代理证券相对有效性

分析了具有特定的期望收益率向量R与风险因子向量β截面关系的代理证券组合边界,进而研究了代理证券组合边界与有效证券组合边界的差异以及代理证券相对有效度。     

资本结构变化对组合投资有效边界的影响

在经典的组合投资均值-方差模型基础上,本文考虑融资因素对组合投资优化的影响,引入资本结构摩擦因子,研究其对组合投资有效边界的影响;给出了含资本结构摩擦因子作用的组合投资有效边界解析式,以及该有效边界根据资本结构因子取值而移动、变化的性质。     

具有资本结构因子和交易成本的证券组合投资模型

在介绍经典的Harry Markowitz均值-方差投资组合模型的基础上,建立了含有资本结构因子和交易成本的证券组合最优化模型,在组合中不含有无风险证券和含有无风险证券的条件下,分别给出最优投资比例及有效边界,并讨论了资本结构因子与交易成本对有效边界的影响.     

证券组合投资有效集及有效边界的确定的方法研究

证券组合投资有效集及有效边界是确定合理投资结构的关键。本文研究了证券组合投资风险函数及有效边界的凹性，提出了将求最小风险的干净人规划问题转化为线性规划问题，并根据其最优基及其灵敏度分析，分段确定有效边界的方法。这种方法使各段有效边界可直接由相应的数学表达式求得，计算量大大减少。     

证券市场中股票成交量对投资组合优化的影响

将证券市场中股票成交量引入组合投资模型, 得出新的有效边界解析式, 并探讨了新有 效边界与未考虑成交量有效边界之间的关系; 利用深圳股票交易市场的数据进行了实证分 析, 初步验证了这种关系.     

组合证券资产选择的模糊最优化模型和有效边界的研究

本文针对组合让券资产选择问题,提出了兼顾收佃与风险的模糊最优化模型,给出了最优证券组合的计算方法,并对允许卖空与允许地空情况下的有效边界进行了研究。     

限制性卖空情况下组合证券有效边界的特征和确定方法

限制性卖空的引入有助于扩展投资机会空间，增强市场效率，本文在以往研究基础上，进一步讨论了允许限制性卖空情况下组合证券投资有效边界的特征，得出了有意义的结论。文中还针对收益率协方差矩阵的结构特征，提出了一种相对于文献的方法计算效率更高、可连续确定有效组合构成和有效边界的参数单纯形方法。     

风险资产组合的均值一CVaR有效前沿（1）

本文基于CVaR风险计量技术,讨论了正态情形下风险资产组合的均值-CVaR边界,探究了其经济含义,并与经典的方差风险下的均值-方差边界进行了对比研究,为彻底解决均值-CVaR的有效前沿问题提供了基础.     

确定组合证券投资有效边界的参数线性规划方法

本文从预期收益率与风险权衡的分析，导出了连续确定组合证券投资有效边界的一种简化参数线性规划方法，研究了不允许卖空情况下有效边界的一般形状，并将有关方法和结论推广到包含一般线性的约束和无风险证券的情况，指出了有效边界出现不可导点的可能性。     

基于均值-AS模型的资产配置

AS指标是诺贝尔经济学奖得主Aumann与其合作者Serrano近期基于不确定条件下的选择理论提出的新的风险度量指标,具有诸多优点,被学者们广泛关注.本文基于均值-AS模型研究了正态分布和一般分布下的资产配置问题.在正态分布下,得到了组合边界的解析式,深入探讨了组合边界的特征.在一般分布下,将AS指标的矩估计式嵌入均值-AS模型,实现了风险估计与投资组合优化同步进行.在较弱的条件下,证明了均值-AS模型是凸优化问题,可基于迭代思想设计算法得到模型的数值解.蒙特卡洛模拟结果表明该模型和算法准确有效.最后,基于中国A股市场数据给出了实例分析.     

Evaluating the quality of solutions in project portfolio selection

Assessing the quality of decisions while selecting project portfolios becomes an inherent part of the decision-making process when the project parameters are inaccurate or uncertain. Small adjustments to the initial parameters can lead to situations where the preferred portfolio no longer reflects the investor’s requirements. The paper studies the post-optimal analysis of the Pareto optimal portfolios chosen by Savage’s risk criteria. Stability characteristic, such as the stability function, is considered. Using the stability function, we evaluate the quality of feasible portfolios. This function indicates the robustness of portfolios to any changes in the initial data. Using the stability function the formula for calculating the optimality threshold is obtained, which determines the level of risk reduction when the selected Pareto optimal portfolio can obtain optimal properties. The performances of the stability function and the optimality threshold are shown in the case study using global risk assessments for projects participating in the Belt and Road Initiative. The computation results demonstrate the ability through the stability function to evaluate the quality and optimal properties of feasible project portfolios.     

Beyond Markowitz with multiple criteria decision aiding

The paper is about portfolio selection in a non-Markowitz way, involving uncertainty modeling in terms of a series of meaningful quantiles of probabilistic distributions. Considering the quantiles as evaluation criteria of the portfolios leads to a multiobjective optimization problem which needs to be solved using a Multiple Criteria Decision Aiding (MCDA) method. The primary method we propose for solving this problem is an Interactive Multiobjective Optimization (IMO) method based on so-called Dominance-based Rough Set Approach (DRSA). IMO-DRSA is composed of two phases: computation phase, and dialogue phase. In the computation phase, a sample of feasible portfolio solutions is calculated and presented to the Decision Maker (DM). In the dialogue phase, the DM indicates portfolio solutions which are relatively attractive in a given sample; this binary classification of sample portfolios into ‘good’ and ‘others’ is an input preference information to be analyzed using DRSA; DRSA is producing decision rules relating conditions on particular quantiles with the qualification of supporting portfolios as ‘good’; a rule that best fits the current DM’s preferences is chosen to constrain the previous multiobjective optimization in order to compute a new sample in the next computation phase; in this way, the computation phase yields a new sample including better portfolios, and the procedure loops a necessary number of times to end with the most preferred portfolio. We compare IMO-DRSA with two representative MCDA methods based on traditional preference models: value function (UTA method) and outranking relation (ELECTRE IS method). The comparison, which is of methodological nature, is illustrated by a didactic example.     

