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   12455篇
  免费   98篇
管理学   1741篇
民族学   128篇
人才学   1篇
人口学   2643篇
丛书文集   3篇
理论方法论   654篇
综合类   315篇
社会学   5389篇
统计学   1679篇
  2024年   2篇
  2023年   42篇
  2022年   32篇
  2021年   59篇
  2020年   113篇
  2019年   141篇
  2018年   1809篇
  2017年   1800篇
  2016年   1204篇
  2015年   121篇
  2014年   157篇
  2013年   445篇
  2012年   475篇
  2011年   1201篇
  2010年   1103篇
  2009年   835篇
  2008年   873篇
  2007年   1029篇
  2006年   43篇
  2005年   255篇
  2004年   279篇
  2003年   228篇
  2002年   109篇
  2001年   23篇
  2000年   26篇
  1999年   16篇
  1998年   16篇
  1997年   11篇
  1996年   43篇
  1995年   9篇
  1994年   9篇
  1993年   4篇
  1992年   7篇
  1991年   4篇
  1990年   1篇
  1989年   1篇
  1988年   9篇
  1987年   3篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1975年   1篇
  1974年   1篇
  1973年   2篇
  1971年   1篇
  1969年   1篇
  1968年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
191.
Response‐adaptive randomisation (RAR) can considerably improve the chances of a successful treatment outcome for patients in a clinical trial by skewing the allocation probability towards better performing treatments as data accumulates. There is considerable interest in using RAR designs in drug development for rare diseases, where traditional designs are not either feasible or ethically questionable. In this paper, we discuss and address a major criticism levelled at RAR: namely, type I error inflation due to an unknown time trend over the course of the trial. The most common cause of this phenomenon is changes in the characteristics of recruited patients—referred to as patient drift. This is a realistic concern for clinical trials in rare diseases due to their lengthly accrual rate. We compute the type I error inflation as a function of the time trend magnitude to determine in which contexts the problem is most exacerbated. We then assess the ability of different correction methods to preserve type I error in these contexts and their performance in terms of other operating characteristics, including patient benefit and power. We make recommendations as to which correction methods are most suitable in the rare disease context for several RAR rules, differentiating between the 2‐armed and the multi‐armed case. We further propose a RAR design for multi‐armed clinical trials, which is computationally efficient and robust to several time trends considered.  相似文献   
192.
The use of Bayesian nonparametrics models has increased rapidly over the last few decades driven by increasing computational power and the development of efficient Markov chain Monte Carlo algorithms. We review some applications of these models in economic applications including: volatility modelling (using both stochastic volatility models and GARCH-type models) with Dirichlet process mixture models, uses in portfolio allocation problems, long memory models with flexible forms of time-dependence, flexible extension of the dynamic Nelson-Siegel model for interest rate yields and multivariate time series models used in macroeconometrics.  相似文献   
193.
In this paper, we study space–time generalized additive models. We apply the penalyzed likelihood method to fit generalized additive models (GAMs) for nonseparable spatio-temporal correlated data in order to improve the estimation of the response and smooth terms of GAMs. The results show that our space–time generalized additive models estimated response and smooth terms reasonable well, and in addition, the mean squared error, mean absolute deviation and coverage intervals improved considerably compared to the classic GAM. An application on particulate matter concentration in the North-Italian region of Piemonte is also presented.  相似文献   
194.
Urban Ecosystems - Free-ranging domestic dogs are the world most common exotic carnivore species that could negatively interact with the native wildlife as predators, competitors, and disease...  相似文献   
195.
Control often weakens autonomy in organizational theories. While many scholars focus on the paradox of control and autonomy, few pay attention to how an organization obtains both control and autonomy. By exploring Zhangjiakou Internal Immigrant Organization, this study finds two mechanisms can contribute to the balanced combination of control and autonomy. First, managers play ambidextrous official-merchant roles, which means superiors take both bureaucratic and autonomous management styles. Second, members have dual organizational goals for both political status and network support. In conclusion, the successful combination is shaped by the subjective interaction between the government, superior managers and subordinate members.  相似文献   
196.
