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1.
本文检测非参数回归模型均值函数结构变点,针对均值函数跃度的长期均值为零时,基于残量的CUSUM统计量对均值函数结构变点检验无效的问题,本文提出了一种基于均值函数的核估计的检验统计量,得到统计量在原假设和备择假设下的极限分布,并构造Bootstrap方法对非参数回归模型均值函数结构变点进行检验,证明了检验和估计的一致性;模拟结果表明本文方法明显优于已有方法。  相似文献   

2.
基于经验似然对Logistic回归模型进行变点检验及估计.通过建立变点模型,构造经验对数似然比统计量,在大样本下,证明了经验对数似然比统计量与经典参数对数似然比统计量具有相同的极值分布,同时得到变点的估计及估计的相合性,并通过数值模拟及实例说明经验似然方法检验变点的可行性.  相似文献   

3.
随机设计下非参数回归模型方差变点Ratio检验   总被引:1,自引:1,他引:0  
研究随机设计下非参数回归模型方差变点Ratio检验.首先用局部多项式方法估计回归曲线得到残差序列,其次基于残差的平方序列构造Ratio检验统计量并推导检验统计量的极限分布.最后数值模拟与实例分析结果表明方法的有效性.  相似文献   

4.
本文给出了时间序列中方差的小波系数的两种估计:连续估计和离散估计.这两种估计可以用来检测时间序列中方差的结构变点.利用这两种估计我们给出了方差变点的位置和跳跃幅度的估计,并且显示出这些估计可达到最佳收敛速度.同时,我们还给出了这些估计的收敛速度以及检验统计量的渐进分布!  相似文献   

5.
测量误差模型只有一个变点的检验和估计   总被引:5,自引:0,他引:5  
本文讨论了测量误差模型中参数只有一个变点的检验和估计问题,首先,给出其似然比检验统计量,然后,基于最小信息准则的原理,利用Schwarz信息准则(SIC),在多余参数已知和未知的情况下,分别给出了检验统计量,讨论了利用SIC方法给出的检验统计量的渐近分布,证明了基于似然比方法和SIC方法给出的变点估计是相同的,并且在一定条件下,给出了变点估计的极限分布,运用Monte-Carlo随机模拟的方法,分别给出了以上检验的临界值。  相似文献   

6.
刘高生  柏杨  余平 《数学学报》2023,(2):239-252
本文提出了部分函数型线性空间自回归模型的空间效应以及参数效应的假设检验问题.首先利用函数型主成分分析方法估计斜率函数,利用广义矩估计方法估计参数.然后利用得到的相合估计,在原假设和备择假设下,构造了基于残差平方和的检验统计量,同时给出了此检验统计量的渐近性质.模拟结果表明在有限样本下,检验统计量具有良好表现.最后将部分函数型线性空间自回归模型的检验应用到一个关于经济增长的数据案例中,说明所提出的检验统计量的应用表现.  相似文献   

7.
本文考虑变系数ARCH—M模型,构造了非参数部分和参数部分的截面似然估计。基于估计的渐近性质,构造了Wald检验统计量来检验模型是否具有条件异方差性。数值模拟结果表明,所构造的估计和Wald统计量具有良好的有限样本性质。  相似文献   

8.
本文主要研究了非参数回归模型中方差函数的变点, 利用小波方法构造的检验量来检测方差中的变点,建立了这些检验量的渐近分布, 并且运用这些检验量构造了方差变点的位置和跳跃幅度的估计, 给出了这些估计的渐近性质, 并进一步通过随机模拟验证了本文方法在有限样本下的性质.  相似文献   

9.
研究自回归条件异方差(ARCH)模型的多变点检验问题.提出一种拟似然比检验统计量,并在原假设下给出统计量的极限分布.在假设检验过程中得到变点个数的一致估计.数值模拟与实例分析说明了方法的合理性.  相似文献   

10.
当模型误差不是白噪声时,通常的估计方法无效,特别是当回归因子包含后延变量时,估计不相合.因此,文章研究了半参数可加测量误差模型的白噪声检验.提出了一个白噪声检验统计量,并在模型误差是白噪声的零假设下证明了所提检验统计量服从渐近正态分布.随机模拟表明所提出的检验统计量具有良好的检验功效和水平.  相似文献   

11.
《Optimization》2012,61(9):1719-1747
ABSTRACT

By utilizing a min-biaffine scalarization function, we define the multivariate robust second-order stochastic dominance relationship to flexibly compare two random vectors. We discuss the basic properties of the multivariate robust second-order stochastic dominance and relate it to the nonpositiveness of a functional which is continuous and subdifferentiable everywhere. We study a stochastic optimization problem with multivariate robust second-order stochastic dominance constraints and develop the necessary and sufficient conditions of optimality in the convex case. After specifying an ambiguity set based on moments information, we approximate the ambiguity set by a series of sets consisting of discrete distributions. Furthermore, we design a convex approximation to the proposed stochastic optimization problem with multivariate robust second-order stochastic dominance constraints and establish its qualitative stability under Kantorovich metric and pseudo metric, respectively. All these results lay a theoretical foundation for the modelling and solution of complex stochastic decision-making problems with multivariate robust second-order stochastic dominance constraints.  相似文献   

