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On hypothesis testing with a partitioned random alternative

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Science China Mathematics 2010年第4期53卷 927-938页

作者： WANG WeiZhen department of Mathematics and statistics,Wright state university,Dayton,OH 45435,usa 1. department of Mathematics and statistics Wright State University Dayton OH 45435 USA

It is common in statistical practice that one needs to make a choice among m + 1 mutually exclusive claims on *** m=1,it is done by the (traditional) hypothesis *** this paper,a generalization to the case m > 1 is *** fundamental difference with the case m=1 is that the new alternative hypothesis is a partition of m multiple claims and is *** is used to decide which claim in the partition is to be tested as the ***,a random alternative is *** conditional and overall type I errors of the proposed test are controlled at a given level,and this test can be used as a new solution for the general multiple test *** classical problems,including the one-sample problem,model selection in multiple linear regression,and multi-factor analysis,are revisited,and new tests are provided ***,the famous two-sided t-test should be replaced by the proposed.

关键词： analysis of variance conditional probability multiple linear regression one-sample problem

On a robust and effcient maximum depth estimator

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Science China Mathematics 2009年第6期52卷 1212-1232页

作者： ZUO YiJun1,2 & LAI ShaoYong1 1 School of Economic Mathematics,Southwestern university of Finance and Economics,Chengdu 610074,China 2 department of statistics and probability,michigan state university,east lansing,mi 48823,usa

The best breakdown point robustness is one of the most outstanding features of the univariate *** this robustness property,the median,however,has to pay the price of a low effciency at normal and other light-tailed *** equivariant multivariate analogues of the univariate median with high breakdown points were constructed in the past two *** the high breakdown robustness,most of them also have to sacrifice their effciency at normal and other models,*** affine equivariant maximum depth estimator proposed and studied in this paper turns out to be an *** the univariate median,it also possesses a highest breakdown point among all its multivariate *** the univariate median,it is also highly efficient relative to the sample mean at normal and various other distributions,overcoming the vital low-effciency shortcoming of the univariate and other multivariate generalized *** paper also studies the asymptotics of the estimator and establishes its limit distribution without symmetry and other strong assumptions that are typically imposed on the underlying distribution.

关键词： data depth maximum depth estimator median location estimator breakdown point asymptotic distribution robustness effciency

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相关数据密度函数的非线性小波估计

系统科学与数学 2002年第4期22卷 497-506页

作者：张双林郑忠国 department 北京大学概率统计系北京100871

本文考虑了严平稳随机序列密度函数的非线性小波估计,证明了在Besov空间中,非线性小波估计可达到最优收敛速度.进一步讨论了自适应非线性小波估计,证明了自适非线性小波估计可达到次最优速度即和最优速度相差in n.

关键词：相关数据密度函数非线性小波估计概率密度估计

Optimal MAC based cooperative spectrum sensing in cognitive radio networks

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Science China(Information Sciences) 2012年第6期55卷 1388-1396页

作者： CHEN Zhong 1,ZHANG XianDa 1 & YANG LanJuan 2 1 state Key Laboratory of Intelligent Technology and Systems,Tsinghua National Laboratory for Information Science and Technology,department of Automation,Tsinghua university,Beijing 100084,China 2 Institute of Command Automation,PLA university of Science and Technology,Nanjing 210007,China 1. state Key Laboratory of Intelligent Technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Automation Tsinghua University Beijing 100084 China2. Institute of Command Automation PLA University of Science and Technology Nanjing 210007 China

This paper considers a cognitive radio (CR) system in non-ideal fading wireless channels and pro-poses cooperative spectrum sensing schemes based on coherent multiple access channels (MAC),serving as an alternative way to improve the cooperative spectrum sensing performance and provide space diversity for spec-trum *** statistics are transmitted using a common channel from the secondary users (SUs) to a fusion center (FC) where the global decision is *** optimal scaling factors of the proposed schemes are obtained by maximizing the detection probability under a target false alarm probability and a transmit power *** the proposed optimal MAC scheme has high computational complexity,a sub-optimal solu-tion based on maximization of the deflection coefficient (DC) is also *** results show that the proposed algorithms can significantly improve the spectrum sensing performance and approach the detection baseline.

关键词： cognitive radio (CR) spectrum sensing multiple access channel (MAC) deflection coefficient optimization

HEAVY TRAFFIC LImiT THEOREMS IN FLUID BUFFER MODELS

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Journal of Systems Science & Complexity 2004年第1期17卷 1-15页

作者： YINGang ZHANGHanqin departmentofMathematics WayneStateUniversityDetroitMI48202USA) InstituteofAppliedMathematics AcademyofMathematicsandSystemsSciencesChineseAcademyofSciencesBeijing100080China

A fluid buffer model with Markov modulated input-output rates is *** traffic intensity is near its critical value, the system is known as in heavy *** is shown that a suitably scaled sequence of the equilibrium buffer contents has a weakor distributional limit under heavy traffic conditions. This weak limit is a functional of adiffusion process determined by the Markov chain modulating the input and output *** first passage time of the reflected process is examined. It is shown that the mean firstpassage time can be obtained via a solution of a Dirichlet problem. Then the transitiondensity of the reflected process is derived by solving the Kolmogorov forward equation witha Neumann boundary condition. Furthermore, when the fast changing part of the generatorof the Markov chain is a constant matrix, the representation of the probability distributionof the reflected process is derived. Upper and lower bounds of the probability distributionare also obtained by means of asymptotic expansions of standard normal distribution.

