also leads to a criterion for adjusting the multiplier based on the investor's risk aversion. Finally, we study the problem of hedging the downside risk of a CPPI strategy using options. The results are applied to a jump-diffusion model with parameters estimated from returns series of various assets and indices.     

Volatility and shock interactions and risk management implications: Evidence from the U.S. and frontier markets

The study affords comprehensive evidence of shock and volatility interactions between stock markets of each of the twenty four frontier markets and the U.S. for the period 2006:01 to 2015:07. The results from the recent EDCC-GARCH model of Nakatani and Teräsvirta (2009), which permits for concurrent estimation of shock and volatility interactions as well as dynamic conditional correlations (DCC) across assets, shows unidirectional shock and volatility transmissions from the U.S. to the frontier markets. The conditional correlation between the U.S. and each frontier market is very low or negative, offering diversification benefits to U.S. investors. The DCC exhibits slow decay and is insignificantly impacted by previous period's shocks. The results are very intuitive for optimal portfolio allocations using the traditional capital-based as well as the risk-based allocations. The risk parity approach to portfolio management increases (reduces) allocations to lower (higher) risk assets to improve portfolio diversification while increasing the risk-adjusted returns.     

Asymmetric Correlations in Predicting Portfolio Returns*

Rigorous statistical tests have been designed to detect the existence of asymmetric correlations. However, these tests can hardly further facilitate future investment or risk management because asymmetric correlations are time‐varying and difficult to predict. In this paper, we construct a unified state‐space model, which not only measures in‐sample asymmetric correlations, but also exploit out‐of‐sample asymmetric correlations in the context of predicting portfolio returns. First, we regard time‐varying correlation between market returns and portfolio returns as a state variable and model it as an AR(1) process. Then, we measure future asymmetric correlations based on correlation coefficients between two unpredictable components in market returns and correlation, respectively. Third, we clarify the intuition, calculate asymmetric correlations for two portfolio sets and estimate the economic value of applying our model in asset allocation. Finally, we try to search for potential variables that can explain future asymmetric correlations. The results show that market‐wide liquidity, variance, earning price ratio, and investor sentiment can partially explain the asymmetry correlation phenomenon.