地区专业化的度量

在封闭经济假设和地区间需求结构一致假设下,本文构造了地区专业化的度量指标——地区专业化系数;这一度量指标更具一般性,产业结构差异系数、空间分布差异系数、绝对利差及行业分工指数等指标只是作为它的特例而存在。在讨论地区专业化问题时,如果忽略地区的(或行业的)相对规模因素,除了犯有逻辑推理错误外,在实践中还存在着可能得出错误判断的倾向。本文发现:中国工业的地区专业化水平自20世纪80年代中后期以来有了较大程度的提高;如果忽略地区的(或行业的)相对规模因素来讨论中国工业的地区专业化问题,则会高估中国工业的地区专业化水平。     

上市公司可持续发展评价体系构建

目前,我国上市公司业绩评价体系门类繁多,但专门评价可持续发展能力的指标体系尚停留在探索阶段。本文在现有研究基础上,构建了上市公司可持续发展的实现模型,并选取定量指标,采用变异系数总指数法赋予权重,建立了上市公司可持续发展评价体系。以2003年我国电子行业上市公司为样本进行检验,结果发现,其结果与《2003年度中国上市公司业绩评价报告》具有一致性。     

小企业会计制度与税务制度差异研究

由于企业会计制度与税务制度所规范的对象和目的不同,会计核算和税务核算之间始终存在着一定的差异。小企业会计制度在会计核算原则、会计假设、会计方法、会计政策及会计实务等方面都与现行的税务制度存在着较大的差异,而这些差异会导致国家税源的流失,造成纳税调整增多,并容易引起征纳双方的纠纷,甚至不能正确地确认纳税人权益,也给企业避税创造了机会。本文建议,应加快我国税收制度的改革,减少小企业会计制度与税务制度的差异,确保小企业会计核算的准确性,并能依法纳税。     

Testing for unit roots in time series models with non-stationary volatility

Many of the key macro-economic and financial variables in developed economies are characterized by permanent volatility shifts. It is known that conventional unit root tests are potentially unreliable in the presence of such behaviour, depending on a particular function (the variance profile) of the underlying volatility process. Somewhat surprisingly then, very little work has been undertaken to develop unit root tests which are robust to the presence of permanent volatility shifts. In this paper we fill this gap in the literature by proposing tests which are valid in the presence of a quite general class of permanent variance changes which includes single and multiple (abrupt and smooth-transition) volatility change processes as special cases. Our solution uses numerical methods to simulate the asymptotic null distribution of the statistics based on a consistent estimate of the variance profile which we also develop. The practitioner is not required to specify a parametric model for volatility. An empirical illustration using producer price inflation series from the Stock–Watson database is reported.     

Restricted maximum likelihood estimation under Eisenhart model Ill

For a balanced two-way mixed model, the maximum likelihood (ML) and restricted ML (REML) estimators of the variance components were obtained and compared under the non-negativity requirements of the variance components by L ee and K apadia (1984). In this note, for a mixed (random blocks) incomplete block model, explicit forms for the REML estimators of variance components are obtained. They are always non-negative and have smaller mean squared error (MSE) than the analysis of variance (AOV) estimators. The asymptotic sampling variances of the maximum likelihood (ML) estimators and the REML estimators are compared and the balanced incomplete block design (BIBD) is considered as a special case. The ML estimators are shown to have smaller asymptotic variances than the REML estimators, but a numerical result in the randomized complete block design (RCBD) demonstrated that the performances of the REML and ML estimators are not much different in the MSE sense.     

欧盟REACH法令对中国化工产品出口的影响分析

欧盟REACH法令的实施将促进我国化学工业的发展,但在短期内会导致我国出口欧盟化工产品和进口化工产品成本上升,降低出口产品竞争力,部分产品甚至退出欧盟市场,其他国家可能纷纷效仿欧盟,引起连锁反应。应对该种技术性壁垒,我国政府和行业协会应加大宣传REACH法令的力度,加快国内相关立法,推进国内实验室的GLP认证工作。另外,化学品生产企业应提高自身产品质量,做好化学品注册的可行性分析和预注册工作。     

中国饲料工业期货的价格发现实证研究

本文借助向量自回归模型、协整检验、误差修正模型、方差分解、脉冲响应函数等方法,以中国唯一的饲料工业期货———大连商品交易所豆粕期货品种为例,研究了期货价格与现货价格之间的动态关系,定量刻画了期货市场在价格发现中的作用。研究结果显示:豆粕期货价格与现货价格存在相互引导关系,并且期货与现货价格之间存在长期均衡关系,对豆粕期货来说,期货市场在价格发现功能中起到主导作用。     

The market price of risk of the variance term structure

In this paper I examine the market price of risk of the variance term structure. To this end, the S&P 500 option implied variance term structure is used as a proxy for aggregate variance risk. Principal component analysis shows that time variation in the variance term structure over the 1996–2012 period can be explained mainly by two factors which capture changes in the level and slope. The market price of risk of each factor is estimated in the cross-section of stock returns. The slope of the variance term structure is the most significant factor in the cross-section of stocks returns and carries a negative risk premium. The slope factor has also some predictive ability over long horizon equity returns.     

Variance swaps valuation under non-affine GARCH models and their diffusion limits

In this article, we investigate the pricing and convergence of general non-affine non-Gaussian GARCH-based discretely sampled variance swaps. Explicit solutions for fair strike prices under two different sampling schemes are derived using the extended Girsanov principle as the pricing kernel candidate. Following standard assumptions on time-varying GARCH parameters, we show that these quantities converge respectively to fair strikes of discretely and continuously sampled variance swaps that are constructed based on the weak diffusion limit of the underlying GARCH model. An empirical study which relies on a joint estimation using both historical returns and VIX data indicates that an asymmetric heavier tailed distribution is more appropriate for modelling the GARCH innovations. Finally, we provide several numerical exercises to support our theoretical convergence results in which we further investigate the effect of the quadratic variation approximation for the realized variance, as well as the impact of discrete versus continuous-time modelling of asset returns.     

How does the market variance risk premium vary over time? Evidence from S&P 500 variance swap investment returns

We explore whether the market variance risk premium (VRP) can be predicted. We measure VRP by distinguishing the investment horizon from the variance swap’s maturity. We extract VRP from actual S&P 500 variance swap quotes and we test four classes of predictive models. We find that the best performing model is the one that conditions on trading activity. This relation is also economically significant. Volatility trading strategies which condition on trading activity outperform popular benchmark strategies, even once we consider transaction costs. Our finding implies that broker dealers command a greater VRP to continue holding short positions in index options in the case where trading conditions deteriorate.