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   7933篇
  免费   168篇
管理学   1188篇
民族学   27篇
人口学   768篇
丛书文集   26篇
理论方法论   603篇
综合类   106篇
社会学   3393篇
统计学   1990篇
  2020年   117篇
  2019年   153篇
  2018年   219篇
  2017年   274篇
  2016年   191篇
  2015年   136篇
  2014年   191篇
  2013年   1315篇
  2012年   259篇
  2011年   242篇
  2010年   178篇
  2009年   172篇
  2008年   145篇
  2007年   187篇
  2006年   162篇
  2005年   161篇
  2004年   148篇
  2003年   143篇
  2002年   151篇
  2001年   198篇
  2000年   189篇
  1999年   174篇
  1998年   129篇
  1997年   127篇
  1996年   126篇
  1995年   109篇
  1994年   105篇
  1993年   97篇
  1992年   140篇
  1991年   119篇
  1990年   117篇
  1989年   112篇
  1988年   96篇
  1987年   90篇
  1986年   95篇
  1985年   107篇
  1984年   112篇
  1983年   123篇
  1982年   98篇
  1981年   88篇
  1980年   85篇
  1979年   94篇
  1978年   90篇
  1977年   80篇
  1976年   67篇
  1975年   68篇
  1974年   58篇
  1973年   58篇
  1972年   41篇
  1971年   49篇
排序方式: 共有8101条查询结果,搜索用时 640 毫秒
911.
Engagement must be appreciated as an integral ongoing aspect of therapy. It can provide therapists with a wealth of information about the structure and functioning of the family. Engagement/counter-engagement, assessment and interventions are essential, interdependent processes which occur throughout treatment. Ways of enhancing the engagement process are discussed.  相似文献   
912.
Staudte  R.G.  Zhang  J. 《Lifetime data analysis》1997,3(4):383-398
The p-value evidence for an alternative to a null hypothesis regarding the mean lifetime can be unreliable if based on asymptotic approximations when there is only a small sample of right-censored exponential data. However, a guarded weight of evidence for the alternative can always be obtained without approximation, no matter how small the sample, and has some other advantages over p-values. Weights of evidence are defined as estimators of 0 when the null hypothesis is true and 1 when the alternative is true, and they are judged on the basis of the ensuing risks, where risk is mean squared error of estimation. The evidence is guarded in that a preassigned bound is placed on the risk under the hypothesis. Practical suggestions are given for choosing the bound and for interpreting the magnitude of the weight of evidence. Acceptability profiles are obtained by inversion of a family of guarded weights of evidence for two-sided alternatives to point hypotheses, just as confidence intervals are obtained from tests; these profiles are arguably more informative than confidence intervals, and are easily determined for any level and any sample size, however small. They can help understand the effects of different amounts of censoring. They are found for several small size data sets, including a sample of size 12 for post-operative cancer patients. Both singly Type I and Type II censored examples are included. An examination of the risk functions of these guarded weights of evidence suggests that if the censoring time is of the same magnitude as the mean lifetime, or larger, then the risks in using a guarded weight of evidence based on a likelihood ratio are not much larger than they would be if the parameter were known.  相似文献   
913.
914.
This study explored a career readiness typology of 629 8th‐grade students using the Career Factors Inventory. Data revealed developmentally appropriate elevated needs for information, specifically self‐knowledge. In addition, cluster analysis demonstrated the heterogeneity of career development needs of 8th‐grade students. Typal membership revealed little variance on sociodemographic factors. Career development implications are presented.  相似文献   
915.
Summary: The paper illustrates the value of broad researcher access to survey and administrative microdata using examples drawn from the U. S. experience, outlining how analyses of trends in earnings inequality, poverty and employment dynamics using such data have benefited policy makers and contributed to improvements in statistical agency data products. Methods of facilitating researcher access, including the release of public use files, the use of licensing agreements, and the establishment of research data centers, are discussed. * The author thanks Anne Polivka, Marilyn Seastrom and two anonymous referees for helpful comments on an earlier draft of the paper.  相似文献   
916.
917.
Critically important to Neil Smelser's theory of collective behavior is the idea that people join radical social movements because they experience strain. A social movement arises to reassure participants that something is being done to redress the underlying source of strain. Militia presence and activity on the Internet (especially Usenet) is a phenomenon that can be studied within Smelser's framework. Militia watchers contend that those who join the militias have experienced the kinds of strain to which Smelser refers. The purpose of this article is to analyze the content of Internet traffic of U.S. militias in order to test the thesis outlined above. It uses militia Web sites and militia messages posted to Usenet (N = 1,196) as primary data to test Smelser's theory. Information was gathered on 171 men and women from 28 U.S. militias who posted messages to Usenet from 1998–2001. Based on the militiamen/women studied, Smelser's thesis is generally confirmed. Most experienced some form of social stress or strain prior to or during the time that they were in the militia, and most conditions for social movement development as specified by Smelser were met and confirmed by the data.  相似文献   
918.
Goal Ambiguity in U.S. Federal Agencies   总被引:1,自引:0,他引:1  
  相似文献   
919.
Walking is a fundamental motor skill that significantly affects the level of independence in older adults. The amount of variability present in a walking pattern reflects the quality of neuromuscular control. It is well established that a large proportion of falls in older people occurs when walking. The prevention of falls is vital for minimizing disability, preventing injury, and impeding the development of frailty and subsequent deterioration in quality of life. The present literature review focuses on dynamic stability. In dynamic stability, both the base of support and the center of mass are in motion, and effective balance function is required. In general, older adults are expected to have different movement patterns from younger adults, expressed by differences in limb kinematics and kinetics. A better understanding of the biomechanical variables involved can help anticipate and prevent potential falls.  相似文献   
920.
Summary.  Many pesticide sprays that are used for crop protection are harmful to honey-bees. It can therefore be beneficial to add to the spray chemical compounds that are repellent to bees, to discourage them from feeding on recently sprayed crops. Experiments were conducted using an artificial feeding station to assess the repellent effects of various compounds. In this system, bees arrive at the feeding station, choose between feeding dishes to which different chemicals have been added, feed for a variable period and then depart. The number of bees at each feeding dish is recorded at intervals of 1 min. We discuss the analysis of data from this type of experiment, based on a queuing theory model.  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