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   659篇
  免费   32篇
  国内免费   6篇
管理学   83篇
民族学   3篇
人口学   6篇
丛书文集   23篇
理论方法论   6篇
综合类   315篇
社会学   1篇
统计学   260篇
  2023年   6篇
  2022年   8篇
  2021年   8篇
  2020年   16篇
  2019年   20篇
  2018年   24篇
  2017年   44篇
  2016年   27篇
  2015年   26篇
  2014年   36篇
  2013年   106篇
  2012年   54篇
  2011年   43篇
  2010年   35篇
  2009年   26篇
  2008年   32篇
  2007年   41篇
  2006年   30篇
  2005年   18篇
  2004年   20篇
  2003年   13篇
  2002年   6篇
  2001年   6篇
  2000年   10篇
  1999年   3篇
  1998年   4篇
  1997年   7篇
  1996年   5篇
  1995年   6篇
  1994年   3篇
  1993年   5篇
  1992年   2篇
  1991年   3篇
  1988年   2篇
  1985年   1篇
  1982年   1篇
排序方式: 共有697条查询结果,搜索用时 890 毫秒
81.
Expressions for the entropy, the Kullback-Leibler information, and the I α-information are established for distributions of progressively Type-II censored order statistics. These results are used to identify minimum and maximum information censoring plans. In particular, we find minimum and maximum entropy plans for DFR, exponential, Pareto, reflected power, and Weibull distributions. The results for Kullback-Leibler and I α-information hold for any continuous distribution.  相似文献   
82.
ABSTRACT

We propose two non parametric portmanteau test statistics for serial dependence in high dimensions using the correlation integral. One test depends on a cutoff threshold value, while the other test is freed of this dependence. Although these tests may each be viewed as variants of the classical Brock, Dechert, and Scheinkman (BDS) test statistic, they avoid some of the major weaknesses of this test. We establish consistency and asymptotic normality of both portmanteau tests. Using Monte Carlo simulations, we investigate the small sample properties of the tests for a variety of data generating processes with normally and uniformly distributed innovations. We show that asymptotic theory provides accurate inference in finite samples and for relatively high dimensions. This is followed by a power comparison with the BDS test, and with several rank-based extensions of the BDS tests that have recently been proposed in the literature. Two real data examples are provided to illustrate the use of the test procedure.  相似文献   
83.
Abstract

The most commonly studied generalized normal distribution is the well-known skew-normal by Azzalini. In this paper, a new generalized normal distribution is defined and studied. The distribution is unimodal and it can be skewed right or left. The relationships between the parameters and the mean, variance, skewness, and kurtosis are discussed. It is observed that the new distribution has a much wider range of skewness and kurtosis than the skew-normal distribution. The method of maximum likelihood is proposed to estimate the distribution parameters. Two real data sets are applied to illustrate the flexibility of the distribution.  相似文献   
84.
Vasicek [1] Vasicek, O. 1976. A test for normality based on sample entropy. J. R. Statist. Soc. B, 38: 5459.  [Google Scholar]used the “convolution of twelve uniforms” for a Monte Carlo tabulation of the 5% critical values for his entropy test for normality. We employ a superior normal generator to construct a corrected and extended tabulation for his test. Interestingly, it is shown that, the same tables can be used for implementing Mudholkar and Tian's [2] Mudholkar, G. S. and Tian, L. 1999. “An entropy characterization of the inverse Gaussian distribution and related goodness-of-fit test”. In Tech. Rep., University of Rochester Rochester, NY Submitted for publication [Google Scholar]entropy test for the composite inverse Gaussian hypothesis. The finding extends the known Gaussian, inverse Gaussian analogies.  相似文献   
85.
This article develops nonparametric tests of independence between two stochastic processes satisfying β-mixing conditions. The testing strategy boils down to gauging the closeness between the joint and the product of the marginal stationary densities. For that purpose, we take advantage of a generalized entropic measure so as to build a whole family of nonparametric tests of independence. We derive asymptotic normality and local power using the functional delta method for kernels. As a corollary, we also develop a class of entropy-based tests for serial independence. The latter are nuisance parameter free, and hence also qualify for dynamic misspecification analyses. We then investigate the finite-sample properties of our serial independence tests through Monte Carlo simulations. They perform quite well, entailing more power against some nonlinear AR alternatives than two popular nonparametric serial-independence tests.  相似文献   
86.
In this article, a new method to estimate the Jackknifed generalized ridge tuning parameter, based on the Jackknifed Ridge-trace and an analytical method borrowed from generalized maximum entropy, is presented. The ideas in the article are illustrated and evaluated using to the well-known Portland cement data set and simulations.  相似文献   
87.
Abstract

In time series, it is essential to check the independence of data by means of a proper method or an appropriate statistical test before any further analysis. Therefore, among different independence tests, a powerful and productive test has been introduced by Matilla-García and Marín via m-dimensional vectorial process, in which the value of the process at time t includes m-histories of the primary process. However, this method causes a dependency for the vectors even when the independence assumption of random variables is considered. Considering this dependency, a modified test is obtained in this article through presenting a new asymptotic distribution based on weighted chi-square random variables. Also, some other alterations to the test have been made via bootstrap method and by controlling the overlap. Compared with the primary test, it is obtained that not only the modified test is more accurate but also, it possesses higher power.  相似文献   
88.
This paper introduces a general goodness-of-fit test based on the estimated Kullback–Leibler information. The test uses the Vasicek entropy estimate. Two special cases of the test for location–scale and shape families are discussed. The results are used to introduce goodness-of-fit tests for the uniform, Laplace, Weibull and beta distributions. The critical values and powers for some alternatives are obtained by simulation.  相似文献   
89.
提升产业链供应链现代化水平是推动经济体系优化升级的重点任务。论文首先界定了产业链供应链现代化的内涵,并根据其内涵构建综合评价指标体系。然后,研究2011—2020年产业链供应链现代化水平的分布动态、区域差异与空间收敛性。结果表明:我国产业链供应链现代化水平在空间上呈现出“东高、中西低”的阶梯状空间分布特征;区域产业链供应链现代化水平差异主要来源于区域间差异,而区域间差异主要来源于东部-中部和东部-西部的地区差异;全国及各区域产业链供应链现代化水平在空间上无明显σ收敛特征,全国及各区域存在显著的绝对β收敛和条件β收敛,表明各区域朝着自身稳定状态发展。最后根据研究结果,提出关于产业链供应链现代化水平提升的对策建议。  相似文献   
90.
For the analysis of square contingency tables with ordered categories, Goodman considered the diagonals-parameter symmetry (DPS) model. This paper proposes a measure to represent the degree of departure from the DPS model. The proposed measure is expressed by applying Read and Cressie’s power-divergence or Patil and Taillie’s diversity index. The measure would be useful for comparing the degree of departure from the DPS model in several tables. Examples are given.  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