Larregue argued that while there is an ideological imbalance among academics that this imbalance has not unfairly impacted our findings. He also implies that it is the activism of conservatives, rather than progressives, which has created real problems in academia. As such he disputes claims that activism among progressive academics has create a backlash from political conservatives. However, Larregue does not address the previous empirical work on the subject of academic bias. Furthermore, his argument of methodological rigor does not address the tendency of scholars to overlook alternate theories. His argument that progressive scholars are no more biased than conservative scholars fails to account for the sheer number of progressive scholars relative to conservative scholars as it concerns the possibly of institutional bias. I also find his focus on fraud to be misplaced since scholars do not have to engage in fraud to be in ideological silos that do not take alternative theories into account. As to his second major argument, I am unsure whether liberal academic activism leads to conservative mistrust and await further future research on this topic. I do commend Larregue in bringing the question of sources of conservative mistust to our attention.  相似文献   
197.
How should we revise our beliefs in response to the expressed probabilistic opinions of experts on some proposition when these experts are in disagreement? In this paper I examine the suggestion that in such circumstances we should adopt a linear average of the experts’ opinions and consider whether such a belief revision policy is compatible with Bayesian conditionalisation. By looking at situations in which full or partial deference to the expressed opinions of others is required by Bayesianism I show that only in trivial circumstances are the requirements imposed by linear averaging compatible with it.  相似文献   
198.
Research on the determinants of foreign aid tends to focus on the relationship between donor country priorities and recipient state characteristics, but donors also make decisions about which organizations and programs within countries will receive assistance. Although NGOs increasingly have been recipients of foreign aid, few data are available to investigate which organizations within a given country receive that funding. Donors may prioritize structural characteristics of NGOs or their local ties—or they may seek a combination that blends concern about efficiency and accountability with an interest in developing national civil society. We use original data from Cambodia to explore whether aid is likely to go to managerial organizations (professionalized NGOs and NGOs that utilize modern management tools) or to organizations that are embedded in the domestic context. We argue that managerialism provides legitimacy for NGOs by signaling capacity and accountability to donors, increasing the likelihood of government funding. We argue that local embeddedness also confers legitimacy by aligning community ties and networks to rights-based development, increasing the likelihood of government funding. We find general support for the managerialism argument, but donor agencies do not prioritize direct funding for “indigenous” NGOs—not even among those with high levels of managerialism.  相似文献   
199.
This study employs a qualitative multiple-case study to explore relational management mechanisms for strategic nonprofit alliances (NPAs) formed by at least 3 nonprofit organizations by examining collaborative relationships among farmers associations in Taiwan. We explore these mechanisms by analyzing case data from four strategic cooperation characteristics, which can best explain NPAs. To effectively sustain partnerships, our findings suggest that an NPA applies acceptable collaborative rules and regulations, common standard procedures, symmetric information and communication, and capability building and corrective measures when cooperation involves high input commonality. The results also suggest empowerment for partners with deeper input commitment to direct decisions on resource distribution and utilization when collaborative ties involve low input measurability. Regarding high output commonality, we advise NPAs to enforce common output quality control, efficient substandard-output treatment, and external incentives as mechanisms to encourage partners for continued commitment. If relationships involve low output measurability, our findings suggest that NPAs heighten partners’ voluntary motivation for the common good, with goal-achievement assessment measures, professional certification by external experts, and acceptable and reasonable benefit-sharing methods  相似文献   
200.
Research and interventions for intimate partner violence in current use largely consist of practices aimed at getting victims to leave their abusers, rather than helping perpetrators stop their violence. In the context of parenthood, the focus on programs targeting women experiencing violence has resulted in an emphasis on mothers’ responsibility for mitigating the adverse effects of witnessing violence on children. This has led to insufficient understanding of violent men’s identities as fathers. This narrative review employed content analysis to analyze the discursive constructions of men and women as parents in a selection of peer reviewed articles about the prevention of intimate partner violence during childbearing years that were published between January 2000 and January 2015 (N = 37). A quantitative word count was conducted in order to determine the frequency with which these articles referred to men and women in their parental roles when employing prevention and intervention strategies. Women were consistently identified as mothers in all areas of the literature, while the prevalence of men’s identities as fathers was confined only to the specific, specialized area of the literature that is aimed at men alone. The implications of these findings for future research and practice in the area of prevention and intervention of intimate partner violence specifically in the context of parenthood are discussed.  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