关键词： fluid model markov chain singular perturbation diffusion process

A New Approach to Exponential Stabilization for A Class of Nonlinear Networked Systems with Stochastic Delays

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A New Approach to Exponential Stabilization for A Class of N...

Estimation of Spectral Gap for Markov Chains

第24届中国控制与决策会议

作者： Hejun Yao 1 , Zheng Yuan 2 1. School of Mathematics and statistics, Anyang Normal university, Anyang 455002, China2. department of Mathematics, Zhengzhou university, Zhengzhou 455000, China

A new approach to exponential stabilization for a class of nonlinear networked systems with stochastic delays is given in this paper. By using the fuzzy T-S method, a new model of nonlinear networked control systems with is derived. The networked induced delays are assumed to have some stochastic characteristics. A stochastic variable satisfying Bernoulli distribution is introduced with the probability of the delays taking value in different interval. With the Lyapunov stability theorem, a exponential stabilization condition and a state feedback controller design method are obtained. And all the conditions are expressed in terms of Lmi. Finally, a numerical example is given to demonstrate the validity of the results.

关键词： Networked control systems Exponential Stability Stochastic delay

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Acta Mathematica Sinica,English Series 1996年第4期12卷 337-360页

作者： Chen Mufa department of Mathematics Beijing Normal university Beijing, 100875 China department of Mathematics Beijing Normal University Beijing China

The study of the convergent rate (spectra gap) in the L^2-sense is motivated from several different fields: probability statistics, mathematical physics, computer science and so on and it is now an artive research topic. Based on a new approach (the coupling technique) introduced in [7] for the estimate of the convergent rate and as a continuation of [4],[5],[7-9],[23] and [24], this paper studies the estimate of the rate for time-continuous Markov chains. Two variational formulas for the rate are presented here for the first time for birth-death processes. For diffusions, similar results are presented in an accompany paper [10]. The new formulas enable us to recover or improve the main known results. The connection between the sharp estimate and the corresponding eigenfunction is explored and illustrated by various examples. A previous result on optimal Markovian couplings is also extended in the paper.

关键词： Markov chains Spectral gap Couplings

非人类免疫缺陷病毒感染的早期梅毒患者出现血清固定概率的列线图预测模型

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传染病信息 2024年第3期37卷 208-214页

作者：李蜜蒋进溧阳市人民医院皮肤科 213300

目的建立并验证包含3个临床参数的列线图预测模型,预测人类免疫缺陷病毒阴性早期梅毒患者治疗后出现血清固定的发生概率。方法检索溧阳市人民医院的门诊数据,将2017年9月1日至2019年9月30日诊治的431例早期梅毒患者纳入建模队列建立预... 详细信息

目的建立并验证包含3个临床参数的列线图预测模型,预测人类免疫缺陷病毒阴性早期梅毒患者治疗后出现血清固定的发生概率。方法检索溧阳市人民医院的门诊数据,将2017年9月1日至2019年9月30日诊治的431例早期梅毒患者纳入建模队列建立预测模型,将2019年11月1日至2022年12月30日诊治的172例早期梅毒患者纳入验证队列。采用单因素和多因素Logistic回归分析筛选出现血清固定状态的独立危险因素。根据回归系数绘制相应的列线图预测模型;采用曲线下面积值评价其区分度;通过校准曲线评估校准度;采用决策曲线分析评价净效益。结果多因素Logistic回归分析结果显示,年龄、初始快速血浆反应试验滴度和性生活时间点3个因素是患者出现血清固定状态的独立危险因素。列线图预测模型的曲线下面积在建模和验证队列中分别为0.816和0.726,显示出良好的性能。预测模型校准良好,决策曲线分析显示,当出现血清固定的阈值概率在75%~95%时,使用该模型预测出现血清固定的概率将获得净收益。结论该列线图预测模型可为非HIV感染的早期梅毒患者出现血清固定概率提供个体化预测。

关键词：早期梅毒血清固定列线图回顾性研究

国有大中型亏损企业三年脱困的标准和可行性分析

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统计研究 1999年第8期16卷 25-28页

作者： Research Team Under the department of Industry and Communication statistics(25) 国家统计局·工业交通统计司

党中央、国务院于１９９７年提出用三年左右的时间使大多数国有大中型亏损企业摆脱困境的目标。１９９８年是扭亏解困的第一年，从实际情况看，形势并不乐观，亏损面由１９９７年的３９．１％上升到１９９８年的４３％（快报数）。九届... 详细信息

党中央、国务院于１９９７年提出用三年左右的时间使大多数国有大中型亏损企业摆脱困境的目标。１９９８年是扭亏解困的第一年，从实际情况看，形势并不乐观，亏损面由１９９７年的３９．１％上升到１９９８年的４３％（快报数）。九届人大二次会议的政府工作报告中重申了...

关键词：国有企业大中型企业扭亏脱困可行性分析