含资本结构因子和交易费用的CVaR投资组合模型分析

在资本市场上,资本结构因子和交易费用对投资组合决策的影响是现实存在的,而完全竞争市场假设的投资组合模型缺乏实用的指导意义.基于改进的、含有资本结构因子和交易费用的CVaR投资组合模型的分析表明,资本结构因子和交易费用的变动会引起CVaR投资组合有效前沿的移动和上下限的变动.     

Continuous-time mean–variance portfolio selection with only risky assets

We investigate in this paper a continuous-time mean–variance portfolio selection problem in a general market setting with multiple assets that all can be risky. Using the Lagrange duality method and the dynamic programming approach, we derive explicit closed-form expressions for the efficient investment strategy and the mean–variance efficient frontier. We provided a necessary and sufficient condition under which the global minimum variance is zero and there exists a risk-free wealth process. Our results reveal that, even if there is no risk-free asset in the market, there can still exist a risk-free wealth process, the global minimum variance can be zero, and the efficient frontier can be a straight line in the mean–standard derivation plane. In addition, we further prove the validity of the two-fund separation theorem.     

Leverage versus volatility: Evidence from the capital structure of European firms

The impact of leverage on financial market stability and the relationship with the real economy is a key concern among researchers. This paper makes an initial attempt to investigate the relationship between a firm’s leverage, return and share price volatility from an Islamic finance perspective and capital structure theory. A multi-country dynamic panel framework and the mean-variance efficient frontier are applied to 320 sample firms from eight European countries, divided into portfolios of low and high debt using the shari’ah screening threshold of 33%. We find that the firm’s return and volatility change with changes in the capital structure. Islamic-compliant stocks show, in most cases, less volatility than non-compliant stocks but are no different in terms of return. Finally, our results tend to imply a case for limiting debt beyond certain levels.     

完善公司治理有赖于有效的资本市场

现代市场经济中，有效的资本市场成为委托人监督代理人的主要路径依赖，成为完善公司治理的一个重要环节。我国资本市场由于制度设计上的缺陷，不能对上市公司的规范经营形成有效的约束，不利于上市公司治理的改进和完善；我国上市公司治理的不建全，除与公司内部治理结构的不合理有关外，还与公司运营的资本环境的不完善有关。完善我国上市公司的治理有赖于有效的资本市场。     

Multi-period Markowitz's mean–variance portfolio selection with state-dependent exit probability

This paper considers a multi-period mean–variance portfolio selection problem with uncertain time-horizon in a regime-switching market, where the conditional distribution of the time-horizon is assumed to be stochastic and depends on the market states as the returns of risky assets do. Existence of the optimal investment strategy is analyzed, and the closed-form expressions for the optimal investment strategy and the efficient frontier are derived. In addition, some interesting properties of the efficient frontier are illustrated by numerical analysis and by comparing with the efficient frontier of the case where the distribution of the uncertain time-horizon does not depend on market states.     

保险公司不动产最优投资策略研究

本文研究了保险公司投资不动产时的最优投资策略问题。本文假设保险公司的风险过程为经典Cramer-Lundeberg模型。保险公司可把资金投资于现金市场和两个风险市场,分别为债券、股票和不动产。在卖空、借贷限制下,基于均值—方差模型,应用辅助随机二次线性问题求解方法,得到最优投资策略和有效边界。研究结果显示,不动产最优投资量不仅与初始资本金存在非简单线性关系,还与不动产的市场溢价水平、未预期冲击存在一系列复杂关系。     

Information Technology and Productivity Changes in the Banking Industry

This paper analyses the effects of investment in information technologies (IT) in the financial sector using micro-data from a panel of 600 Italian banks over the period 1989–2000. Stochastic cost and profit functions are estimated allowing for individual banks' displacements from the best practice frontier and for non-neutral technological change. The results show that both cost and profit frontier shifts are strongly correlated with IT capital accumulation. Banks adopting IT capital-intensive techniques are also more efficient. On the whole, over the past decade IT capital-deepening contribution to total factor productivity growth of the Italian banking industry can be estimated in a range between 1.3 and 1.8 per cent per year.     

