Time diversification and security preferences: A stochastic dominance analysis

We use stochastic dominance to test whether investor should prefer riskier securities as the investment horizon lengthens. Return distributions for stocks, bonds, and U.S. Treasury bills are generated for holding periods of one to 25 years by simulation. For each holding period, stochastic dominance tests are run to establish preferences between the alternative security classes. Contrary to previous mean-variance based studies, we find no evidence that high-risk securities (stocks) dominate low-risk securities (bonds, Treasury bills) as the investment horizon lengthens. However, we do find that corporate bonds systematically dominate government bonds.     

资产周期特性与保险公司资产配置策略

在竞争激烈的保险市场上,作为盈利的两大支柱之一,保险公司资产管理的能力日趋重要,而保险公司资产配置是保险资产管理的核心,其研究意义就显得尤为重要。本文首先给出保险资产配置的意义与总体原则,然后从保险资金的来源和特性入手,在详细分析了美国、中国不同经济周期和市场周期下大类资产风险收益特性的基础之上,给出保险公司资产负债管理和资产配置的战略决策建议。     

Pricing the Credit Risk of Secured Debt and Financial Leasing

Abstract:  This paper presents closed form solutions to price secured bank loans and financial leases subject to default risk. Secured debt fair credit spreads always increase in the debtor's default probability, whereas financial leasing fair credit spreads may well decrease in the lessee's default probability and even be negative. The reason is that the lessor, unlike the secured lender, can gain from the lessee's default, especially when the leasing contract envisages initial prepayments or the lessee's terminal options to either purchase the leased asset or to extend the lease maturity. This result, which critically depends on contractual and bankruptcy code provisions, can explain some of the empirical evidence and the use of financial leases as an alternative to secured bank lending to finance small, risky and relatively opaque firms.     

Regression-based Monte Carlo methods for stochastic control models: variable annuities with lifelong guarantees

We present regression-based Monte Carlo simulation algorithm for solving the stochastic control models associated with pricing and hedging of the guaranteed lifelong withdrawal benefit (GLWB) in variable annuities, where the dynamics of the underlying fund value is assumed to evolve according to the stochastic volatility model. The GLWB offers a lifelong withdrawal benefit, even when the policy account value becomes zero, while the policyholder remains alive. Upon death, the remaining account value will be paid to the beneficiary as a death benefit. The bang-bang control strategy analysed under the assumption of maximization of the policyholder’s expected cash flow reduces the strategy space of optimal withdrawal policies to three choices: zero withdrawal, withdrawal at the contractual amount or complete surrender. The impact on the GLWB value under various withdrawal behaviours of the policyholder is examined. We also analyse the pricing properties of GLWB subject to different model parameter values and structural features.     

波动率风险及风险价格——来自中国A股市场的证据

本文应用Fama-Macbeth估计方法,以1997年2月至2009年6月中国A股股票为样本,考察股票市场波动率风险及其风险价格的特征。研究表明:波动率风险是一个显著的横截面定价因子,其风险价格为负,该结论不受流动性及市场偏度因子、待检资产改变、波动率模型设定的影响;在资产定价模型中引入波动率风险因子有利于解释规模效应和账面市值比效应异象。波动率的风险因子可以涵盖部分宏观经济变量的定价信息,规模因子是波动率风险因子的代理变量。     

制造业企业信贷风险压力测试研究--基于现金流的蒙特卡洛模拟方法

基于现金流的蒙特卡洛模拟方法,提出了一个制造业企业信贷风险压力测试的分析方法和框架。通过财务指标的计算,经营活动净现金流可以通过存货、应收账款、应付账款、产品价格、产品销量、生产成本以及周转率等会计科目进行表示,而企业经营活动净现金流是否为负可以作为判定制造业企业违约的标准。然后,在情景假设和随机变量估计的基础上,可以通过蒙特卡洛模拟计算违约概率。同时,利用企业的经营和财务数据进行了模拟测试。在金融机构的风险管理应用中,可以根据测试企业的具体情况对变量进行合理的设定,进而将研究提出的分析框架应用到不同的企业。     

Credit Risk and the Term Structure of Lease Rates: A Reduced Form Approach

Previous research either assumes default free leases or leases subject to default risk using a structural approach. However, structural credit risk models suffer from a common criticism that the firm’s asset value process is unobservable. We develop a reduced form credit risk model for leases that avoids making assumptions regarding unobservable asset valuation processes. Furthermore, we assume a correlated market and credit risk that provides us with a simple analytic formula for valuing defaultable lease contracts. Numerical analysis reveals that tenant credit risk can have a substantial impact on the term structure of leases. Finally, we use the model to demonstrate the implied lease term structure for a set of retail and financial firms in the Fall of 2000.

