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   89925篇
  免费   2938篇
  国内免费   4篇
管理学   12342篇
民族学   539篇
人才学   25篇
人口学   6979篇
丛书文集   518篇
教育普及   1篇
理论方法论   9396篇
综合类   2125篇
社会学   42124篇
统计学   18818篇
  2023年   504篇
  2021年   566篇
  2020年   1518篇
  2019年   2204篇
  2018年   2096篇
  2017年   3157篇
  2016年   2377篇
  2015年   2046篇
  2014年   2636篇
  2013年   18834篇
  2012年   2329篇
  2011年   2130篇
  2010年   1948篇
  2009年   2175篇
  2008年   2014篇
  2007年   1823篇
  2006年   2070篇
  2005年   2259篇
  2004年   2144篇
  2003年   1857篇
  2002年   1963篇
  2001年   1990篇
  2000年   1784篇
  1999年   1695篇
  1998年   1513篇
  1997年   1357篇
  1996年   1314篇
  1995年   1316篇
  1994年   1285篇
  1993年   1287篇
  1992年   1281篇
  1991年   1230篇
  1990年   1190篇
  1989年   1048篇
  1988年   1100篇
  1987年   1003篇
  1986年   890篇
  1985年   1064篇
  1984年   1117篇
  1983年   1018篇
  1982年   926篇
  1981年   855篇
  1980年   815篇
  1979年   871篇
  1978年   780篇
  1977年   701篇
  1976年   656篇
  1975年   633篇
  1974年   529篇
  1973年   432篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
961.
962.
This article examines the relationship between donations to the American Red Cross and the profits, sales, costs, and prices of health and safety classes offered by local chapters. Two important questions are examined: Do profits from sales of services “crowd out” donations to local chapters of the American Red Cross? Do managers respond to changes in donations by changing prices, output, or costs of saleable services? The results suggest that nonprofit managers should pay close attention to the potential impact on donations of any change in the prices charged for saleable goods and services, and that profits, costs, and prices of services are influenced by donations.  相似文献   
963.
964.
965.
The mean density of bacteria in a water body is commonly monitored using quantal assay. This paper describes the use of local scoring in estimating the spatial distribution of mean density from quantal assay results at a set of point locations. An application to estimating the mean density of fecal conform bacteria in a coastal pond is presented. Model diagnostics based on a parametric bootstrap are also presented.  相似文献   
966.
The possibility that carbon dioxide emissions from fossil fuel use might lead to global warming has become a leading environmental concern. Many scientific and environmental organizations have called for immediate action to limit carbon dioxide production. For the most part, however, public debate has focused on a single policy instrument: a carbon tax applied to fossil fuels in proportion to their carbon content. We present a detailed model of the U.S. economy and use it to compare carbon taxes with two other instruments that could achieve the same reduction in carbon dioxide emissions: a tax on the energy content of fossil fuels (a BTU tax) and an ad valorem tax on fuel use. We find that carbon taxes can achieve a given reduction with the least overall effect on the economy, but with a large effect on coal mining. Energy taxes are fairly similar to carbon taxes but have slightly less impact on coal mining and slightly greater overall cost. In contrast, ad valorem taxes fall much more lightly on coal mining but have a much greater effect on the economy as a whole.  相似文献   
967.
968.
A training project in a northern Canadian community providedan opportunity to examine participatory planning approachesand the meaning of work in First Nations communities. Focusgroups conducted three years after the unsuccessful interventionof a community economic development (CED) project suggest thatcomplex factors such as lack of support from community leadersand rate of pay for workers determine whether CED is alwaysappropriate in northern, First Nations contexts.  相似文献   
969.
Given the fragmented structure of child‐care assistance in the United States, it has been difficult to obtain accurate estimates of which families are assisted, through which mechanisms, and at what level. Making use of survey data from New York City, we analyze the distribution of several forms of public child‐care assistance. Results suggest that about 40% of all families with young children receive some form of child‐care assistance. Considering all forms of assistance, the distribution of child‐care help is targeted in both expected and some unexpected ways. Implications of these results are discussed in the context of U.S. child‐care policies governing access and benefit levels.  相似文献   
970.
The authors consider the issue of map positional error, or the difference between location as represented in a spatial database (i.e., a map) and the corresponding unobservable true location. They propose a fully model‐based approach that incorporates aspects of the map registration process commonly performed by users of geographic informations systems, including rubber‐sheeting. They explain how estimates of positional error can be obtained, hence estimates of true location. They show that with multiple maps of varying accuracy along with ground truthing data, suitable model averaging offers a strategy for using all of the maps to learn about true location.  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