政府规制低碳经济发展的分析与思考

政府规制与发展低碳经济有着密切的联系。文章研究并总结了发达国家发展低碳经济的成功的经验与做法，从战略规划、法律法规、激励与约束政策、技术创新、舆论引导等角度探讨了中国发展低碳经济的战略对策，重点从制定基于区域经非均衡的碳减排规划、法律法规体系应关注延伸生产者责任、通过税收和补贴增加低碳产品供给、技术创新中政府必须保护创新企业的竞争优势和垄断红利、依托非政府组织引导低碳消费并构建低碳经济利益相关体系等方面提出了对策建议。     

Promotion Time Cure Rate Model with Bivariate Random Effects

In this article, we consider the inclusion of random effects in both the survival function for at-risk subjects and the cure probability assuming a bivariate normal distribution for those effects in each cluster. For parameter estimation, we implemented the restricted maximum likelihood (REML) approach. We consider Weibull and Piecewise Exponential distributions to model the survival function for non-cured individuals. Simulation studies are performed, and based on a real database we evaluate the performance of our proposed model. Effect of different follow-up times and the effect of considering independent random effects instead of bivariate random effects are also studied.     

20世纪90年代末中国各民族人口的死亡水平

本文根据第五次人口普查资料,及各民族不同的人口规模,提出了计算年龄组死亡率的不同方法,由此得到了各民族在20世纪90年代末关于人口死亡的指标。计算结果显示,从总体上说,中国各民族与10年前相比,死亡力有所下降,但也存在着一些不容忽视的现象,如女性婴儿死亡率高于男性的民族数增加,一些民族至今还保持着较高的死亡力。另外,对死亡变化出现异常的情况,本文从死亡的随机误差作了一定的解释。     

Who speaks up to whom? A relational approach to employee voice

We adopt a relational approach to examine the effects of social relations and formal structure on who speaks up to whom about problems at work. Data were collected in a two-wave employee survey in three Dutch preschools. Using exponential random graph modeling, we found significant positive effects of formal structure (recipient's hierarchical level; team co-membership) and good relations between speaker and recipient on the likelihood of voice in a dyad. Speaker's hierarchical level had positive effects, significant in Wave 1. Speaker's degree centrality significantly reduced the likelihood of voice, whereas recipient's degree centrality had no effect.     

The local and global structure of knowledge production in an emergent research field: An exponential random graph analysis

Previous research has characterized knowledge networks by diffuse connectivity and/or clusters and the absence of centrality. In contrast, exponential random graph models used in this article demonstrate that the uncertainty and centralized influence typical of an emerging area of research leads to the creation of a densely interconnecting core that acts to cohere the network. Moreover, eclecticism and innovativeness, also characteristic of a developing area, lead to a diffusely connected structure. The data, comprising 2200 authors and 76 papers have been manually coded from articles on the feminization of the labor force in Asia.     

Linear Regression for Panel With Unknown Number of Factors as Interactive Fixed Effects

In this paper, we study the least squares (LS) estimator in a linear panel regression model with unknown number of factors appearing as interactive fixed effects. Assuming that the number of factors used in estimation is larger than the true number of factors in the data, we establish the limiting distribution of the LS estimator for the regression coefficients as the number of time periods and the number of cross‐sectional units jointly go to infinity. The main result of the paper is that under certain assumptions, the limiting distribution of the LS estimator is independent of the number of factors used in the estimation as long as this number is not underestimated. The important practical implication of this result is that for inference on the regression coefficients, one does not necessarily need to estimate the number of interactive fixed effects consistently.     

A Note on “Sourcing Decisions with Stochastic Supplier Reliability and Stochastic Demand”

This note complements the study of Burke, Carillo, and Vakharia ( 2009 hereafter “BCV”) which analyzes a class of single‐product multisourcing problems under stochastic demand and random yields. The purpose is twofold. First, we prove that the objective function used by these authors is only a lower bound for the expected profit for which we provide the correct expression. Second, we show on some of the numerical instances provided in BCV's study that the structure and the performance of the BCV ordering policy may be substantially different from the optimal ordering policy. We conclude by giving general qualitative insights characterizing suboptimality of the BCV solution.     

Optimal Policies for Perishable Products When Transportation to Export Market Is Disrupted

We consider a problem where a firm produces a variety of fresh products to supply two markets: an export market and a local market. A public transportation service is utilized to deliver the products to the export market, which is cheap, but its schedule is often disrupted severely. Each time this happens, the firm faces the following questions. (i) For a product that has been finished and is waiting for delivery to the export market, should it continue to wait, at an increasing risk of decay, and when should the waiting be terminated and the product be put to the local market? (ii) For a product that has not been finished, should its processing be postponed, so as to reduce the loss from decay after its completion? (iii) What is the best sequence to process the remaining products, according to the information available? We develop, in this study, a model to address these and other related questions. We find optimal policies that minimize the total expected loss in both the make‐to‐order and make‐to‐stock production systems, respectively. For each finished product, we reveal relationships among the desirable waiting time, the price at the local market, and the decaying cost. For unfinished products, we find the optimal start times and processing sequence. Numerical experiments are also conducted to evaluate the optimal policies.     

DEA as a tool for predicting corporate failure and success: A case of bankruptcy assessment

Using an additive super-efficiency data envelopment analysis (DEA) model, this paper develops a new assessment index based on two frontiers for predicting corporate failure and success. The proposed approach is applied to a random sample of 1001 firms, which is composed of 50 large US bankrupt firms randomly selected from Altman's bankruptcy database and 901 healthy matching firms. This sample represents the largest firms that went bankrupt over the period 1991–2004 and represents a full spectrum of industries. Our findings demonstrate that the DEA model is relatively weak in predicting corporate failures compared to healthy firm predictions, and the assessment index improves this weakness by giving the decision maker various options to achieve different precision levels of bankrupt, non-bankrupt, and total predictions.     

高压容器结构不连续区域的随机有限元分析

利用二阶矩法推导出圆柱壳和球壳基于弹性失效设计准则的中径公式的可靠度指标计算公式,并将其应用于一算例中。在此可靠性设计基础上建一圆柱壳和半球形封头连接的高压容器模型,然后利用ANSYS软件对其进行随机有限元分析,求出圆柱筒体与封头连接区的可靠度。结果表明:高压容器中圆柱筒体与封头连接区的可靠度远低于半球形封头与圆柱形筒体的可靠度。本文对输出的功能函数进行的灵敏度分析,可为结构参数的优化设计提供参考。