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   1193篇
  免费   90篇
  国内免费   1篇
管理学   57篇
民族学   9篇
人口学   11篇
丛书文集   35篇
理论方法论   137篇
综合类   310篇
社会学   320篇
统计学   405篇
  2024年   1篇
  2023年   22篇
  2022年   2篇
  2021年   12篇
  2020年   47篇
  2019年   60篇
  2018年   51篇
  2017年   69篇
  2016年   28篇
  2015年   37篇
  2014年   52篇
  2013年   277篇
  2012年   44篇
  2011年   39篇
  2010年   54篇
  2009年   43篇
  2008年   39篇
  2007年   35篇
  2006年   39篇
  2005年   40篇
  2004年   50篇
  2003年   37篇
  2002年   25篇
  2001年   24篇
  2000年   20篇
  1999年   20篇
  1998年   11篇
  1997年   14篇
  1996年   13篇
  1995年   8篇
  1994年   12篇
  1993年   11篇
  1992年   8篇
  1991年   4篇
  1990年   4篇
  1989年   5篇
  1988年   4篇
  1987年   1篇
  1986年   3篇
  1985年   5篇
  1984年   1篇
  1983年   3篇
  1981年   4篇
  1980年   2篇
  1979年   2篇
  1977年   2篇
排序方式: 共有1284条查询结果,搜索用时 31 毫秒
971.
“羾得N”和“在N”同为湖南湘潭方言中的体标记。其中“羾”与“在”都能作动词、介词,前者强调动态义,只能接处所宾语,不能接时间宾语,后者则可接处所或时间宾语。比较“羾得N”和“在N”,前者在句法配置上只能位于动词性结构之前,语义上只表进行义,语用功能上多用于随意场合,虚化程度较低;后者则可以位于动词性结构之前或之后,可表进行义或持续义,语用场合不限,虚化程度比前者稍高。  相似文献   
972.
In this article, we investigate a central limit theorem for weighted sum of independent random variables under sublinear expectations. It is turned out that our results are natural extensions of the results obtained by Peng (2008 Peng , S. (2008). A New Central Limit Theorem under Sublinear Expectations. arXiv:0803. 2656vl [math.PR]. [Google Scholar]) and Li and Shi (2010 Li , M. , Shi , Y. ( 2010 ). A general central limit theorem under sublinear expectations . Sci. China Ser. A 53 : 19891994 .[Crossref] [Google Scholar]).  相似文献   
973.
We consider the estimation of the parameters in two partitioned linear models, denoted by 𝒜 = {y, X 1 β 1 + X 2 β 2, V 𝒜} and ? = {y, X 1 β 1 + X 2 β 2, V ?}, which we call full models. Correspondingly, we define submodels 𝒜1 = {y, X 1 β 1, V 𝒜} and ?1 = {y, X 1 β 1, V ?}. Using the so-called Pandora's Box approach introduced by Rao (1971 Rao , C. R. ( 1971 ). Unified theory of linear estimation . Sankhy?, Ser. A 33 : 371394 . [Corrigendum (1972), 34, p. 194, 477.]  [Google Scholar], we give new necessary and sufficient conditions for the equality between the best linear unbiased estimators (BLUEs) of X 1 β 1 under 𝒜1 and ?1 as well as under 𝒜 and ?. In our considerations we will utilise the Frisch–Waugh–Lovell theorem which provides a connection between the full model 𝒜 and the reduced model 𝒜 r  = {M 2 y, M 2 X 1 β 1, M 2 V 𝒜 M 2} with M 2 being an appropriate orthogonal projector. Moreover, we consider the equality of the BLUEs under the full models assuming that they are equal under the submodels.  相似文献   
974.
信息科学的进步如何影响统计学理论与方法的发展,是21世纪大数据时代统计学面临的重要问题。回顾20世纪40年代MCMC方法的起源与发展,基于千岛湖植物考察与R软件直观性解释Metropolis–Hastings算法,讨论MCMC方法的发展对现代贝叶斯统计复兴具有至关重要的作用。基于云计算随机模拟,统计学与信息科学密切结合、贝叶斯与频率统计相互交融的统计分析新范式,可能成为大数据研究的新思路。  相似文献   
975.
Since 1981 close to forty countries have introduced systemic pension reforms that have replaced all or part of prior pay‐as‐you‐go (PAYG) schemes with privately managed funded defined contribution (FDC) pillars or systems. However, over the past decade about half of these countries have subsequently cutback on, or entirely eliminated, these FDC schemes. In this article we explore some of the reasons why this reversal is often taking place in developing countries. As part of our analysis we propose a new pension reform typology that goes beyond the commonly used dichotomy between PAYG and pension privatization. We identify and discuss four factors that are of particular relevance to those seeking to understand the pension policy reversals that have been taking place in many developing countries: low pension coverage and incentive incompatibility, triple burden costs, tradeoffs between pension reforms and social pensions, and difficulties with annuitization.  相似文献   
976.
