全文获取类型
收费全文 | 17734篇 |
免费 | 451篇 |
专业分类
管理学 | 2432篇 |
民族学 | 84篇 |
人才学 | 3篇 |
人口学 | 1583篇 |
丛书文集 | 104篇 |
教育普及 | 2篇 |
理论方法论 | 1835篇 |
综合类 | 383篇 |
社会学 | 8893篇 |
统计学 | 2866篇 |
出版年
2021年 | 85篇 |
2020年 | 266篇 |
2019年 | 322篇 |
2018年 | 331篇 |
2017年 | 495篇 |
2016年 | 416篇 |
2015年 | 322篇 |
2014年 | 381篇 |
2013年 | 2921篇 |
2012年 | 541篇 |
2011年 | 462篇 |
2010年 | 335篇 |
2009年 | 368篇 |
2008年 | 410篇 |
2007年 | 435篇 |
2006年 | 362篇 |
2005年 | 494篇 |
2004年 | 449篇 |
2003年 | 417篇 |
2002年 | 441篇 |
2001年 | 452篇 |
2000年 | 406篇 |
1999年 | 422篇 |
1998年 | 304篇 |
1997年 | 294篇 |
1996年 | 293篇 |
1995年 | 270篇 |
1994年 | 284篇 |
1993年 | 268篇 |
1992年 | 298篇 |
1991年 | 309篇 |
1990年 | 269篇 |
1989年 | 272篇 |
1988年 | 258篇 |
1987年 | 232篇 |
1986年 | 234篇 |
1985年 | 231篇 |
1984年 | 262篇 |
1983年 | 249篇 |
1982年 | 218篇 |
1981年 | 183篇 |
1980年 | 178篇 |
1979年 | 209篇 |
1978年 | 176篇 |
1977年 | 161篇 |
1976年 | 143篇 |
1975年 | 140篇 |
1974年 | 125篇 |
1973年 | 120篇 |
1971年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
151.
The authors consider Bayesian analysis for continuous‐time Markov chain models based on a conditional reference prior. For such models, inference of the elapsed time between chain observations depends heavily on the rate of decay of the prior as the elapsed time increases. Moreover, improper priors on the elapsed time may lead to improper posterior distributions. In addition, an infinitesimal rate matrix also characterizes this class of models. Experts often have good prior knowledge about the parameters of this matrix. The authors show that the use of a proper prior for the rate matrix parameters together with the conditional reference prior for the elapsed time yields a proper posterior distribution. The authors also demonstrate that, when compared to analyses based on priors previously proposed in the literature, a Bayesian analysis on the elapsed time based on the conditional reference prior possesses better frequentist properties. The type of prior thus represents a better default prior choice for estimation software. 相似文献
152.
We present a case study based on a depression study that will illustrate the use of Bayesian statistics in the economic evaluation of cost‐effectiveness data, demonstrate the benefits of the Bayesian approach (whilst honestly recognizing any deficiencies) with respect to frequentist methods, and provide details of using the methods, including computer code where appropriate. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
153.
经济系统的演化与政策作用 总被引:1,自引:0,他引:1
该文根据耗散结构的基本原理 ,将经济系统划分为平衡态、过渡态和自组织状态。并将政策因素看成是一种外部调控手段 ,分析了在经济系统的不同状态下 ,政策因素对改变系统的结构及变化趋势所起的不同作用 相似文献
154.
155.
该文分析了法国会计模式的特点和影响因素 ,认为法国会计模式与中国会计模式存在相似之处 ,并借鉴法国 1 996年以来会计改革的经验 ,对完善我国会计模式提出了建议 相似文献
156.
James P. McDermott G. Jogesh Babu John C. Liechty Dennis K. J. Lin 《Statistics and Computing》2007,17(4):311-321
We consider the problem of density estimation when the data is in the form of a continuous stream with no fixed length. In
this setting, implementations of the usual methods of density estimation such as kernel density estimation are problematic.
We propose a method of density estimation for massive datasets that is based upon taking the derivative of a smooth curve
that has been fit through a set of quantile estimates. To achieve this, a low-storage, single-pass, sequential method is proposed
for simultaneous estimation of multiple quantiles for massive datasets that form the basis of this method of density estimation.
