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   91447篇
  免费   2952篇
  国内免费   3篇
管理学   12379篇
民族学   562篇
人才学   25篇
人口学   7199篇
丛书文集   529篇
教育普及   2篇
理论方法论   9469篇
现状及发展   1篇
综合类   2188篇
社会学   43146篇
统计学   18902篇
  2023年   503篇
  2021年   566篇
  2020年   1512篇
  2019年   2214篇
  2018年   2125篇
  2017年   3197篇
  2016年   2402篇
  2015年   2040篇
  2014年   2632篇
  2013年   18910篇
  2012年   2485篇
  2011年   2262篇
  2010年   2022篇
  2009年   2232篇
  2008年   2128篇
  2007年   1928篇
  2006年   2138篇
  2005年   2336篇
  2004年   2219篇
  2003年   1934篇
  2002年   2029篇
  2001年   2039篇
  2000年   1809篇
  1999年   1706篇
  1998年   1512篇
  1997年   1368篇
  1996年   1315篇
  1995年   1338篇
  1994年   1325篇
  1993年   1298篇
  1992年   1307篇
  1991年   1228篇
  1990年   1203篇
  1989年   1038篇
  1988年   1127篇
  1987年   1008篇
  1986年   914篇
  1985年   1082篇
  1984年   1136篇
  1983年   1021篇
  1982年   946篇
  1981年   865篇
  1980年   823篇
  1979年   868篇
  1978年   776篇
  1977年   715篇
  1976年   661篇
  1975年   638篇
  1974年   516篇
  1973年   440篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Acculturative stress in the adjustment of immigrant families   总被引:1,自引:0,他引:1  
This study reviews the issue of acculturative stress in immigrant families. Acculturative stress includes behaviors experienced by immigrants that are a direct consequence of the process of acculturation and adaptation to a new society. A number of stressors impacting on the acculturation of immigrant families is discussed. These stressors include lack of English language skills, employment and economic status, educational background, family life, and sociopolitical and immigration status.  相似文献   
112.
A class of symmetric bivariate uniform distributions is proposed for use in statistical modeling. The distributions may be constructed to be absolutely continuous with correlations as close to±1 as desired. Expressions for the correlations, regressions and copulas are found. An extension to three dimensions is proposed.  相似文献   
113.
The product of two independent or dependent scalar normal variables, sums of products, sample covariances, and general bilinear forms are considered. Their distributions are shown to belong to a class called generalized Laplacian. A growth-decay mechanism is also shown to produce such a generalized Laplacian. Sets of necessary and sufficient conditions are derived for bilinear forms to belong to this class. As a generalization, the distributions of rectangular matrices associated with multivariate normal random vectors are also discussed.  相似文献   
114.
115.
Abstract Rural sociology is intrinsically concerned with the spatial dimensions of social life. However, this underlying research tradition, particularly the use of space as a research strategy, has been insufficiently addressed and its contributions to general sociology are little recognized. I outline how concern with space, uneven development, and the social relationships of peripheral settings have provided substantive boundary and conceptual meaning to rural sociology, propelled its evolution, and left it with a legacy of strengths, weaknesses, and challenges. A willingness to tackle the dimension of space and the thorny problems it raises often sets rural sociologists apart from other sociologists. This research tradition contrasted with general sociology's concern with developing generalization, aspatial covering laws, and proto-typical relationships of modern or Fordist development settings. Conceptual openings have left sociologists questioning their past agenda. Coupled with the “creative marginality” inherent in the questions and contexts addressed by rural sociologists, this makes the subfield central to contemporary sociology.  相似文献   
116.
117.
To study the homogeneity and influences on scientists'perspectives of environmental risks, we have examined similarities and differences in risk perceptions, particularly regarding nuclear wastes, and policy preferences among 1011 scientists and engineers. We found significant differences ( p 0.05)in the patterns of beliefs among scientists from different fields of research. In contrast to physicists, chemists, and engineers, life scientists tend to: (a)perceive the greatest risks from nuclear energy and nuclear waste management; (b)perceive higher levels of overall environmental risk; (c)strongly oppose imposing risks on unconsenting individuals; and (d)prefer stronger requirements for environmental management. On some issues related to priorities among public problems and calls for government action, there are significant variations among life scientists or physical scientists. We also found that–independently of field of research–perceptions of risk and its correlates are significantly associated with the type of institution in which the scientist is employed. Scientists in universities or state and local governments tend to see the risks of nuclear energy and wastes as greater than scientists who work as business consultants, for federal organizations, or for private research laboratories. Significant differences also are found in priority given to environmental risks, the perceived proximity of environmental disaster, willingness to impose risks on an unconsenting population, and the necessity of accepting risks and sacrifices.  相似文献   
118.
The simple logistic regression model with normal measurement error and normal regressor is shown to be identifiable without any extra information about the measurement error. The multiple logistic regression model with more than one regressor variable measured with error is not identifiable. If the covariance matrix of the measurement error is known up to a scalar factor, the model is identified. Further we discuss why in spite of the identifiability the models cannot be estimated in a reasonable way without extra information about the measurement error.  相似文献   
119.
On the run length of a Shewhart chart for correlated data   总被引:1,自引:0,他引:1  
We consider an extension of the classical Shewhart control chart to correlated data which was introduced by Vasilopoulos/Stamboulis (1978). Inequalities for the moments of the run length are given under weak conditions. It is proved analytically that the average run length (ARL) in the in-control state of the correlated process is larger than that in the case of independent variables. The exact ARL is calculated for exchangeable normal variables and autoregressive processes (AR). Moreover, we compare this chart with residual charts. Especially, in the case of an AR(1)—process with positive coefficient, it turns out that the out-of-control ARL of the modified Shewhart chart is smaller than that of the Shewhart chart for the residuals.  相似文献   
120.
We present a new characterization technique extracted from a well known idea in statistical inference. We use the partial derivative of the logarithm of the survival function in connection with truncated moments to characterize several probability distributions. Our methods introduce a unified technique to obtain several well known results in a unified way.  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