董事会激励对公司效率影响的随机前沿分析

本文将激励形式分为两种内部激励——显性激励、隐性激励和两种外部激励——产品市场压力、资本市场压力,并以2005—2008年度中国纺织服装行业上市公司为样本,利用随机前沿模型实证分析了董事会激励对公司效率的影响。结果表明:显性激励方面,董事会薪酬激励优于权益激励;隐性激励方面,董事长更替对公司效率有积极显著的影响,而董事长和总经理的两职合一对公司效率有负面的影响。外部激励方面,产品市场的竞争压力比资本市场的收购风险对公司董事会更有约束力。     

Creative destruction on the Chechen frontier?

The economic performance of Chechnya is examined for the first time using an aggregate stochastic frontier production function method. The 15 sectors of the economy are found to be quite inefficient in the use of capital and labour to produce aggregate output. Extensive growth is likely to continue though at a lower rate as federal subsidies from Moscow end. Intensive growth is unlikely given the lack of foreign investment and the authoritarian political system. Some evidence for the emergence of a market economy is found, suggesting that Kadyrov has overseen an economic transition.     

ANALYSIS OF POVERTY AND EFFICIENCY: AN EARNINGS FRONTIER APPROACH

The paper introduces the concept of an earnings frontier in explaining monthly consumption expenditure (a proxy for income) in terms of human capital and endowments of a household. Individuals who translate their potential earning into actual earnings enjoy a fully efficient position. In contrast, individuals who earn less than their potential earnings suffer from some kind of earnings inefficiency. The paper estimates an earnings frontier using the Corrected Ordinary Least Square (COLS) method and classifies households in terms of efficiency scores. Splitting the sample into an efficient and an inefficient part based on the estimated frontier and a bench mark efficiency score, the status of poverty in the two parts (groups) is studied. The poverty gap between the groups is then decomposed into a characteristics effect and a coefficients effect using the familiar Oaxaca decomposition methodology. The paper also tries to establish a link between the notion of efficiency and the coefficients effect in the Oaxaca decomposition methodology. The results obtained are interpreted in light of the poor but efficient hypothesis.     

Human capital effects on technical inefficiency: a stochastic frontier analysis across industries of the Greek economy

In this paper we examine the impact of human capital on technical inefficiency. A stochastic production frontier is simultaneously estimated with a technical inefficiency model using data from one-digit industries of the Greek economy, for the period 2000–2005. The results indicate a significantly negative impact of human capital on technical inefficiency, which is comparatively lower in magnitude for the sector of public services. The most efficient industries of the Greek economy are those of Education, Financial intermediation and Real estate, renting & business activities. The highest contribution of human capital on technical efficiency is observed in the industries of Health, Education and Real estate, renting & business activities.     

货币传导效率对货币当局的认知冲击

如果货币政策通过资本渠道传导不畅,现金资产大量滞留在资本市场中,当货币扩张(紧缩)时,实体部门可能并不发生相应的资本流入(流出),则货币当局可能产生"上次货币调整的效果不显著"的错觉,促使其发动新一轮更大强度的同向货币政策调整,这将加重国内整体经济和资本市场的动荡。通过对近十余年来货币供给量、资本市场规模和资产价格的实证分析,发现我国资本市场中的政策信息阻塞现象的确会引起货币当局的错觉,而导致国内经济更加不稳定。     

货币调整中我国资本市场信息传递效果研究

根据对1998~2009年间我国货币供应量、利率、股票市场规模、实体经济的四变量VAR模型分析判断,我国资本市场并不能对以经济增长为目标的货币政策调整信息进行及时有效的传导;且引起了货币当局产生上期货币政策调整不够的认识误差。这些情况实际反映出货币调整不足以使公众对未来经济,尤其是实体经济保持乐观预期。我国应努力不断改进实体经济的健康运行机制,以使公众对未来经济保持稳定和较高的收益预期。     

Public and private inputs in aggregate production and growth: a cross-country efficiency approach