For comparison, we also consider a sequential kernel density estimator. The proposed methods are shown through simulation
study to perform well and to have several distinct advantages over existing methods. 相似文献
157.
John Urry 《全球网;跨国事务杂志》2004,4(2):109-130
Abstract In this article I explore the increasing overlaps between ‘sociology’ and ‘physics’ through analysing recent contributions to the social network literature concerned with exploring and explaining the so‐called ‘small world’ phenomenon. I show that this new social network literature, while very provocative, is insufficiently sociological and insufficiently complex. With regard to the former it is demonstrated that a key issue is that of meetingness and hence of travel in order to effect meetingness. Networks have, in other words, to be performed, and they have to come together from time to time, especially to talk. I further show that the small worlds literature is insufficiently complex. Social networks often involve combinations of mobilities and highly structured material immobilities. I conclude the article with an analysis of how a new ‘social physics’ based around the notion of ‘network’ might be established in an era in which time and space seem increasingly warped, bent and twisted into strikingly new topologies. 相似文献
158.
Stevan Harnad Tim Brody Franois Vallires Les Carr Steve Hitchcock Yves Gingras Charles Oppenheim Heinrich Stamerjohanns Eberhard R. Hilf 《Serials Review》2004,30(4):310-314
The research access/impact problem arises because journal articles are not accessible to all of their would-be users; hence, they are losing potential research impact. The solution is to make all articles Open Access (OA; i.e., accessible online, free for all). OA articles have significantly higher citation impact than non-OA articles. There are two roads to OA: the “golden” road (publish your article in an OA journal) and the “green” road (publish your article in a non-OA journal but also self-archive it in an OA archive). Only 5% of journals are gold, but over 90% are already green (i.e., they have given their authors the green light to self-archive); yet only about 10–20% of articles have been self-archived. To reach 100% OA, self-archiving needs to be mandated by researchers' employers and funders, as the United Kingdom and the United States have recently recommended, and universities need to implement that mandate. 相似文献
159.
John Richens John Imrie Helen Weiss 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2003,166(2):207-215
Summary. The cumulative number of human immunodeficiency virus (HIV) infections worldwide has reached 60 million in little over 30 years. HIV continues to spread despite a detailed understanding of the manner in which it spreads and measures which can prevent spread. Some governments have been highly successful in containing the spread of HIV through blood products and from mother to child and among injecting drug users. Lack of political will, lack of resources or challenges to widely accepted scientific evidence have held back similar interventions in other countries. It has proved much more difficult to reduce the sexual transmission of HIV in both high and low income countries. A wide range of strategies has been identified but it remains unclear which strategies deserve priority and what methods of promoting them have the greatest effect. There is ample evidence that awareness of HIV and changes in sexual behaviour have occurred widely but the penetration of information remains poor in some vulnerable groups especially adolescents and women in poorer countries. Further obstacles face those who have information about the risk. The subordinate position of women and a desire for large families are important obstacles to condom negotiation and use. Urbanization, poverty, conflict and declining public services all exacerbate unsafe sexual behaviour. We argue that so-called 'structural' interventions directed at these wider contexts of unsafe behaviour merit greater attention. Such approaches have the added benefit of being less susceptible to 'risk compensation' which has the potential to undermine strategies directed at reducing the transmission efficiency of HIV. 相似文献
160.
Louise Townson Sue Macauley Elizabeth Harkness Andy Docherty John Dias Malcolm Eardley Rohhss Chapman 《Disability & Society》2007,22(5):523-536
This article presents the findings of a qualitative research project about the difficulties in accessing advocacy faced by adults labelled as having autism and Asperger's Syndrome in the Northwest of England. It is also an example of partnership working between three organisations. The article examines both the process of team-led (emancipatory) research and the project findings. Seven main themes emerged throughout the research: late diagnosis and lack of service support; bad experiences with systems of care; feelings of 'not belonging' (identity issues); barriers around communication and sensitivity towards individuals; lack of awareness and access to advocacy and rights; difficulties of 'fitting into' what is already available; and interest in developing knowledge around advocacy. Examination of the main themes pointed to a disturbing link between poor service response, episodes of crisis and mental ill health. The Carlisle People First Research Team is made up of 6 researchers who are labelled as having 'learning difficulties' who work in partnership with one other researcher. 相似文献