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   7047篇
  免费   243篇
管理学   826篇
民族学   29篇
人才学   3篇
人口学   699篇
丛书文集   26篇
教育普及   1篇
理论方法论   708篇
综合类   66篇
社会学   3748篇
统计学   1184篇
  2023年   63篇
  2021年   59篇
  2020年   111篇
  2019年   143篇
  2018年   175篇
  2017年   256篇
  2016年   177篇
  2015年   121篇
  2014年   212篇
  2013年   1678篇
  2012年   219篇
  2011年   212篇
  2010年   170篇
  2009年   136篇
  2008年   178篇
  2007年   173篇
  2006年   186篇
  2005年   142篇
  2004年   142篇
  2003年   95篇
  2002年   127篇
  2001年   150篇
  2000年   145篇
  1999年   155篇
  1998年   127篇
  1997年   96篇
  1996年   114篇
  1995年   84篇
  1994年   78篇
  1993年   111篇
  1992年   113篇
  1991年   119篇
  1990年   91篇
  1989年   90篇
  1988年   70篇
  1987年   76篇
  1986年   69篇
  1985年   80篇
  1984年   73篇
  1983年   77篇
  1982年   51篇
  1981年   58篇
  1980年   45篇
  1979年   51篇
  1978年   43篇
  1977年   38篇
  1976年   37篇
  1975年   35篇
  1974年   42篇
  1973年   31篇
排序方式: 共有7290条查询结果,搜索用时 707 毫秒
51.
The effects of sectoral shifts, measured by dispersion in the growth rates of employment or earning across industries or regions, on unemployment are tested in a specification controlling for the effects of other labor-market variables and shifts in the demographic composition of the labor force. Interindustry and geographical shifts in labor demand have significant unemployment effects, with adult males the group most strongly affected. The estimated equations imply that most of the fluctuation in unemployment over the period 1956-87 was been due to microeconomic causes rather than aggregate demand.  相似文献   
52.
53.
Unions,PAC contributions,and the NAFTA vote   总被引:1,自引:0,他引:1  
Political action committees (PACs), especially those controlled by organized labor and business, have been shown to affect Congressional voting. We explore how PACs influenced the House of Representatives’ vote on the North American Free Trade Agreement (NAFTA). The NAFTA vote is analyzed because organized labor strongly opposed the treaty while business generally supported it and because of the straight-forward voting generated by its fast-track status. Probit analysis of a unique, unpublished data set containing information about PAC and non-PAC contributions to the 1992 House election campaigns demonstrates that Representatives who depended largely on labor PACs tended to oppose NAFTA, while Representatives who derived a large proportion of their campaign contributions from business PACs tended to favor its passage.  相似文献   
54.
The goal of Louisiana's 1990–1991 comparative risk project, also called the Louisiana Environmental Action Plan (LEAP), was to incorporate risk assessment into state environmental planning and policymaking. Scientists, government officials, and citizens were brought together to estimate the relative risk to human health, natural resources, and quality of life posed by 33 selected environmental issues. The issues were then ranked according to their relative estimated risks. It was hoped that this ranking of "comparative risks" would enable state policymakers to target the most important environmental problems and allocate scarce public resources more rationally and efficiently. As a result of the project, the governor issued an Executive Order forming a permanent Public Advisory Committee to continue this type of comparative risk assessment in Louisiana.  相似文献   
55.
Native American drinking: a neglected subject of study and research   总被引:1,自引:0,他引:1  
Although Native Americans are plagued by high rates of alcoholism, violence, suicide and early death, these social and clinical problems are usually given little more than cursory treatment in textbooks. A content analysis of twenty-six textbooks on alcoholism and substance misuse revealed that only four provided a detailed discussion of Native American drinking. Greater attention needs to be given to the cultural, psychological, and biological issues of drinking and drunkenness among this special population.  相似文献   
56.
The EM algorithm is a popular method for maximizing a likelihood in the presence of incomplete data. When the likelihood has multiple local maxima, the parameter space can be partitioned into domains of convergence, one for each local maximum. In this paper we investigate these domains for the location family generated by the t-distribution. We show that, perhaps somewhat surprisingly, these domains need not be connected sets. As an extreme case we give an example of a domain which consists of an infinite union of disjoint open intervals. Thus the convergence behaviour of the EM algorithm can be quite sensitive to the starting point.  相似文献   
57.
Preface     
  相似文献   
58.
The present study was conducted to assess differences in the behavioral and demographic characteristics of snuff (dip) users as compared to users of chewing tobacco. High School football players (1116) were surveyed concerning their use and perceptions of smokeless tobacco. Adolescent athletes who tried smokeless tobacco were more likely to be white, to use cigarettes, alcohol, and cigars and to have family users than those who never tried. Initial use was highest before the age of fourteen years and was influenced by friends, curiosity and family. Dippers tended to initiate use because of friends, while chewers started because of family users. Users of both dip and chew started primarily because of curiosity. Users of both were more likely to consume greater amounts to alcohol and cigarettes and to smoke cigars and pipes. It appears that the longer smokeless tobacco is consumed, the more likely both dip and chew will be used. Users of smokeless tobacco for more than two years tended to consume more of the product each week, used it for more hours/day, initiated use at an earlier age, and used it more often at school and work than those using it for less than two years. Use of cigars/pipes, consumption of alcohol, and quantity of cigarette consumption increased significantly with longer duration of smokeless tobacco use. Intervention and prevention programs would be helped by understanding differences between users of various smokeless tobacco products and differences related to the duration of use. In addition, further analyses of smokeless tobacco users should study chewers, dippers, and users of both separately.  相似文献   
59.
60.
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