The United States is at a crossroads in its policies for families and women. Currently, the United States provides basic support for children, fathers, and mothers in the form of unpaid parental leave, child‐related tax breaks, and limited public child care. In contrast, the other member states of the Organisation for Economic Co‐operation and Development (OECD) empower families through paid parental leave and comprehensive investments in infants and children. The potential gains from strengthening these policies in the United States are enormous. Paid parental leave and subsidized child‐care help to get and keep more women in the workforce, contribute to economic growth, offer cognitive and health benefits to children, and give parents options in defining their preferred work‐life strategy. Indeed, the United States has been falling behind the rest of the OECD in many social and economic indicators by not adequately investing in children, fathers and mothers. Given the significant payoffs to these family supports, this article focuses on issues of reconciling work and care commitments for families with young children, and, in particular, on paid parental leave policies within the OECD and the United States.  相似文献   
977.
虽有研究对兼并标的资产价值服从连续随机分布情形下交易价格确定问题进行了讨论,但对离散随机分布情形下交易价格确定问题的讨论不够深入,这就不仅仅使得研究与实践相互脱节,更降低了研究对现实的解释力。现在对一类标的资产价值服从二叉树离散分布情形下交易价格问题进行研究,运用实物期权理论和博弈论的研究方法对标的价值评估与交易价格确定分别进行了讨论。研究运用中心极限定理分析了标的资产价值呈现二叉树特征,并且存在无限次上涨与下降状态情形下实物期权的极限分布。然后在对著名的Rubinstein讨价还价定理进行改进的基础上,给出了离散二叉树分布情形下的标的资产交易价格确定的解析表达式。最后,通过数值仿真揭示不同参数变化所引起的交易价格变化趋势,从而进一步说明模型的合理性和对现实的解释力。  相似文献   
978.
This article reviews the recent literature on existing mechanisms that allow for the portability of social security entitlements for migrant workers and finds that North–North migrants have the best access to portability. There is limited coordination between origin and destination countries regarding the portability of social entitlements of South–North migrants. These migrants are dealing with discourses and policies that treat them as second class citizens, even as they are providing much‐needed labour to their host countries. South–South migrants are seeing new regional mechanisms addressing portability. However, many of the impacts of these mechanisms are not yet known. Other knowledge gaps on portability relate to internal and South–South migration, the role of gender and other social identities, migrants’ occupations as well as their legal immigration status.  相似文献   
979.
Longevity insurance annuities are deferred annuities that begin payment at advanced older ages, such as at age 80. Such annuities would benefit some older retirees who have drawn down their savings, but the private sector has problems in providing them. Originally, social insurance old‐age benefits programmes in some countries were structured as longevity insurance programmes, with 50 per cent or less of those entering the workforce surviving to receive the benefits. Over time, however, as life expectancy has improved, the benefits these programmes provide have slowly transformed into benefits that most people entering the workforce ultimately receive. This article argues that the reintroduction of longevity insurance benefits as part of social insurance old‐age benefit programmes could be an important policy innovation, in particular because this benefit is generally not provided by the private sector. China has introduced longevity insurance benefits as part of its social insurance system, offering a model for other countries, particularly those providing modest social insurance old‐age benefits.  相似文献   
980.
Mongolia achieved high population coverage under mandatory health insurance relatively quickly. This fact was viewed by policy‐ and decision‐makers as a central issue for health financing reform in Mongolia. Health insurance brought many new features for health service planning, provision, funding and resource management. Based on initial achievements, health insurance came to be strategically considered as the vehicle for achieving universal coverage. The article analyses developments in Mongolia's health insurance over the last decade along with the core policy dimensions of Universal Health Coverage. It examines various reform approaches and the numerous amendments to laws that have been implemented during this period and discusses new opportunities as well as challenges. The analytical review and findings discussed suggest that Mongolia has a need for evidence‐based policy decisions and informed political support, with health insurance backed by robust institutional and administrative capacities. More generally, it also emphasizes that health policy goals and objectives can be attained by strengthening and making transparent and publicly‐accountable all health system financing functions and arrangements. The policy analysis, experiences, lessons and proposed strategies presented with regard to Mongolia intend to stimulate wider discussions on health insurance development as well as promote continuing focused research on specific aspects of health insurance and public financing reform.  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