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   86230篇
  免费   2917篇
  国内免费   3篇
管理学   11959篇
民族学   521篇
人才学   25篇
人口学   6418篇
丛书文集   501篇
理论方法论   9173篇
综合类   2038篇
社会学   39962篇
统计学   18553篇
  2023年   500篇
  2021年   557篇
  2020年   1488篇
  2019年   2185篇
  2018年   1984篇
  2017年   3055篇
  2016年   2298篇
  2015年   2028篇
  2014年   2608篇
  2013年   18755篇
  2012年   2159篇
  2011年   1953篇
  2010年   1857篇
  2009年   2124篇
  2008年   1914篇
  2007年   1702篇
  2006年   1984篇
  2005年   2170篇
  2004年   2064篇
  2003年   1800篇
  2002年   1891篇
  2001年   1858篇
  2000年   1647篇
  1999年   1577篇
  1998年   1440篇
  1997年   1286篇
  1996年   1245篇
  1995年   1276篇
  1994年   1246篇
  1993年   1229篇
  1992年   1189篇
  1991年   1123篇
  1990年   1100篇
  1989年   943篇
  1988年   1045篇
  1987年   919篇
  1986年   811篇
  1985年   988篇
  1984年   1060篇
  1983年   943篇
  1982年   889篇
  1981年   821篇
  1980年   771篇
  1979年   817篇
  1978年   733篇
  1977年   663篇
  1976年   623篇
  1975年   599篇
  1974年   484篇
  1973年   408篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
111.
112.
113.
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   
114.
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   
115.
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   
116.
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   
117.
118.
119.
120.
What do voters really know about party platforms and how do they perceive the contents? Are there any relationships between party election platforms and electoral behavior? Despite of much research on parties, there are hardly any answers to these questions. If political parties devise programmes in order to influence political attitudes or electoral behavior, it will be necessary that these programmes are read by people. But it seems to be unclear if and how people do so. This article shows clearly that voters don’t know much about party manifestoes. Still, programmes are more important for voters than many people believe. Programmes are also an important factor for electoral behavior. But there is still a lack of data to get evident results.  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