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   10876篇
  免费   24篇
管理学   1553篇
民族学   103篇
人才学   1篇
人口学   2441篇
丛书文集   2篇
理论方法论   545篇
综合类   288篇
社会学   4730篇
统计学   1237篇
  2024年   1篇
  2023年   8篇
  2022年   8篇
  2021年   7篇
  2020年   16篇
  2019年   22篇
  2018年   1679篇
  2017年   1674篇
  2016年   1098篇
  2015年   61篇
  2014年   61篇
  2013年   127篇
  2012年   344篇
  2011年   1172篇
  2010年   1057篇
  2009年   801篇
  2008年   832篇
  2007年   1008篇
  2006年   14篇
  2005年   235篇
  2004年   256篇
  2003年   216篇
  2002年   89篇
  2001年   13篇
  2000年   16篇
  1999年   7篇
  1998年   1篇
  1997年   2篇
  1996年   30篇
  1994年   3篇
  1993年   2篇
  1992年   4篇
  1991年   5篇
  1990年   2篇
  1989年   2篇
  1988年   9篇
  1987年   3篇
  1984年   2篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1978年   1篇
  1977年   2篇
  1975年   1篇
  1974年   1篇
  1973年   2篇
  1972年   1篇
  1968年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
There are now three essentially separate literatures on the topics of multiple systems estimation, record linkage, and missing data. But in practice the three are intimately intertwined. For example, record linkage involving multiple data sources for human populations is often carried out with the expressed goal of developing a merged database for multiple system estimation (MSE). Similarly, one way to view both the record linkage and MSE problems is as ones involving the estimation of missing data. This presentation highlights the technical nature of these interrelationships and provides a preliminary effort at their integration.  相似文献   
103.
Abstract

In December 2012, Eric Hanson interviewed Christopher Cronin, director of technical services at the University of Chicago, about their participation as an RDA test partner and issues surrounding RDA training and implementation.  相似文献   
104.
The Lomax (Pareto II) distribution has found wide application in a variety of fields. We analyze the second-order bias of the maximum likelihood estimators of its parameters for finite sample sizes, and show that this bias is positive. We derive an analytic bias correction which reduces the percentage bias of these estimators by one or two orders of magnitude, while simultaneously reducing relative mean squared error. Our simulations show that this performance is very similar to that of a parametric bootstrap correction based on a linear bias function. Three examples with actual data illustrate the application of our bias correction.  相似文献   
105.
An empirical Bayes problem has an unknown prior to be estimated from data. The predictive recursion (PR) algorithm provides fast nonparametric estimation of mixing distributions and is ideally suited for empirical Bayes applications. This article presents a general notion of empirical Bayes asymptotic optimality, and it is shown that PR-based procedures satisfy this property under certain conditions. As an application, the problem of in-season prediction of baseball batting averages is considered. There the PR-based empirical Bayes rule performs well in terms of prediction error and ability to capture the distribution of the latent features.  相似文献   
106.
ABSTRACT

We derive an analytic expression for the bias of the maximum likelihood estimator of the parameter in a doubly-truncated Poisson distribution, which proves highly effective as a means of bias correction. For smaller sample sizes, our method outperforms the alternative of bias correction via the parametric bootstrap. Bias is of little concern in the positive Poisson distribution, the most common form of truncation in the applied literature. Bias appears to be the most severe in the doubly-truncated Poisson distribution, when the mean of the distribution is close to the right (upper) truncation.  相似文献   
107.
Estimation of finite mixture models when the mixing distribution support is unknown is an important problem. This article gives a new approach based on a marginal likelihood for the unknown support. Motivated by a Bayesian Dirichlet prior model, a computationally efficient stochastic approximation version of the marginal likelihood is proposed and large-sample theory is presented. By restricting the support to a finite grid, a simulated annealing method is employed to maximize the marginal likelihood and estimate the support. Real and simulated data examples show that this novel stochastic approximation and simulated annealing procedure compares favorably with existing methods.  相似文献   
108.
This paper explores the experiences of recent Irish highly qualified migrants who, having left post-Celtic Tiger Ireland, arrive in post-‘Peace Agreement’ Britain. Our paper contributes to understanding the enduring salience of place and how expressions of identities are framed by specific place-based factors as well as by temporality. We explore how these migrants’ narratives, as ‘successful’ professionals, are framed by complex intersections of historical legacies and changing socio-economic and intra-EU migration patterns. We consider the extent to which residual anti-Irish stereotypes remain, or indeed have re-emerged since the economic recession, and how these negative perceptions may impact on expressions of Irishness. Focusing on accents and other markers of identity, we discuss how Irishness may be constructed through a spectrum of visibilities at different times and in different places. This spatial-temporal perspective may help to go beyond a simplistic, one dimensional ethnic lens by highlighting the contextualities of identities.  相似文献   
109.
Inference in hybrid Bayesian networks using dynamic discretization   总被引:1,自引:0,他引:1  
We consider approximate inference in hybrid Bayesian Networks (BNs) and present a new iterative algorithm that efficiently combines dynamic discretization with robust propagation algorithms on junction trees. Our approach offers a significant extension to Bayesian Network theory and practice by offering a flexible way of modeling continuous nodes in BNs conditioned on complex configurations of evidence and intermixed with discrete nodes as both parents and children of continuous nodes. Our algorithm is implemented in a commercial Bayesian Network software package, AgenaRisk, which allows model construction and testing to be carried out easily. The results from the empirical trials clearly show how our software can deal effectively with different type of hybrid models containing elements of expert judgment as well as statistical inference. In particular, we show how the rapid convergence of the algorithm towards zones of high probability density, make robust inference analysis possible even in situations where, due to the lack of information in both prior and data, robust sampling becomes unfeasible.  相似文献   
110.
Multi-phase sampling (M-PhS) scheme is useful when the interest is in the estimation of the population mean of an expensive variable strictly connected with other cheaper (auxiliary) variables. The MSE is an accuracy measure of an estimator. Usually it decreases as the sample size increases. In practice the sample size cannot become arbitrarily large for possible cost constraints. From a practical point of view it would be useful to know the sample sizes which guarantee the best accuracy of the estimates for fixed costs. These “optimum” sample sizes can be, in some cases, computable but not admissible. In other cases, they can be neither admissible nor computable. The main goal of this paper is to propose a solution for both these situations. It will be clear that in both situations the solution is to consider a M-PhS scheme with one or more phases less.  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