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   23439篇
  免费   820篇
  国内免费   282篇
管理学   377篇
劳动科学   5篇
民族学   414篇
人才学   2篇
人口学   579篇
丛书文集   2853篇
理论方法论   1550篇
综合类   15351篇
社会学   2009篇
统计学   1401篇
  2024年   45篇
  2023年   184篇
  2022年   219篇
  2021年   312篇
  2020年   402篇
  2019年   454篇
  2018年   409篇
  2017年   497篇
  2016年   466篇
  2015年   612篇
  2014年   1635篇
  2013年   2308篇
  2012年   1869篇
  2011年   1884篇
  2010年   1616篇
  2009年   1424篇
  2008年   1452篇
  2007年   1324篇
  2006年   1289篇
  2005年   1221篇
  2004年   1251篇
  2003年   1145篇
  2002年   913篇
  2001年   762篇
  2000年   438篇
  1999年   123篇
  1998年   52篇
  1997年   39篇
  1996年   31篇
  1995年   28篇
  1994年   22篇
  1993年   25篇
  1992年   12篇
  1991年   8篇
  1990年   6篇
  1989年   10篇
  1988年   8篇
  1986年   4篇
  1985年   6篇
  1984年   8篇
  1983年   4篇
  1982年   4篇
  1981年   9篇
  1980年   3篇
  1979年   4篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
291.
This study examined the indigenous cultural practices that impact the well-being of children and families at five sites in Nigeria. Fifteen community leaders participated in semi-structured interviews, and 78 community members participated in focus group discussions in their communities. Responses were analyzed using a grounded theory and thematic analysis approach. Three cultural practices are discussed: the naming ceremony of the child, the use of Oríkì, and the care of children and family by relatives. Overall, the cultural practices largely reflected the indigenous knowledge and beliefs of the local context. Implications for social work are discussed.  相似文献   
292.
This article traces the development of the Chinese social media app WeChat from its origins to its current role as a leading communications tool for some 600 million Chinese citizens. It analyzes the ways the small-group oriented app is changing China’s social connections, as it enhances trusted, personal contacts while transforming opportunities for larger online group formation. The article assesses methods the Chinese Government employs to monitor and control WeChat communication, and provides a case-focus study. It also considers the apolitical features, in particular, those related to entertainment and personal social relations, which have made important contributions to WeChat’s great popularity.  相似文献   
293.
Youth’s perceptions of peer norms have profound effects on their attitudes and behaviors. Unfortunately, their perceptions of peers tend to be biased. To investigate the role of media in the formation of misperceived peer norms, the current study tested and compared two media-effect mechanisms: the direct exemplar mechanism and the indirect influence of presumed influence (IPI) mechanism. The two mechanisms were tested in a sample (n = 1746) that is representative of college students in one large university in China, based on which the actual and perceived campus smoking rates were examined. The individual-level perceived peer smoking prevalence was then analyzed in comparison with the campus-level actual smoking prevalence. The results revealed serious overestimations of peer smoking prevalence. As predicted, pro-smoking media content significantly heightened smoking prevalence estimates through both exemplar and IPI mechanisms. In contrast, anti-smoking messages did not elicit any intended effect through the IPI mechanism, but showed a boomerang effect through the exemplar mechanism. These findings suggest that both pro- and anti-smoking media content may be responsible for inflated perceptions of peer smoking among youth.  相似文献   
294.
Objectives: The aim of the current article was to provide an overview of literature on sexual function and sexual difficulties in older adults. Method: The authors conducted a narrative review of papers published in English between January 2005 and July 2015 based on an extensive search in PsycINFO. Results: The review showed that although common biological changes may adversely affect sexual function in old age, sexual experience seems to also be affected by psychological and interpersonal factors. Conclusions: Greater life expectancy and better medical care will result in older individuals with chronic diseases living longer. The need for help to cope with changes in sexual health is likely to increase in older adults, as sexuality may be negatively affected through several pathways.  相似文献   
295.
This study explores the impacts of HIV pre-exposure prophylaxis (PrEP) use on the sexual health of men who have sex with men (MSM). The authors conducted in-depth interviews with MSM who use PrEP (n = 14). Data was analyzed using interpretative phenomenological analysis. PrEP use reduced fear and shame associated with sex and facilitated greater sexual satisfaction and intimacy. Although participants generally viewed PrEP as empowering and beneficial, they also experienced PrEP-related stigma. The authors’ analysis emphasizes the importance of understanding the reasons MSM use PrEP and highlights opportunities for reducing harm and fostering sexual health among MSM who are using or considering PrEP.  相似文献   
296.
In a recent article from the Annals of Applied Statistics, Cox discussed the main phases of applied statistical research ranging from clarifying study objectives to final data analysis and interpreting results. As an incidental remark to these main phases, we advocate that beyond cleaning and preprocessing the data, it is a good practice to audit the data to determine if they can be trusted at all. A case study based on Ghanaian Official Fishery Statistics is used to illustrate this need, with Benford's law being the tool used to carrying out the data audit. Supplementary materials for this article are available online.  相似文献   
297.
Various statistical tests have been developed for testing the equality of means in matched pairs with missing values. However, most existing methods are commonly based on certain distributional assumptions such as normality, 0-symmetry or homoscedasticity of the data. The aim of this paper is to develop a statistical test that is robust against deviations from such assumptions and also leads to valid inference in case of heteroscedasticity or skewed distributions. This is achieved by applying a clever randomization approach to handle missing data. The resulting test procedure is not only shown to be asymptotically correct but is also finitely exact if the distribution of the data is invariant with respect to the considered randomization group. Its small sample performance is further studied in an extensive simulation study and compared to existing methods. Finally, an illustrative data example is analysed.  相似文献   
298.
299.
This article deals with the estimation of R = P{X < Y}, where X and Y are independent random variables from geometric and exponential distribution, respectively. For complete samples, the MLE of R, its asymptotic distribution, and confidence interval based on it are obtained. The procedure for deriving bootstrap-p confidence interval is presented. The UMVUE of R and UMVUE of its variance are derived. The Bayes estimator of R is investigated and its Lindley's approximation is obtained. A simulation study is performed in order to compare these estimators. Finally, all point estimators for right censored sample from the exponential distribution, are obtained.  相似文献   
300.
In many industrial and natural phenomena, we need the probability that a component is smaller than the other component. Under a stress–strength model, this is reliability of an item. Under independent setup, there are different approaches for the estimation of such reliability. Here, estimation is considered under the dependent case. Under bi-variate setup uniformly minimum variance unbiased estimator is obtained. Also comparison with available estimator based on Maximum Likelihood Estimate (MLE) is done through Mean Square Error (MSE) and bias. Also these are compared by computing L1 distance between their distribution functions. From this idea and numerical computations, UMVUE appears to be good.  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