“汶川地震”的证券市场板块效应研究

本文采用事件研究法分别研究了汶川地震对我国金融板块和四川板块的影响。本文根据汶川地震的特点确定了估计窗和事件窗,选择市场模型作为正常收益的估计模型,得到了各个板块在事件窗内的累积非正常收益并对其进行了显著性检验。本文研究结果表明:汶川地震对我国金融板块没有显著性影响;汶川地震对我国四川板块的影响是四川板块组合的累积非正常收益由显著为正到显著为负的变化过程。     

Quantifying and characterising aviation accident risk factors

This paper compares the exposure of normal flights to a number of meteorological factors that also exist for flights resulting in accidents. The factors examined include visibility, ceiling height, temperature, crosswind, tailwind and instrument or visual meteorological conditions. Differences in exposure to these factors are examined and a measure of accident propensity related to different levels of risk exposure is quantified based on relative accident involvement ratios. Four categories of aircraft accidents relevant to the assessment of airport safety areas are examined.     

Implicit expectiles and measures of implied volatility

It is well known that the normal distribution is inadequate in capturing the skewed and heavy-tailed behaviour of exchange rate returns. To this end, various flexible distributions that are capable of modelling the asymmetric and tailed behaviour of returns have been proposed. In this paper, we investigate the performance of the generalized lambda distribution (GLD) to capture the skewed and leptokurtic behaviour of exchange rate returns. We do this by conducting a comprehensive numerical study to compare the performance of the GLD against the performances of the skewed t distribution, the unbounded Johnson family of distributions and the normal inverse Gaussian (NIG) distribution. Our results suggest that in terms of the value-at-risk and expected shortfall, the GLD shows at least similar performance to the skewed t distribution and the NIG distribution. Considering the ease in GLD’s use for random variate generation in Monte Carlo simulations, we conclude that the GLD can be a good alternative in various financial applications where modelling of the heavy tail behaviour is critical.     

新常态下农业技术推广体系悬浮与多轨发展研究

新常态下,中国农业技术推广体系面临悬浮困境。通过全国10个省区调研数据,挖掘农技推广体系呈现的新问题,进一步抽象悬浮现状表征并剖析其生发机理。提出构建以市场机制为基础、多轨并行的现代农业技术推广体系,以促进现代新农业、新农民、新农村可持续发展。     

Modeling regime‐dependent agricultural commodity price volatilities

In stark contrast to financial markets, relatively little attention has been given to modeling agricultural commodity price volatility. In recent years, numerous methodologies with various strengths have been proposed for modeling price volatility in financial markets. We propose using a mixture of normals with unique GARCH processes in each component for modeling agricultural commodity prices. While a normal mixture model is quite flexible and allows for time varying skewness and kurtosis, its biggest strength is that each component can be viewed as a different market regime and thus estimated parameters are more readily interpreted. We apply the proposed model to ten different agricultural commodity weekly cash prices. Both in‐sample fit and out‐of‐sample forecasting tests confirm that the two‐state NM‐GARCH approach performs better than the traditional normal GARCH model. A significant and state‐dependent inverse leverage effect is detected only for pork in the regime where the price is expected to drop, indicating the volatility in this regime tends to increase more following a realized price rise than a realized price drop.     

Financial profiles and the disclosure of expenditures for socially responsible purposes

Recently the relationship between “socially responsible” activities and the financial performance of corporations has received attention in the business literature. Most studies have focused on the market reaction of shareholders to the disclosure of both monetary and nonmonetary corporate contributions relating to pollution control, employee welfare, affirmative action, and other activities deemed to be in the public interest. Results of this research have been mixed, with some authors finding favorable market response to socially responsible actions, and others finding no difference between the market performance of more and less responsible firms. The purpose of this paper is to examine financial performance and socially responsible activities from a different perspective. Specifically, it examines the relationship between the disclosure of monetary expenditures for various social initiatives and composite financial accounting profiles of disclosing and nondisclosing firms. Using two-group discriminant analysis, the authors conclude that management tends to disclose monetary expenditures for these generally nonproductive purposes at times when the financial statements of the firm otherwise look favorable to shareholders. Such disclosure in a sample of Fortune 500 firms in 1976 and 1977 was clearly not unrelated to financial performance, and neither did it appear to occur in order to explain relatively poor financial statements.     

Robust testing procedures of process locations

In many manufacturing and service industries, the quality department of the organization works continuously to ensure that the mean or location of the process is close to the target value. In order to understand the process, it is necessary to provide numerical statements of the processes that are being investigated. That is why the researcher needs to check the validity of the hypotheses that are concerned with some physical phenomena. It is usually assumed that the collected data behave well. However, sometimes the data may contain outliers. The presence of one or more outliers might seriously distort the statistical inference. Since the sample mean is very sensitive to outliers, this research will use the smooth adaptive (SA) estimator to estimate the population mean. The SA estimator will be used to construct testing procedures, called smooth adaptive test (SA test), for testing various null hypotheses. A Monte Carlo study is used to simulate the values of the probability of a Type I error and the power of the SA test. This is accomplished by constructing confidence intervals of the process mean by using the SA estimator and bootstrap methods. The SA test will be compared with other tests such as the normal test, t test and a nonparametric statistical method, namely, the Wilcoxon signed-rank test. Also, the cases with and without outliers will be considered. For the right-skewed distributions, the SA test is the best choice. When the population is a right-skewed distribution with one outlier, the SA test controls the probability of a Type I error better than other tests and is recommended.     

Financial frictions and the futures pricing puzzle

In perfect capital markets, the futures price of an asset should be an unbiased forecast of its realized spot price when the contract matures. In reality, futures prices are often higher for some assets and lower for others. However, there is no stability in the relationship between futures prices and the realized spot prices. This instability has been a puzzle in the existing financial literature. The key to this puzzle may lie in the nature of the model and the lack of market imperfections. In this study, we take a theoretical approach in a dynamic multi-period environment. We incorporate competition between disparate economic agents and impose financial frictions (i.e., imperfections) that are in the form of hedging and borrowing limits on them. Our model gives rise to multiple equilibria, each with unique market clearing prices, with the market switching between these equilibria. Our analysis incorporates a comprehensive consideration of the risks faced by the futures markets participants (i.e., speculators and hedgers) and leads to a better understanding of the puzzle.     

The environmental improvement under China’s ‘New Normal’

ABSTRACT

The significant environmental improvement in China has drawn much research attention in recent years. However, in exploring the factors that lead to pollution reduction, most literature has ignored the slowing economic growth under the ‘New Normal’ of China. This omission could lead to the overestimation of the pollution reduction effects of other factors. In this paper, we estimate the effect of the economic slowdown using a dynamic Computable General Equilibrium model, CHINAGEM. We find that the contribution of the economic slowdown to pollution reduction ranges from 10% to 30%. This indicates the importance of considering the economic slowdown when evaluating the effects of other factors related to the environmental improvement in China.