价值与动量混合策略DEA多期限资产组合选择及效率评价

运用DEA融合有效价值与有效动量指标,构造多期限价值与动量混合策略资产组合,在期望收益率与风险调整收益率条件下评价其相对有效性。基于沪深300成分股的实证发现,DEA高效率值股票组合持有期期望收益率显著高于沪深300组合,且期望收益率与风险调整收益率均高于单一价值股票组合和赢者股票组合;在此基础上,构造同时持有DEA高效率值股票组合多头与DEA低效率值股票组合空头的套利交易策略,在相对较长的持有期上能给投资者带来显著的超额收益率。     

STOCHASTIC DOMINANCE AS A RISK ANALYSIS CRITERION*

This paper discusses the Stochastic Dominance (SD) approach to the evaluation of risky assets. Given a set of portfolios, the familiar EV procedure chooses a set of EV-efficient portfolios while the SD procedures choose SD-efficient sets that usually are quite similar to (but not identical with) the EV-efficient set. The SD approach can be employed as a refinement of the EV model or as an alternative method of evaluating portfolios. The SD view has certain conceptual advantages in the screening of a set of portfolios, but the EV model has the important advantage of an optimizing algorithm that builds efficient portfolios. Also, the SD approach requires more data than the EV approach.     

DIVERSIFICATION GAINS FROM INCLUDING REAL ESTATE IN MIXED-ASSET PORTFOLIOS*

Diversification gains in mean-variance efficiency derived from including real estate in financial asset portfolios are examined. Optimal financial and mixed-asset portfolios were generated by selecting from an investment universe including several distinct financial and real estate media. Deficiencies of previous studies were overcome by employing data with improved representativeness and comparability. The efficient mixed-asset portfolios dominated the efficient financial asset portfolios implying that purely financial asset diversification is inefficient. The optimal mixed-asset portfolio prescribed that approximately two-thirds of the investment wealth be allocated to real estate and one-third to the financial media.     

受限制投资组合机会成本的实证研究

通过对只能投资于股票和只能投资于债券2种情况下的投资组合的机会成本的计算,研究了受限制情况下所产生效用损失和风险厌恶程度对机会成本的影响。计算中选用上证综合指数、深圳成分指数、中信国债指数、中信企债指数和银行间7日债券回购利率的5年期月度数据,运用向量自回归的方法估计下期组合的期望收益和收益的联合概率分布,并运用Quasi-Newton最优化方法来求得最优投资组合,从而求出机会成本。     

Absolute return portfolios

In this paper we consider the problem of selecting an absolute return portfolio. This is a portfolio of assets that is designed to deliver a good return irrespective of how the underlying market (typically as represented by a market index) performs. We present a three-stage mixed-integer zero-one program for the problem that explicitly considers transaction costs associated with trading. The first two stages relate to a regression of portfolio return against time, whilst the third stage relates to minimising transaction cost.We extend our approach to the problem of designing portfolios with differing characteristics. In particular we present models for enhanced indexation (relative return) portfolios and for portfolios that are a mix of absolute and relative return. Computational results are given for portfolios derived from universes defined by S&P international equity indices.     

OBTAINING AND PARAMETERIZING MULTIPERIOD PORTFOLIOS WITH DESIRABLE CHARACTERISTICS UNDER LOGNORMAL RETURNS

The expected geometric mean has been shown to be a valuable criterion in ranking portfolios of assets. For example, under certain conditions the maximum expected geometric-mean portfolio minimizes the expected time to amass a fixed level of wealth as wealth becomes “large.” This paper develops a simple algorithm for obtaining such portfolios when portfolio returns are assumed to be lognormally distributed. The risk-return characteristics of portfolios are derived and illustrated using data from a subset of stocks found on the New York Stock Exchange.     

Patent portfolios for strategic R&D planning

Empirical research has found a discrepancy between the perceived importance and the actual level of information on competitor's R&D strategies. It has been argued in the literature that patent information might be used to overcome this information deficit. However, empirical research further reveals that patent information is rarely used in strategic R&D planning. The present paper explores this issue and introduces two types of patent portfolios for strategic R&D planning. In patent portfolios on the company level, patenting strategies are identified and the quality of overall technological positions is benchmarked against relevant competitors. In addition, we present a patent portfolio on the technological level, which, as it is known from various technology portfolios, helps companies to manage the allocation of R&D resources effectively. Based on patent data from 21 German, European and Japanese mechanical engineering companies we show the application of both patent portfolios for strategic R&D planning purposes. The patent portfolios prove to be a very valuable tool for R&D decision makers in companies. Based on the experiences made in the case study, recommendation for the effective use of patent portfolios are formulated.     

全链接分散化多阶段投资组合评价研究

现有多阶段分散化投资组合评价模型都是基于各阶段实际收益率来构建的,然而由于投资组合在各阶段的联系主要体现在财富的动态变化过程中,因此基于财富动态方程来构建多阶段投资组合评价模型更加符合实际.本文基于投资组合与前沿面的距离,给出多阶段投资组合效率的定义.在均值-方差框架下,基于财富过程构建不同导向下的全链接分散化多阶段投资组合评价模型,利用动态规划方法得到投资组合效率的解析式.最后,通过数值仿真检验了传统多阶段分散化模型与本文所提出模型之间是存在显著差异的.