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1.
任瑞林  马湘玲 《河南科学》1992,10(3):221-230
在有限总体的抽样调查理论中,辅助信息的应用和轮换样本方法在经常性调查中占有重要的地位.本文将辅助信息的应用和轮换样本方法推广到了时变总体情形.对一个时变总体进行经常性调查时,利用前次查的结果,可以提高本次调查结果的精度,节省调查的费用.本文的结果可以直接应用于大规模的人口抽样调查,社会经济抽样调查等。  相似文献   

2.
针对实际连续抽样调查中样本轮换的广泛应用,将简单随机抽样场合下的样本轮换问题推广到分层简单随机连续抽样、整群连续抽样,并讨论其估计量、样本量、最优权数以及最优样本轮换率.  相似文献   

3.
部分估计中样本容量确定问题一直是抽样调查学科中社会需求性很强的一个重要课题.就部分估计中以总量的有效精度控制下代表总体的样本容量估计问题,以一般常用的估计方法为切入点,分析了其优缺点,在此基础上,采用类二次抽样引入修正方差法来确定样本容量.  相似文献   

4.
为了精确估计正值alpha稳定(PAS)分布的参数,基于负数阶矩理论,提出了比值估计、对数矩估计和迭代对数矩估计3种参数估计方法.比值估计直接利用特定阶次的负数阶矩的比值来估计未知参数,对数矩估计利用PAS分布的对数变换及其负数阶矩的Taylor展式从而获得解析的估计形式,迭代对数矩估计通过样本分段迭代估计未知参数.与传统的估计方法相比,所提出的3种估计方法可以获得更高的估计精度,并且对数矩估计具有较低的计算复杂度.MonteCarlo仿真实验表明,当独立运行次数为100、样本总数为5000时,比值估计的估计精度可以达到99.8%,对数矩估计的估计精度可以达到99.95%,迭代对数矩估计的估计精度可以达到99.94%.  相似文献   

5.
本文研究整群抽样调查中在不满足分群原则时,可利用回归估计提高估计精度的方法,并通过实例说明,回归估计法应用于整群抽样是降低抽样误差的有效方法。  相似文献   

6.
在众多社会经济调查中,由于种种原因不能对总体进行全面调查。因此历史信息的利用起着重要作用。本文主要讨论在有限总体的相继抽样调查中如何利用历史资料It,得到时间序列θt的一个较为理想的估计。以利用历史资料提高本次抽样调查结果精度、节省调查费用。  相似文献   

7.
讨论了等距抽样中,如何利用辅助信息改进总体平均值的估计,以达到提高估计精度之目的。分单组样本和抽取附加样本两种情况,提出了总体平均值的回归型估计。文中提出的估计与传统的样本均值相比较有较高的精度。  相似文献   

8.
讨论了等距抽样中,如何利用辅助信息改进总体平均值的估计,以达到提高估计精度之目的.分单组样本和抽取附加样本两种情况,提出了总体平均值的回归型估计.文中提出的估计与传统的样本均值相比较有较高的精度.  相似文献   

9.
研究了排序集抽样下样本参数的修正极大似然估计的性质,并以此估计为基础构造了样本参数的修正区间估计.研究表明:在相同的置信水平下,基于排序集抽样的样本参数的修正区间估计较传统的置信区间具有更高的精度.  相似文献   

10.
通过对我国工业统计抽样调查实际工作中的有关方法制度的分析研究,阐明了关于我国省级工业抽样调查中的样本框的构造和分解方法;对于各分解后的样本进行特征值分析和相关分析,提出了多目标(指标)抽样调查的样本数目确定的综合排序分析方法。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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