European asset swap spreads and the credit crisis

We examine time-varying behaviour and determinants of asset swap (ASW) spreads for 23 iBoxx European corporate bond indexes from January 2006 to January 2009. The results of a Markov switching model suggest that ASW spreads exhibit regime-dependent behaviour. The evidence is particularly strong for Financial and Corporates Subordinated indexes. Stock market volatility determines ASW spread changes in turbulent periods, whereas stock returns tend to affect spread changes in calm periods. While market liquidity affects spreads only in turbulent regimes the level of interest rates is an important determinant of spread changes in both regimes. Finally, we identify stock returns, lagged ASW spread levels, and lagged volatility of ASW spreads as major drivers of the regime shifts. The results are robust in the extended sample (January 2006 to October 2013) that includes a post-crisis period.     

Accounting data and asset valuation: Theory

Firms and divisions which are not traded on organized exchanges are often valued without the benefit of market data. Accounting data is used instead. One suggested approach is to use accounting beta as a proxy for market return beta. In the context of the Arbitrage Pricing Theory, we provide a theoretical justification for such a procedure. Our results provide a set of sufficient conditions so that return betas and accounting betas are equal. Our results also suggest a general methodology for evaluating projects and untraded firms using accounting data. The method underlying the derivation here is very general and can be applied in deriving testable restrictions between fundamentals, broader in context than that of accounting variables.     

Timing and diversification: A state-dependent asset allocation approach

Abstract

The influence of changing economic environment leads the distribution of stock market returns to be time-varying. A conditionally optimal investment hence requires a dynamic adjustment of asset allocation. In this context, this paper examines the improvement in portfolio performance by simulating portfolio strategies that are conditioned on the Markov regime switching behaviour of stock market returns. Including a memory effect eliminates the empirical shortcoming of discrete state models, namely that they produce a standard and an extreme state in stock returns. So far, this has prevented the regimes from being used as a valuable conditioning variable. Based on a discrete state indicator variable, is presented evidence of considerable performance improvement relative to the static model due to optimal shifting between aggressive and well diversified portfolio structures.     

Economic Risk Factors and Commercial Real Estate Returns

A great deal of research has focused on the links between stock and bond market returns and macroeconomic events such as fluctuations in interest rates, inflation rates, and industrial production. Although the comovements of real estate and other asset prices suggests that these same systematic risk factors are likely to be priced in real estate markets, no study has formally addressed this issue. This study identifies the growth rate in real per capita consumption, the real T-bill rate, the term structure of interest rates, and unexpected inflation as fundamental drivers or state variables that systematically affect real estate returns. The finding of a consistently significant risk premium on consumption has important ramifications for the vast literature that has examined the (risk-adjusted) performance of real estate, for it suggests that prior findings of significant abnormal returns (either positive or negative) that have ignored consumption are potentially biased by an omitted variables problem. The results also have important implications for dynamic asset allocation strategies that involve the predictability of real estate returns using economic data.     

Cash management using multi-stage stochastic programming

We consider a cash management problem where a company with a given financial endowment and given future cash flows minimizes the Conditional Value at Risk of final wealth using a lower bound for the expected terminal wealth. We formulate the optimization problem as a multi-stage stochastic linear program (SLP). The company can choose between a riskless asset (cash), several default- and option-free bonds, and an equity investment, and rebalances the portfolio at every stage. The uncertainty faced by the company is reflected in the development of interest rates and equity returns. Our model has two new features compared to the existing literature, which uses no-arbitrage interest rate models for the scenario generation. First, we explicitly estimate a function for the market price of risk and change the underlying probability measure. Second, we simulate scenarios for equity returns with moment-matching by an extension of the interest rate scenario tree.     

A general framework for the derivation of asset price bounds: an application to stochastic volatility option models

We present a generalization of Cochrane and Saá-Requejo’s good-deal bounds which allows to include in a flexible way the implications of a given stochastic discount factor model. Furthermore, a useful application to stochastic volatility models of option pricing is provided where closed-form solutions for the bounds are obtained. A calibration exercise demonstrates that our benchmark good-deal pricing results in much tighter bounds. Finally, a discussion of methodological and economic issues is also provided.      