12.
By incorporating both majorization theory and stochastic dominance theory, this paper presents a general theory and a unifying framework for determining the diversification preferences of risk-averse investors and conditions under which they would unanimously judge a particular asset to be superior. In particular, we develop a theory for comparing the preferences of different convex combinations of assets that characterize a portfolio to give higher expected utility by second-order stochastic dominance. Our findings also provide an additional methodology for determining the second-order stochastic dominance efficient set.  相似文献   

13.
Almost stochastic dominance has been receiving more attention in the financial and economic literature. In this short note, we characterize the almost first- and second-degree stochastic dominance by requiring one distribution to be ``close to' a new distribution that dominates or is dominated by another distribution in the traditional sense of the first- and second-order stochastic dominance, respectively. We also investigate the concept of almost stochastic dominance for unbounded random variables.  相似文献   

14.
??Almost stochastic dominance has been receiving more attention in the financial and economic literature. In this short note, we characterize the almost first- and second-degree stochastic dominance by requiring one distribution to be ``close to' a new distribution that dominates or is dominated by another distribution in the traditional sense of the first- and second-order stochastic dominance, respectively. We also investigate the concept of almost stochastic dominance for unbounded random variables.  相似文献   

15.
In this paper we present the problem faced by an electricity retailer which searches to determine its forward contracting portfolio and the selling prices for its potential clients. This problem is formulated as a two-stage stochastic program including second-order stochastic dominance constraints. The stochastic dominance theory is used in order to reduce the risk suffering from low profits. The resulting deterministic equivalent problem is a mixed-integer linear program which is solved using commercial branch-and-cut software. Numerical results for a realistic case study are reported and relevant conclusions are drawn.  相似文献   

16.
This paper analyzes the dual formulation of Post’s [Post, T., 2003. Empirical tests for stochastic dominance efficiency. Journal of Finance 58, 1905–1932] test for second-order stochastic dominance (SSD) efficiency of a given investment portfolio relative to all possible portfolios formed from set of assets. In contrast to the earlier work, we (1) provide a direct proof for the dual that does not rely on expected utility theory, (2) adhere to the original definition of SSD, (3) phrase in terms of a general polyhedral portfolio possibilities set and (4) construct a SSD dominating benchmark portfolio from the optimal solution. To illustrate the dual SSD test, we apply the test to analyze the effect of short-selling restrictions on the profitability of momentum investment strategies.  相似文献   

17.
We consider fixed-size estimation for a linear function of means from independent and normally distributed populations having unknown and respective variances. We construct a fixed-width confidence interval with required accuracy about the magnitude of the length and the confidence coefficient. We propose a two-stage estimation methodology having the asymptotic second-order consistency with the required accuracy. The key is the asymptotic second-order analysis about the risk function. We give a variety of asymptotic characteristics about the estimation methodology, such as asymptotic sample size and asymptotic Fisher-information. With the help of the asymptotic second-order analysis, we also explore a number of generalizations and extensions of the two-stage methodology to such as bounded risk point estimation, multiple comparisons among components between the populations, and power analysis in equivalence tests to plan the appropriate sample size for a study.  相似文献   

18.
We introduce stochastic integer programs with second-order dominance constraints induced by mixed-integer linear recourse. Closedness of the constraint set mapping with respect to perturbations of the underlying probability measure is derived. For discrete probability measures, large-scale, block-structured, mixed- integer linear programming equivalents to the dominance constrained stochastic programs are identified. For these models, a decomposition algorithm is proposed and tested with instances from power optimization.  相似文献   

19.
In this paper we study optimization problems with second-order stochastic dominance constraints. This class of problems allows for the modeling of optimization problems where a risk-averse decision maker wants to ensure that the solution produced by the model dominates certain benchmarks. Here we deal with the case of multi-variate stochastic dominance under general distributions and nonlinear functions. We introduce the concept of ${\mathcal{C}}$ -dominance, which generalizes some notions of multi-variate dominance found in the literature. We apply the Sample Average Approximation (SAA) method to this problem, which results in a semi-infinite program, and study asymptotic convergence of optimal values and optimal solutions, as well as the rate of convergence of the feasibility set of the resulting semi-infinite program as the sample size goes to infinity. We develop a finitely convergent method to find an ${\epsilon}$ -optimal solution of the SAA problem. An important aspect of our contribution is the construction of practical statistical lower and upper bounds for the true optimal objective value. We also show that the bounds are asymptotically tight as the sample size goes to infinity.  相似文献   

20.
文平  黄薏舟 《运筹与管理》2017,26(10):153-156
本文依据参照依赖偏好模型提出了基于随机参照点的风险度量方法,进而构建了均值-风险模型,并讨论了该决策方法与随机占优之间的一致性。研究发现,该决策方法不仅与一级随机占优是一致的而且与二级随机占优也是一致的。由于二级随机占优与期望效用理论的一致性,因而所构建的均值-风险模型与期望效用理论也是一致的。  相似文献   

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