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   6706篇
  免费   263篇
  国内免费   96篇
管理学   513篇
民族学   32篇
人口学   170篇
丛书文集   554篇
理论方法论   199篇
综合类   4400篇
社会学   230篇
统计学   967篇
  2024年   25篇
  2023年   60篇
  2022年   77篇
  2021年   98篇
  2020年   111篇
  2019年   131篇
  2018年   149篇
  2017年   160篇
  2016年   208篇
  2015年   206篇
  2014年   394篇
  2013年   696篇
  2012年   458篇
  2011年   464篇
  2010年   379篇
  2009年   346篇
  2008年   374篇
  2007年   433篇
  2006年   411篇
  2005年   355篇
  2004年   351篇
  2003年   307篇
  2002年   261篇
  2001年   202篇
  2000年   126篇
  1999年   56篇
  1998年   26篇
  1997年   14篇
  1996年   20篇
  1995年   27篇
  1994年   23篇
  1993年   16篇
  1992年   12篇
  1991年   13篇
  1990年   16篇
  1989年   14篇
  1988年   11篇
  1987年   4篇
  1986年   2篇
  1985年   4篇
  1984年   11篇
  1983年   3篇
  1982年   2篇
  1981年   2篇
  1980年   2篇
  1978年   1篇
  1977年   4篇
排序方式: 共有7065条查询结果,搜索用时 15 毫秒
101.
This paper is dedicated to the study of the composite quantile regression (CQR) estimations of time-varying parameter vectors for multidimensional diffusion models. Based on the local linear fitting for parameter vectors, we propose the local linear CQR estimations of the drift parameter vectors, and verify their asymptotic biases, asymptotic variances and asymptotic normality. Moreover, we discuss the asymptotic relative efficiency (ARE) of the local linear CQR estimations with respect to the local linear least-squares estimations. We obtain that the local estimations that we proposed are much more efficient than the local linear least-squares estimations. Simulation studies are constructed to show the performance of the estimations proposed.  相似文献   
102.
西安事变的和平解决成为国共两党由内战到合作杭日时局转换的枢纽,促成西安事变和平解决的主要因素有:一、中国共产党以民族大计为重,从中协调。二、蒋介石被迫反省,改弦更张。三、张学良、杨虎城两位将军无私无畏,肝胆相照。四、宋氏兄妹从中斡旋,入情入理。西安事变得以和平解决是诸多因素促成的结果,缺少任何一个方面,西安事变的和平解决都是不可能的。  相似文献   
103.
This paper considers the problem where the linear discriminant rule is formed from training data that are only partially classified with respect to the two groups of origin. A further complication is that the data of unknown origin do not constitute an observed random sample from a mixture of the two under- lying groups. Under the assumption of a homoscedastic normal model, the overall error rate of the sample linear discriminant rule formed by maximum likelihood from the partially classified training data is derived up to and including terms of the first order in the case of univariate feature data. This first- order expansion of the sample rule so formed is used to define its asymptotic efficiency relative to the rule formed from a completely classified random training set and also to the rule formed from a completely unclassified random set.  相似文献   
104.
袁野 《学术探索》2012,(1):70-73
要提升我国软件产业的竞争力,研究其影响因素是非常重要的课题。本文首先对产业竞争力的概念、产业竞争力影响模型以及软件产业竞争力的研究进行简要回顾,然后详细探讨了软件产业竞争的特点,在此基础上构建了我国软件产业国际竞争力影响因素模型,接着对模型中的各个要素,如政府的作用、人力资源、产业组织、产业价值链、企业管理等进行了深入的分析,最后对各个要素的相互关系进行了初步论述。  相似文献   
105.
An introduction is provided to this Social Development Quartet in which the articles focus on parent emotion socialization in the context of psychopathology and risk. In two articles, the samples of children and/or adolescents have a psychiatric diagnosis [oppositional defiant disorder (ODD) or depressive disorder]. The other two articles feature samples in which children and families have experienced serious risks [exposure to inter‐parental violence (IPV) or maternal incarceration]. The articles in this Social Development Quartet extend our knowledge of the impact of parental emotion socialization practices to contexts in which children and parents experience higher than normative risks. The work reported in these articles builds upon research on emotion socialization in normative contexts, illustrating the buffering effects of supportive parenting as well as its limits.  相似文献   
106.
Data envelopment analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency [B. Hollingsworth, The measurement of efficiency and productivity of health care delivery. Health Economics 17(10) (2008), pp. 1107–1128], but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized [B.J. Gajewski, R. Lee, M. Bott, U. Piamjariyakul, and R.L. Taunton, On estimating the distribution of data envelopment analysis efficiency scores: an application to nursing homes’ care planning process. Journal of Applied Statistics 36(9) (2009), pp. 933–944; J. Ruggiero, Data envelopment analysis with stochastic data. Journal of the Operational Research Society 55 (2004), pp. 1008–1012]. We propose to address measurement error systematically using a Bayesian method (Bayesian DEA). We will apply Bayesian DEA to data from the National Database of Nursing Quality Indicators® to estimate nursing units’ efficiency. Several external reliability studies inform the posterior distribution of the measurement error on the DEA variables. We will discuss the case of generalizing the approach to situations where an external reliability study is not feasible.  相似文献   
107.
现阶段,随着图书馆馆藏图书的增多,使中文编目数据的工作量逐渐增大,为了进一步提高工作效率和质量,有必要对中文编目数据过程中难以控制的因素进行分析,并采取相应的手段加以控制,就中文编目数据工作过程中难以控制的因素展开探讨。  相似文献   
108.
《Statistics》2012,46(6):1396-1436
ABSTRACT

The paper deals with an asymptotic relative efficiency concept for confidence regions of multidimensional parameters that is based on the expected volumes of the confidence regions. Under standard conditions the asymptotic relative efficiencies of confidence regions are seen to be certain powers of the ratio of the limits of the expected volumes. These limits are explicitly derived for confidence regions associated with certain plugin estimators, likelihood ratio tests and Wald tests. Under regularity conditions, the asymptotic relative efficiency of each of these procedures with respect to each one of its competitors is equal to 1. The results are applied to multivariate normal distributions and multinomial distributions in a fairly general setting.  相似文献   
109.
The hazard rate (HR) and mean residual lifetime are two of the most practical and best-known functions in biometry, reliability, statistics and life testing. Recently, the reversed HR function is found to have interesting properties useful in additional areas such as censored data and forensic science. For these three biometric functions, we propose testing methods that they take on a known functional form against that they dominate or are dominated by this known form. This goodness-of-fit-type testing is wider in applications and more interesting than the long-standing testing procedures for exponentiality against the monotonicity of these functions or even the change point problems. This is so since we can test against any choice of the survival distribution and not just exponentiality. For this general testing, we present easy to implement tests and generalize them into classes of statistics that could lead to more powerful and efficient testing.  相似文献   
110.
构建澜湄国家命运共同体是中国周边外交和亚洲命运共同体构想的具体实践,将助力东盟共同体建设,促进次区域稳定和繁荣。本文通过对澜湄命运共同体建设的意义、动因和影响因素分析,提出了澜湄命运共同体建设的路径选择。  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