股权分置与中国上市公司多元化经营

本文剔除了上市公司中的相关多元化企业，以非多元化企业和不相关多元化企业为样本，区分了上市公司是否选择多元化经营战略和多元化上市公司具体选择多高的多元化程度两种情况．分别运用Logit模型和多元线性回归模型考察了股权分置对中国上市公司多元化经营的影响。实证分析结果表明，在控制了企业所处的行业、企业规模、技术水平和负债水平等因素后．股权分置对上市公司是否选择多元化经营以及对多元化上市公司多元化程度的选择均有显著影响。     

Open economy and financial burden of corruption: theory and application to Asia

We discuss why corruption remains high and show that corruption contributes to the Banking distress and to the rapid transmission across international stock and currency markets. Undeveloped ‘derivative securities’ markets make the risk from stress-induced volatility difficult to manage. Vinod’s (1999) closed economy model is extended to indicate the asymmetry of ‘home bias’ and the effect of corruption on the value at risk (VaR). Our theory predicts that capital flight controls will be many, foreign direct investment (FDI) will be low and cost of capital will be high in corrupt developing countries, which is supported by Asian data. We include some policy recommendations regarding financial institutions and markets.     

我国上市公司的多元化战略与公司绩效

本文以2004年深沪两市的696家非金融公司作为样本,通过建立有效的多元化经营指标,考察了中国上市公司多元化战略与其绩效(CROA)的关系。实证研究表明,多元化有一定的正面效应,即能够降低公司经营风险,但是从整体上来看,多元化的成本仍然大于收益,导致多元化程度与公司绩效负相关。这一实证结果与多元化给企业带来巨大成本的理论一致。     

Diversification, convex preferences and non-empty core in the Choquet expected utility model

Summary. We show, in the Choquet expected utility model, that preference for diversification, that is, convex preferences, is equivalent to a concave utility index and a convex capacity. We then introduce a weaker notion of diversification, namely “sure diversification.” We show that this implies that the core of the capacity is non-empty. The converse holds under concavity of the utility index, which is itself equivalent to the notion of comonotone diversification, that we introduce. In an Anscombe-Aumann setting, preference for diversification is equivalent to convexity of the capacity and preference for sure diversification is equivalent to non-empty core. In the expected utility model, all these notions of diversification are equivalent and are represented by the concavity of the utility index. Received: July 27, 1999; revised version: November 7, 2000     

多元化战略、经济绩效与资本结构——关于上市公司股权融资偏好解释

我国上市公司存在十分强烈的股权融资偏好,学术界一般将其原因归结为股权融资成本偏低。笔者研究则表明,融资成本因素并不能全部解释上市公司股权融资偏好。本文从企业多元化经营战略角度来剖析股权融资偏好。研究发现:企业多元化程度越低负债率越低,企业经济绩效越好;企业有动力降低负债率,采用股权融资。研究还发现,企业多元化战略已经构成融资决策的有效约束,股权融资偏好是上市公司的理性选择。     

企业多元化:理论与实践的反思

多元化是目前许多企业热衷的战略选择 ,成为企业心目中的“伊甸园”。本文作者从多元化发展的理论与实践及其历程入手进行分析 ,认为不论从多元化与企业分散风险、扩张规模、增加绩效之间的联系 ,还是从发达国家多元化的实践来看 ,多元化并没有达到人们预想的效果 ,而正确的选择是坚持走专业化的道路。     

Diversification Benefits of Japanese Real Estate Over the Last Four Decades

This paper studies the benefits of diversifying into real estate and other assets that typify the wealth held by Japanese investors. We examine movements in mean variance frontiers by employing spanning tests to assess the statistical significance of frontier shifts. We also investigate the impact of shifts in mean variance frontiers before and after the precipitous decline in Japanese real estate and stock market values that began in 1990. Spanning tests show that real estate, short and long-term bonds, and Japanese equity provide significant diversification benefits. We find that mean variance frontiers shift after 1990. Statistically significant shifts are also economically important as measured by Sharpe ratio changes. Although significant, the portfolio weights on Japanese real estate are relatively small compared to their composition found in surveys of Japanese household wealth.     

Diversified behavioral portfolio as an alternative to Modern Portfolio Theory

The traditional mean–variance approach has been complemented by alternative theories that use risk measures different from standard deviation of returns or involve additional distributional features of returns like skewness and kurtosis. We propose a portfolio choice model that combines different distributional characteristics of the returns in the decision-making making process, considering preferences of investors which are modeled as non-statistical uncertainties of investors using fuzzy theory. We use 20 stocks of the S&P500 from January 2013 to December 2017. We assess the obtained portfolios’ performance, and the diversified behavioral portfolios outperform than the mean–variance portfolio. This methodological proposal can be seen as a strong managerial tool to make investment portfolio decisions.     

Bank business models and liquidity creation

Using a large panel of US bank holding companies from 2001 to 2015, this study investigates the association between functional diversification and bank liquidity creation. I document evidence of lower liquidity creation for higher diversification. The effect of moving into nontraditional activities on liquidity creation is more apparent with large banks and less pronounced with small banks. The impact of diversification on liquidity creation is less significant during the late stage of crisis and is more clearly observed in small and medium-sized banks. Low liquidity creation banks, leveraged by a higher share of non-interest income, are more likely to further decrease their liquidity creation. The study is of interest to regulators and policymakers who are concerned about bank business models.     

Maximizing an equity portfolio excess growth rate: a new form of smart beta strategy?

It has been claimed that, for dynamic investment strategies, the simple act of rebalancing a portfolio can be a source of additional performance, sometimes referred to as the volatility pumping effect or the diversification bonus because volatility and diversification turn out to be key drivers of the portfolio performance. Stochastic portfolio theory suggests that the portfolio excess growth rate, defined as the difference between the portfolio expected growth rate and the weighted-average expected growth rate of the assets in the portfolio, is an important component of this additional performance (see Fernholz [Stochastic Portfolio Theory, 2002 (Springer)]). In this context, one might wonder whether maximizing a portfolio excess growth rate would lead to an improvement in the portfolio performance or risk-adjusted performance. This paper provides a thorough empirical analysis of the maximization of an equity portfolio excess growth rate in a portfolio construction context for individual stocks. In out-of-sample empirical tests conducted on individual stocks from 4 different regions (US, UK, Eurozone and Japan), we find that portfolios that maximize the excess growth rate are characterized by a strong negative exposure to the low volatility factor and a higher than 1 exposure to the market factor, implying that such portfolios are attractive alternatives to competing smart portfolios in markets where the low volatility anomaly does not hold (e.g. in the UK, or in rising interest rate scenarios) or in bull market environments.