外资银行资产风险集中度监管比较研究及启示

资产风险集中度是各国外资银行审慎监管制度体系顺利运行的前提与基础，在对比各国银行法中有关外资银行资产集中度的监管规定基础上，应从以下几方面完善我国现有监管制度体系，一是根据法律地位的不同，在与母国签订双边监管合作协议的框架下，对外资银行子行、合资银行和分行提出不同的监管资本充足率要求；二是以全面风险管理流程为基础，增强现有监管制度的弹性和有效性；三是建立大额风险敞口定期报告及预警机制。     

基于银行同业网络与资产重叠的金融风险传染研究

本文分析当银行遭受不同类型初始冲击时,传染概率、传染范围、损失程度随资产多样化程度、初始冲击程度变化的分布情况。研究表明,在两类传染途径共同作用下,资产多样化程度和初始冲击程度很低时风险传染概率与范围仍呈现较高水平,资产多样化程度较高时风险传染概率与范围呈现较低水平;不同网络结构中资产多样化对于初始冲击具有不同的吸收能力,且传染范围呈现出明显的由稳定转向非稳定的相变过程;在传染范围稳定的区域,损失程度仍随资产多样化程度的增加而增大。     

保费收入随机化条件下的保险公司破产概率模型研究

保费收入是保险公司破产概率的重要影响因素。传统的保险公司破产概率模型常将保费收入过程看作连续的确定性过程,然而在现实中,保费收入过程却是一个离散的随机过程。本文用复合泊松过程描述保费收入,从而将确定性保费收入条件下的破产概率模型拓展到随机化保费收入条件下的破产概率模型,在此基础上模拟计算了保险公司破产概率,并比较分析了不同的保险资金投资模式对破产概率的影响。     

REIT Risk Premium Sensitivity and Interest Rates

This analysis investigates several aspects of the relationship between daily REIT stock risk premiums and various interest rates. Consistent with prior research, the general findings indicate that interest rates do impact REIT returns. This study specifically finds that stock returns are more sensitive to maturity rate spread between short- and long-term treasuries than the credit rate spread between commercial bonds and treasuries. In addition, the analyses document a structural model shift during the nineties that has made REITs more sensitive to credit risk. In additional to change in investor clientele, an analysis of declining REIT credit-worthiness points to a root cause for this shift.     

Economic interdependence and common stochastic trends: A comparative analysis between EMU and non-EMU stock markets

Whether economic interdependence among countries is a contributing factor to cointegration and common stochastic trends in international stock markets is indiscernible due to contradictory results from prior empirical work. This study aims to add clarity to this issue through a more distinct grouping of countries and methodological enhancements. A comparative analysis of cointegration is conducted between stock market price indices of major Economic and Monetary Union (EMU) and non-EMU countries. The conventional Johansen methodology is augmented with several diagnostic techniques (that have not been all inclusive in previous studies) to ensure the robustness of test results. Major findings pertinent to investors and policymakers are that economic interdependence appears to be the important contributing factor and that the U.S. stock market does not exert influences on long-run performances of other included stock markets. Furthermore, while the UK is not an EMU member, it may be viewed as a quasi EMU participant due to its stock market being cointegrated with and yet one of the common stochastic trends (besides those of Germany, Italy, and the Netherlands) within the EMU stock markets under investigation.     

Optimal Estimation of the Risk Premium for the Long Run and Asset Allocation: A Case of Compounded Estimation Risk

It is well known that an unbiased forecast of the terminal valueof a portfolio requires compounding at the arithmetic mean returnover the investment horizon. However, the maximum-likelihoodpractice, common with academics, of compounding at the estimatorof mean return results in upward biased and highly inefficientestimates of long-term expected returns. We derive analyticallyboth an unbiased and a small-sample efficient estimator of long-termexpected returns for a given sample size and horizon. Both estimatorsentail penalties that reduce the annual compounding rate asthe investment horizon increases. The unbiased estimator, whichis far lower than the compounded arithmetic average, is stillvery inefficient, often more so than a simple geometric estimatorknown to practitioners. Our small-sample efficient estimatoris even lower. These results compound the sobering evidencein recent work that the equity risk premium is lower than suggestedby post-1926 data. Our methodology and results are robust toextensions such as predictable returns. We also confirm analyticallythat parameter uncertainty, properly incorporated, producesoptimal asset allocations, in stark contrast to conventionalwisdom. Longer investment horizons require lower, not higher,allocations to risky assets.     

Forecasting variance using stochastic volatility and GARCH

This paper estimates the conditional variance of daily Swedish OMX-index returns with stochastic volatility (SV) models and GARCH models and evaluates the in-sample performance as well as the out-of-sample forecasting ability of the models. Asymmetric as well as weekend/holiday effects are allowed for in the variance, and the assumption that errors are Gaussian is released. Evidence is found of a leverage effect and of higher variance during weekends. In both in-sample and out-of-sample comparisons SV models outperform GARCH models. However, while asymmetry, weekend/holiday effects and non-Gaussian errors are important for the in-sample fit, it is found that these factors do not contribute to enhancing the forecasting ability of the SV models.