论环境影响评价与排污许可制度的互动和衔接——从制度逻辑和构造建议的角度

如何将环境影响评价与排污许可等环境治理工具进行互动与衔接是未来环境治理制度改革的关键。两种制度在现时的环境下都存在各自的问题及相应的变革路径。两种不同的变革路径却有着共同的价值需求，即环境影响评价与排污许可的衔接与互动。在衔接的过程中存在的最大的争议就是维持或简化环境影响评价审批，这种衔接思路的差异制造了两种截然相反的制度逻辑:一种以维持环评审批为核心，另一种以简化环评审批为核心。就中国目前的环境影响评价制度改革方向而言，简化环评审批似乎已是不可阻挡之潮流。是否应当以简化环评审批、强调排污许可为目标进行两种制度的衔接。简化环评审批并不等同于弱化环评制度；在环境影响评价与排污许可的衔接构造上，应当遵循的思路:在宏观上，以效益最大化统领全局；在具体操作上，秉持“在简化环境影响评价的大环境中，寻找强化的契机；以排污许可为核心的进程中，夯实衔接的构造”的理念。     

Trade sophistication in developing countries: Does export destination matter?

We investigate whether exports to developed economies stimulate export sophistication (represented by UNCTAD’s index of export similarity) in developing countries. Results from fixed-effects estimations suggest that exporting to developed economies enhances the sophistication of exports in the exporting country but there are diminishing returns to this effect. We also find non-linear effects from FDI and income on export sophistication with the effect of income exhibiting diminishing returns which suggests that the gains from exporting to developed economies are higher for lower-income countries; i.e., as income increases, the gains taper off. We discuss the policy implications of these results.     

Analysis of a two incongruent arrivals and services M/G/1 queue with random feedback

A queuing system with two incongruent arrivals and services is considered. Two kinds of customers enter the system by Poisson process and the service times are assumed to have general distribution. After first kind service completion, it may feedback to repeat the first service, leave the system or go to give second service. The same policy is applied for the other kind of customer. All stochastic processes involved in this system are independent. We derive the probability generating function for each kind and for the system that yield the performance measures. Some numerical approaches examined the validity of the results.     

Assessing additivity in nonparametric models —A kernel‐based method

In this article, we address the testing problem for additivity in nonparametric regression models. We develop a kernel‐based consistent test of a hypothesis of additivity in nonparametric regression, and establish its asymptotic distribution under a sequence of local alternatives. Compared to other existing kernel‐based tests, the proposed test is shown to effectively ameliorate the influence from estimation bias of the additive component of the nonparametric regression, and hence increase its efficiency. Most importantly, it avoids the tuning difficulties by using estimation‐based optimal criteria, while there is no direct tuning strategy for other existing kernel‐based testing methods. We discuss the usage of the new test and give numerical examples to demonstrate the practical performance of the test. The Canadian Journal of Statistics 39: 632–655; 2011. © 2011 Statistical Society of Canada     

Two‐sample empirical likelihood ratio tests for medians in application to biomarker evaluations

The median is a commonly used parameter to characterize biomarker data. In particular, with two vastly different underlying distributions, comparing medians provides different information than comparing means; however, very few tests for medians are available. We propose a series of two‐sample median‐specific tests using empirical likelihood methodology and investigate their properties. We present the technical details of incorporating the relevant constraints into the empirical likelihood function for in‐depth median testing. An extensive Monte Carlo study shows that the proposed tests have excellent operating characteristics even under unfavourable occasions such as non‐exchangeability under the null hypothesis. We apply the proposed methods to analyze biomarker data from Western blot analysis to compare normal cells with bronchial epithelial cells from a case–control study. The Canadian Journal of Statistics 39: 671–689; 2011. © 2011 Statistical Society of Canada     

Testing the monotonicity or convexity of a function using regression splines

Methods for smoothed isotonic or convex regression are useful in many applications. Sometimes the shape assumptions constitute a priori knowledge about the regression function, but often the shape is part of the research question. The authors propose tests for monotonicity and convexity using constrained and unconstrained regression splines. The tests have good large‐sample properties and the small‐sample behaviour is illustrated through simulations. Extensions to the partial linear model and the generalized regression model are presented. The Canadian Journal of Statistics 39: 89–107; 2011 © 2011 Statistical Society of Canada     

A note on testing the regression functions via nonparametric smoothing

The authors present a consistent lack‐of‐fit test in nonlinear regression models. The proposed procedure possesses some nice properties of Zheng's test such as the consistency, the ability to detect any local alternatives approaching the null at rates slower than the parametric rate. What's more, for a predetermined kernel function, the proposed test is more powerful than Zheng's test and the validity of these findings is confirmed by the simulation studies and a real data example. In addition, the authors find out a close connection between the choices of normal kernel functions and the bandwidths. The Canadian Journal of Statistics 39: 108–125; 2011 © 2011 Statistical Society of Canada