Use of minimum risk approach in the estimation of regression models with missing observations

This article considers a linear regression model with some missing observations on the response variable and presents two estimators of regression coefficients employing the approach of minimum risk estimation. Small disturbance asymptotic properties of these estimators along with the traditional unbiased estimator are analyzed and conditions, that are easy to check in practice, for the superiority of one estimator over the other are derived. Received May 2001     

From T-Bills to Stocks: Seasonal Anomalies Revisited

This paper employed eleven data series which consist of stocks, bonds, bills, equity premiums, term premiums, and various default premiums to investigate whether January seasonality reported in existing literature is robust across different states of the economy as this has important trading implications. For the periods 1926–1990, small stocks, small stock premiums, low grade bonds, and default premiums (spread between high grade, low grade and government bonds) reveal January seasonality and that the seasonality is robust across different states of the economy except for low grade bond returns and default premiums. January seasonality for low grade bond returns and low grade bond default premiums are primarily driven by results found during periods of economic expansion. Overall, January seasonality is more evident during the economic expansion periods although the magnitude of default premiums is larger during periods of economic contraction. Furthermore, prior findings of strong summer equity returns are primarily driven by the results found during the periods of economic contraction. It is also found that equity returns are generally higher during periods of economic expansion.     

Credit risk and sustainable debt: a model and estimations of why the Euro is stable in the long-run

Sustainable debt has become the key issue in rating of private as well as sovereign debtors. The problem of how to estimate sustainable debt has also been at the center of the debate over the Asian 1997–1998 financial crisis. If the external value of the currency depends on the external debt of a country, it is necessary to estimate the creditworthiness of the country. This paper studies credit risk and sustainable debt in the context of a dynamic model. For a dynamic growth model with an additional equation for the evolution of debt, we demonstrate of how to compute sustainable debt and creditworthiness. The model is estimated by employing time series data for the core countries of the Euro-area. The computations show that the Euro-area has large external assets. Using time series methods, the sustainability of external debt (assets) is estimated for those core countries of the Euro-area. Those estimations show that the Euro will be a stable currency in the long-run.     

高技术企业业绩评价指标体系的五维度框架设计

业绩评价已成为政府、市场和企业普遍关注的现实问题，指标体系是业绩评价的基础，指标体系构建的好坏直接影响到业绩评价的效果。高技术企业业绩的评价应结合高技术企业的特点，构建财务、产品与技术创新、智力资本开发、价值链流程、可持续发展五个维度的评价指标体系。     

医疗服务价格管制与"以药养医"

近年来，我国医疗费用持续上涨，医患关系也变得更加紧张。而针对这些问题所采取的一系列改革措施并没有产生明显的效果，这主要是因为没有充分认识到医疗服务价格管制所带来的严重的负面影响。本文提供了一个用于评价医疗服务价格管制的分析框架。本文的分析表明，医疗服务价格管制会导致“以药养医”体制的形成，而且“以药养医”这一间接定价机制，通常无法使患者的效用水平达到只存在道德风险和有限责任约束时的次优水平。因此，改革目前备受非议的医疗体制，重点在于放松对医疗服务价格的管制。     

Analysing Perceived Downside Risk: the Component Value‐at‐Risk Framework

Multinational companies face increasing risks arising from external risk factors, e.g. exchange rates, interest rates and commodity prices, which they have learned to hedge using derivatives. However, despite increasing disclosure requirements, a firm's net risk profile may not be transparent to shareholders. We develop the ‘Component Value‐at‐Risk (VaR)’ framework for companies to identify the multi‐dimensional downside risk profile as perceived by shareholders. This framework allows for decomposing downside risk into components that are attributable to each of the underlying risk factors. The firm can compare this perceived VaR, including its composition and dynamics, to an internal VaR based on net exposures as it is known to the company. Any differences may lead to surprises at times of earnings announcements and thus constitute a litigation threat to the firm. It may reduce this information asymmetry through targeted communication efforts.     

基于截尾分布理论预测开放式基金大额赎回量

提出了开放式基金的巨额赎回量和大额赎回量的概念，将复合泊阿松分布和截尾分布理论运用在大额赎回量概率计算之中，得到了计算公式。由于开放式基金流动性风险主要来自于大额赎回量，因此使用截尾分布方法预测未来近期的大额赎回量更合适。推导出了正态分布下大额赎回量的期望和方差计算公式。为基金管理人合理规避这种流动性风险提供了一种预测方法。     

DEFAULT RISK AND DIVERSIFICATION: THEORY AND EMPIRICAL IMPLICATIONS

Recent advances in the theory of credit risk allow the use of standard term structure machinery for default risk modeling and estimation. The empirical literature in this area often interprets the drift adjustments of the default intensity's diffusion state variables as the only default risk premium. We show that this interpretation implies a restriction on the form of possible default risk premia, which can be justified through exact and approximate notions of "diversifiable default risk." The equivalence between the empirical and martingale default intensities that follows from diversifiable default risk greatly facilitates the pricing and management of credit risk. We emphasize that this is not an equivalence in distribution, and illustrate its importance using credit spread dynamics estimated in Duffee (1999) . We also argue that the assumption of diversifiability is implicitly used in certain existing models of mortgage-backed securities.     

引起承包商成本超额的不可抗力风险因素研究

本文介绍了引起承包商成本超额的不可抗力风险因素，并对此进行具体分析，指出了各风险因素与成本超额的关系，为承包商进行风险控制了理论指导。