关税减让政策对我国进口的影响

中国加入WTO后,关税减让协议的逐步实行对我国进口贸易产生了极大影响.研究结果表明,关税与我国进口贸易额之间存在着高度的负相关关系,在影响我国进口效应的诸多因素中.关税起到了主要作用,但并非唯一因素.而关税减让在影响我国进口商品结构方面的作用不大.可见,在优化我国进口商品结构方面还需要其他政策措施的辅助与调整.     

Portfolio Optimization under Lower Partial Risk Measures

Portfolio management using lower partial risk (downside risk) measures is attracting more attention of practitioners in recent years. The purpose of this paper is to review important characteristics of these riskmeasures and conduct simulation using four alternative measures, lower semi-variance, lower semi-absolute deviation, first order below targetrisk and conditional value-at-risk.We will show that these risk measures are useful to control downside risk whenthe distribution of assets is non-symmetric. Further, we will propose a computational scheme to resolve the difficultyassociated with solving a large dense linear programming problems resulting from these models. We will demonstrate that this method can in fact solve problems consisting of10⁴ assets and 10⁵ scenarios within a practical amount of CPU time.     

A Multiple and Partial Wavelet Analysis of the Oil Price,Inflation, Exchange Rate,and Economic Growth Nexus in Saudi Arabia

This article provides a fresh insight into the dynamic nexus between oil prices, the Saudi/US dollar exchange rate, inflation, and output growth rate in Saudi Arabia’ economy, using novel Morlet’ wavelet methods. Specifically, it implements various tools of methodology: the continuous wavelet power spectrum, the cross-wavelet power spectrum, the wavelet coherency, the multiple and the partial wavelet coherence to the annual sample period 1969–2014. Our results unveil that the relationships among the variables evolve through time and frequency. From the time-domain view, we show strong but non-homogenous linkages between the four variables. From the frequency-domain view, we uncover significant wavelet coherences and strong lead-lag relationships. From an economic view, the wavelet analysis shows that Saudi economy is still exposed to several global risk factors, which are mainly related to the oil market volatility, and the pegging of the local currency to the US dollar. Such risk factors strongly and negatively affect the real economic growth, exert more pressure on inflation, and substantially limit the freedom to pursue an independent monetary policy.     

锦纶织物在板擦上的应用

对普通板擦的改进,采用锦纶细旦复丝织物为擦拭面,多层网眼织物,紧密净化织物,有利于进行粉尘的收集,锦纶织物在板擦中的应用,提高了板擦的耐磨性,使板擦的使用寿命增加,更科学,更环保。     

Bridging the Gap Between Strategy and Performance: Using Leadership Style to Enable Structural Elements

Successful leaders create structural elements in order to achieve the performance objectives set forth by organizational strategy. Supply chain oriented structural elements are reflected in an organization's relationships, both within the firm and with supply chain partners. In this research effort, we examine how such structural elements can be created as a means through which to enhance performance. Our hypothesized model is rooted in strategy‐structure‐performance theory and integrates elements of servant leadership theory and social exchange theory to explain how building organizational commitment via servant leadership behaviors can ultimately impact performance. We use a survey method to collect data from 158 motor carriers. The results of our structural equation model support our hypotheses and serve to extend the discussion of supply chain structural elements and the role of leadership style in achieving organizational performance.     

Bargaining externalities in a privatization programme

In privatization programmes, the state commonly keeps a minority ownership stake in firms. We provide an explanation based on the externality that privatization of one firm has on the profitability of others. If this externality is negative, as with oligopolistic firms, the government can gain a strategic advantage in bargaining over the sale of one firm if it keeps an ownership share in another. We consider both the simultaneous and the sequential sale of firms. The results apply to the period in which privatization takes place, and are consistent with the delayed sale of minority ownership often observed in practice.     

Reliable Inference in Categorical Regression Analysis for Non‐randomly Coarsened Observations

In most surveys, one is confronted with missing or, more generally, coarse data. Traditional methods dealing with these data require strong, untestable and often doubtful assumptions, for example, coarsening at random. But due to the resulting, potentially severe bias, there is a growing interest in approaches that only include tenable knowledge about the coarsening process, leading to imprecise but reliable results. In this spirit, we study regression analysis with a coarse categorical‐dependent variable and precisely observed categorical covariates. Our (profile) likelihood‐based approach can incorporate weak knowledge about the coarsening process and thus offers a synthesis of traditional methods and cautious strategies refraining from any coarsening assumptions. This also allows a discussion of the uncertainty about the coarsening process, besides sampling uncertainty and model uncertainty. Our procedure is illustrated with data of the panel study ‘Labour market and social security' conducted by the Institute for Employment Research, whose questionnaire design produces coarse data.     

PRICING ASIAN OPTIONS FOR JUMP DIFFUSION

We construct a sequence of functions that uniformly converge (on compact sets) to the price of an Asian option, which is written on a stock whose dynamics follow a jump diffusion. The convergence is exponentially fast. We show that each element in this sequence is the unique classical solution of a parabolic partial differential equation (not an integro‐differential equation). As a result we obtain a fast numerical approximation scheme whose accuracy versus speed characteristics can be controlled. We analyze the performance of our numerical algorithm on several examples.     

发电厂高压开关检测技术

根据高压开关的维修调查报告,高压开关的高故障率导致很多企业正常生产的过程中由于供电的不连续导致巨大的经济损失,通过对高压开关工作原理和状态检修理论的综合分析研究。     

某类高阶偏微分系统离散谱的估计

考虑某类高阶偏微分系统离散谱的估计,利用谱理论、矩阵运算、分部积分、测试函数、Ray—leigh定理和不等式估计等方法,获得了用前n个谱来估计第n＋1个谱的上界的不等式,且其估计系数与区域的几何度量无关,其结论是文献[4—5]的进一步推广．