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121.
论证企业间以排放指标为标的的排污交易、环境主管部门与企业间的排污行政许可及排污费是相互独立的法律关系,三者具有不同的法律性质,提出对它们分别进行法律规制的设想。认为为使环境行政管理不对排污指标的市场配置机制造成障碍,法律应明确排污交易适用商事交易规则,对于排污交易引起的排污权主体变动,应以对出卖排污指标企业进行许可证变更或解除以及由购进排污指标企业申请新排污许可的制度模式进行承认。此外,还论述环境管理部门在排污交易相关管理体系中应具有的法律功能。  相似文献   
122.
"十一五"时期减排取得的成效和经验为完成"十二五"更加严格、全面的减排任务打下了良好的基础,但"十二五"时期我国污染减排也面临存量减排空间缩小、后续减排难度增大、新增减排领域能力建设滞后、企业减排信心不足、污染治理成本上升等一系列问题和困难。为此,应着力推进减排技术与制度创新,进一步加强工程减排、结构减排和管理减排,以确保"十二五"减排目标顺利实现,全面改善环境质量。  相似文献   
123.
The author introduces new statistics suited for testing uniformity of circular distributions and powerful against multimodal alternatives. One of them has a simple expression in terms of the geometric mean of the sample of chord lengths. The others belong to a family indexed by a continuous parameter. The asymptotic distributions under the null hypothesis are derived. We compare the power of the new tests against Stephens's alternatives with those of Ajne, Watson, and Hermans‐Rasson's tests. Some of the new tests are the most powerful when the alternative has three or four modes. A heuristic justification of this feature is given. An application to the analysis of archaeological data is provided. The Canadian Journal of Statistics 38:80–96; 2010 © 2010 Statistical Society of Canada  相似文献   
124.
Testing for stochastic order among K populations is a common and important problem in statistical practice. It arises in the analysis of both planned experiments and observational studies. The authors develop a new nonparametric test for order among K populations that can accommodate any stochastic ordering. The test is based on a maximally selected chi‐bar‐square statistic. The authors find its limiting distribution and use simulations to derive critical values. Three important examples are used to illustrate the applicability of the general method. The authors find that the new tests outperform the existing methods in many practical cases. The Canadian Journal of Statistics 38: 97–115; 2010 © 2009 Statistical Society of Canada  相似文献   
125.
Variability explained by covariates or explained variance is a well‐known concept in assessing the importance of covariates for dependent outcomes. In this paper we study R2 statistics of explained variance pertinent to longitudinal data under linear mixed‐effect models, where the R2 statistics are computed at two different levels to measure, respectively, within‐ and between‐subject variabilities explained by the covariates. By deriving the limits of R2 statistics, we find that the interpretation of explained variance for the existing R2 statistics is clear only in the case where the covariance matrix of the outcome vector is compound symmetric. Two new R2 statistics are proposed to address the effect of time‐dependent covariate means. In the general case where the outcome covariance matrix is not compound symmetric, we introduce the concept of compound symmetry projection and use it to define level‐one and level‐two R2 statistics. Numerical results are provided to support the theoretical findings and demonstrate the performance of the R2 statistics. The Canadian Journal of Statistics 38: 352–368; 2010 © 2010 Statistical Society of Canada  相似文献   
126.
127.
Quantile-based reliability analysis has received much attention recently. We propose new quantile-based tests for exponentiality against decreasing mean residual quantile function (DMRQ) and new better than used in expectation (NBUE) classes of alternatives. The exact null distribution of the test statistic is derived when the alternative class is DMRQ. The asymptotic properties of both the test statistics are studied. The performance of the proposed tests with other existing tests in the literature is evaluated through simulation study. Finally, we illustrate our test procedure using real data sets.  相似文献   
128.
We develop a stochastic model describing the joint distribution of (X,N), where N has a geometric distribution while X is the sum of N dependent, heavy-tail Pareto components. Models of this form arise in many applications, ranging from hydro-climatology to finance and insurance. We present fundamental properties of this vector, including marginal and conditional distributions, moments, representations, and parameter estimation. We also include an example from finance, illustrating modeling potential of this new bivariate distribution.  相似文献   
129.
We consider the optimal consumption and portfolio selection problem with constant absolute risk aversion (CARA) utility. The economic agent in this model receives constant labor income, and her economic behavior is restricted on consumption and wealth, which are called the subsistence consumption constraint and the negative wealth constraint. We use the convex duality method to derive the value function and the optimal policies in closed-form solutions. Also we illustrate some numerical examples.  相似文献   
130.
In this paper, the limit distribution of the least squares estimator for mildly explosive autoregressive models with strong mixing innovations is established, which is shown to be Cauchy as in the iid case. The result is applied to identify the onset and the end of an explosive period of an econometric time series. Simulations and data analysis are also conducted to demonstrate the usefulness of the result.  相似文献   
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