In a cross section of OECD countries, we replace the macroeconomic production function by a production possibility frontier, total factor productivity being the composite effect of efficiency scores and possibility frontier changes. We consider, for the periods 1970, 1980, 1990 and 2000 one output – GDP per worker – and three inputs – human capital, public physical capital per worker and private physical capital per worker. We use a semi-parametric analysis, computing Malmquist productivity indexes, and we also resort to stochastic frontier analysis. Results show that private capital is important for growth, although public and human capital also contribute positively. A governance indicator, a nondiscretionary input, explains inefficiency. Better governance helps countries to achieve a better performance. Nonparametric and parametric results coincide rather closely on the movements of the countries vis-à-vis the possibility frontier and on their relative distances to the frontier.     

中国权证市场有效性的方差比检验

中国资本市场是否弱式有效一直是争论的热门话题,它具有很重要的理论价值和实践意义.本文利用方差比检验方法来对中国权证市场的弱式有效进行实证研究.结果显示:中国权证市场不符合随机游走假设,即权证市场未达到弱式有效.     

有效市场假说对会计的影响

在有效市场假说下,股票价格总能及时、准确、充分地反映所有相关信息。也就说,股票价格是绝大多数投资者对各种信息进行综合分析判断的均衡值,反映了资本市场上绝大多数投资者根据已有信息对公司价值的总体预期。有效市场假说对信息与价格的关系认知,推动了对会计信息作用的再认识,促进了决策有用性目标的确立,促使会计研究由规范研究转向实证研究,实证检验会计信息的有用性。     

HUMAN CAPITAL AND CONVERGENCE: A PRODUCTION‐FRONTIER APPROACH*

Using nonparametric, production‐frontier methods, we decompose labor productivity growth into components attributable to technological change (shifts in the world production frontier), technological catch‐up (movements toward or away from the frontier), and physical and human capital accumulation (movements along the frontier). We find that (1) technological change is decidedly nonneutral, (2) productivity growth is driven primarily by physical and human capital accumulation, (3) the increased international dispersion of productivity is explained primarily by physical capital accumulation, and (4) international polarization (the shift from a unimodal to a bimodal distribution) is brought about primarily by efficiency changes (technological catch‐up).     

从要素市场化看供给侧改革的中长期实践路径*——基于随机前沿模型增长核算的分析

本文从要素市场化角度分析中国供给侧改革的中长期实践路径。从经济增长核算的角度出发,本文基于2005—2013年全国分省面板数据,通过超越对数生产函数形式的随机前沿模型测算经济增长来源并分解全要素生产率,发现TFP是非农经济增长的主要来源。然而TFP分解中技术效率偏低,且逐年下降,成为阻碍TFP增长以及经济增长的一大桎梏,而要素市场扭曲是技术效率项偏低的重要原因。促进要素市场化能够推进要素向高效企业流动,进而提高社会整体生产效率水平,本文认为,这是中国供给侧结构性改革的中长期实践路径。     

The instantaneous capital market line

Summary. We show that if the intercept and slope of the instantaneous capital market line are deterministic, then investors will not hold any hedge portfolios in the sense of Merton [9, 11]. They will choose portfolios that plot on the capital market line, and they will slide up and down the capital market line over time as their wealth and risk tolerance change. This result allows us to aggregate over investors and derive a single factor CAPM where the first and second moments of security returns may change stochastically over time and markets are potentially incomplete.Received: 21 June 2004, Revised: 10 December 2004, JEL Classification Numbers: G11, G12.An earlier version of this paper was presented at the Econometric Society Meeting in Pasadena (1997) under the title “Portfolio selection and asset pricing with dynamically incomplete markets and time-varying first and second moments”.     

FOREIGN CAPITAL AND EFFICIENCY IN DEVELOPING COUNTRIES

This paper uses stochastic frontier methodology to analyse foreign direct investment, imported capital goods and human capital as channels for increased efficiency in less‐developed countries. Empirical investigation reveals that developing countries differ with respect to the efficiency with which they use frontier technology. Foreign direct investment and human capital play a significant and quantitatively important role in explaining these differences.