首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1456篇
  免费   42篇
  国内免费   12篇
管理学   103篇
民族学   4篇
人口学   29篇
丛书文集   45篇
理论方法论   27篇
综合类   492篇
社会学   18篇
统计学   792篇
  2024年   1篇
  2023年   9篇
  2022年   23篇
  2021年   12篇
  2020年   38篇
  2019年   56篇
  2018年   62篇
  2017年   78篇
  2016年   51篇
  2015年   52篇
  2014年   89篇
  2013年   219篇
  2012年   127篇
  2011年   75篇
  2010年   61篇
  2009年   58篇
  2008年   59篇
  2007年   78篇
  2006年   55篇
  2005年   35篇
  2004年   49篇
  2003年   39篇
  2002年   28篇
  2001年   29篇
  2000年   21篇
  1999年   23篇
  1998年   16篇
  1997年   11篇
  1996年   11篇
  1995年   8篇
  1994年   5篇
  1993年   5篇
  1992年   9篇
  1991年   4篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1986年   1篇
  1985年   2篇
  1984年   1篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
排序方式: 共有1510条查询结果,搜索用时 15 毫秒
1.
2.
Abstract

The mean estimators with ratio depend on multiple auxiliary variables and unknown parameters in a finite population setting. We propose a new generalized approach with matrices for modeling the mutivariate mean estimators with two auxiliary variables. Our approach brings naturally a graphical analysis for comparing mean estimators.  相似文献   
3.
Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.  相似文献   
4.
提出了变质量系统的相对论性万有D’Alembert原理,构造了相对论性广义动能函数,建立了变质量任意阶非线性非完整系统在准坐标下和广义坐标下的相对论性广义Mar-Millan型方程,并得到厂相应的型方程  相似文献   
5.
The labor quality index (LQI) not only serves as an important reference for monitoring the progress of the sustainable development of a country, but it can also serve as an important parameter for economic analysis. To compile such an index for Taiwan, we conducted two large-scale surveys of 1000 major enterprises and 844 union leaders, respectively, to determine the appropriate weights for each key factor. We also searched for all the relevant statistics that were used to calculate the weighted sum of the 25 sub-indexes, in order to compile a LQI for Taiwan’s manufacturing industries covering the period from 1990-2000. Our calculations show that this LQI rose from 80.2 in 1990 to 117.5 in 2000, which reflected an impressive 37.3% increase in just one decade. This rate of growth has, however, been slowing down since 1997. Our results indicate that the LQI provides a valuable indicator for monitoring the enhancement of labor quality in this society.  相似文献   
6.
WEIGHTED SUMS OF NEGATIVELY ASSOCIATED RANDOM VARIABLES   总被引:2,自引:0,他引:2  
In this paper, we establish strong laws for weighted sums of negatively associated (NA) random variables which have a higher‐order moment condition. Some results of Bai Z.D. & Cheng P.E. (2000) [Marcinkiewicz strong laws for linear statistics. Statist. and Probab. Lett. 43, 105–112,] and Sung S.K. (2001) [Strong laws for weighted sums of i.i.d. random variables, Statist. and Probab. Lett. 52, 413–419] are sharpened and extended from the independent identically distributed case to the NA setting. Also, one of the results of Li D.L. et al. (1995) [Complete convergence and almost sure convergence of weighted sums of random variables. J. Theoret. Probab. 8, 49–76,] is complemented and extended.  相似文献   
7.
IntroductionCulturegivesanindividualananchoringpoint,ani dentity ,aswellascodesofconduct (MichaelR ,Iikka ,andMichaelH 2 0 0 2 :33) .Ofmorethan 16 0definitionsofculture (AlfredandClyde 1985 :11) ,mostagreeonsomebasicprinciples ,butthereisalotofvariationonthedetails .Cultureisalsomultidimensional ,consistingofanumberofcommonelementsthatareinterdependent.Thedifferencesinculturehaveanimportantimpactonmanyaspectsofamultinationalcompany’sactivity .Thispaperwillmainlydiscusstheeffectofsomeofthe…  相似文献   
8.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
9.
教育服务是服务核算中的一个重要部分。本文讨论教育服务的定义和服务产出的数量单位。研究教育服务的核算范围和计算教育服务产出价值的方法,以及教育服务的质量调整问题。最后,举例使用产出指标方法计算教育产出。  相似文献   
10.
A common problem in environmental epidemiology is the estimation and mapping of spatial variation in disease risk. In this paper we analyse data from the Walsall District Health Authority, UK, concerning the spatial distributions of cancer cases compared with controls sampled from the population register. We formulate the risk estimation problem as a nonparametric binary regression problem and consider two different methods of estimation. The first uses a standard kernel method with a cross-validation criterion for choosing the associated bandwidth parameter. The second uses the framework of the generalized additive model (GAM) which has the advantage that it can allow for additional explanatory variables, but is computationally more demanding. For the Walsall data, we obtain similar results using either the kernel method with controls stratified by age and sex to match the age–sex distribution of the cases or the GAM method with random controls but incorporating age and sex as additional explanatory variables. For cancers of the lung or stomach, the analysis shows highly statistically significant spatial variation in risk. For the less common cancers of the pancreas, the spatial variation in risk is not statistically significant.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号