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   8226篇
  免费   221篇
管理学   1256篇
民族学   53篇
人才学   3篇
人口学   758篇
丛书文集   63篇
理论方法论   904篇
综合类   72篇
社会学   4276篇
统计学   1062篇
  2021年   31篇
  2020年   122篇
  2019年   142篇
  2018年   147篇
  2017年   204篇
  2016年   204篇
  2015年   141篇
  2014年   195篇
  2013年   1432篇
  2012年   232篇
  2011年   246篇
  2010年   199篇
  2009年   208篇
  2008年   231篇
  2007年   249篇
  2006年   208篇
  2005年   260篇
  2004年   271篇
  2003年   240篇
  2002年   245篇
  2001年   192篇
  2000年   157篇
  1999年   165篇
  1998年   158篇
  1997年   152篇
  1996年   135篇
  1995年   140篇
  1994年   127篇
  1993年   147篇
  1992年   119篇
  1991年   123篇
  1990年   101篇
  1989年   89篇
  1988年   97篇
  1987年   87篇
  1986年   77篇
  1985年   93篇
  1984年   89篇
  1983年   92篇
  1982年   93篇
  1981年   80篇
  1980年   75篇
  1979年   72篇
  1978年   77篇
  1977年   61篇
  1976年   69篇
  1975年   63篇
  1974年   56篇
  1973年   38篇
  1971年   33篇
排序方式: 共有8447条查询结果,搜索用时 125 毫秒
821.
In 1992, a mental‐models‐based survey in Pittsburgh, Pennsylvania, revealed that educated laypeople often conflated global climate change and stratospheric ozone depletion, and appeared relatively unaware of the role of anthropogenic carbon dioxide emissions in global warming. This study compares those survey results with 2009 data from a sample of similarly well‐educated laypeople responding to the same survey instrument. Not surprisingly, following a decade of explosive attention to climate change in politics and in the mainstream media, survey respondents in 2009 showed higher awareness and comprehension of some climate change causes. Most notably, unlike those in 1992, 2009 respondents rarely mentioned ozone depletion as a cause of global warming. They were also far more likely to correctly volunteer energy use as a major cause of climate change; many in 2009 also cited natural processes and historical climatic cycles as key causes. When asked how to address the problem of climate change, while respondents in 1992 were unable to differentiate between general “good environmental practices” and actions specific to addressing climate change, respondents in 2009 have begun to appreciate the differences. Despite this, many individuals in 2009 still had incorrect beliefs about climate change, and still did not appear to fully appreciate key facts such as that global warming is primarily due to increased concentrations of carbon dioxide in the atmosphere, and the single most important source of this carbon dioxide is the combustion of fossil fuels.  相似文献   
822.

This paper presents a critical review of the most frequently cited resurgence of ethnicity studies. Many of the sources cited in recently published ethnic relations books are found to lack an empirical base. They are essentially polemical, impressionistic and anecdotal works. Empirical studies that support the resurgence of ethnicity theme are also examined. Their shortcomings are noted. Nevertheless, these empirical studies provide convincing evidence that ethnic differences persist into the later generations. Overall, however, the empirical studies overwhelmingly document increasing assimilation. Virtually no evidence is found for the notion of a third generation resurgence.  相似文献   
823.
The concepts of the public sphere and public space have gained increasing purchase within social history. This paper contributes to this literature by theoretically developing a critical approach to both concepts. By drawing upon the insights of the Bakhtin circle, as well as Marxism and Poststructuralism, the paper suggests that public spheres under capitalism are structured through the basic contradiction between capital and labour. Each public sphere may then be seen as a refracted dialogic and spatial form of this basic contradiction, and is then best viewed as a contradictory spatial entity that obtains its unique identity through different "accents" and "word signs". The capitalist state must aim to regulate, through governance and law, dialogue within a public sphere. By focusing on the Chartist demonstration at Hyde Park, London in 1855, I show how these theories can be employed to explore how a radical social movement appropriated space by developing a working class public sphere.  相似文献   
824.
This literature review summarizes recent empirical research on the reasons disordered gamblers try, through treatment or otherwise, to resolve or reduce their gambling problems. Relevant databases and bibliographies were searched for English-language studies, published since 1998, that asked gamblers themselves about motivators for action. Found were ten studies addressing reasons for trying to resolve or reduce gambling problems, five addressing reasons for seeking help and four addressing reasons for requesting self-exclusion from casinos. Help-seeking occurred largely in response to gambling-related harms (especially financial problems, relationship issues and negative emotions) that had already happened or that were imminent. Resolution was often motivated by the same kinds of harms but evaluation/decision-making and changes in lifestyle or environment played a more prominent role. Self-exclusion was motivated by harms, evaluation/decision-making and a wish to regain control. Awareness and educational materials could incorporate messages that might encourage heavy gamblers to make changes before harms became too great. Intervention development could also benefit from more research on the motivators leading to successful (vs. failed) resolution, as well as on the ways in which disordered gamblers are able to overcome specific barriers to seeking help or reaching resolution.  相似文献   
825.
This article uses the history of debates over the US Head Start programme (1965), Early Head Start (1994) and the UK Sure Start initiative (1998), as a window on to policy transfer. In all the three, the aim was that early intervention could offer a means of boosting children’s educational attainment and of countering the wider effects of poverty on development. Nevertheless, there were also important differences between them. The first part of the article looks at UK responses to Head Start, the second at Early Head Start and the creation and subsequent direction taken by Sure Start. In the Conclusion, we sum up the arguments relating to Head Start and Sure Start and offer some broader reflections on policy transfer.  相似文献   
826.
Testing for homogeneity in finite mixture models has been investigated by many researchers. The asymptotic null distribution of the likelihood ratio test (LRT) is very complex and difficult to use in practice. We propose a modified LRT for homogeneity in finite mixture models with a general parametric kernel distribution family. The modified LRT has a χ-type of null limiting distribution and is asymptotically most powerful under local alternatives. Simulations show that it performs better than competing tests. They also reveal that the limiting distribution with some adjustment can satisfactorily approximate the quantiles of the test statistic, even for moderate sample sizes.  相似文献   
827.
828.
829.
The quadratic discriminant function is commonly used for the two group classification problem when the covariance matrices in the two populations are substantially unequal. This procedure is optimal when both populations are multivariate normal with known means and covariance matrices. This study examined the robustness of the QDF to non-normality. Sampling experiments were conducted to estimate expected actual error rates for the QDF when sampling from a variety of non-normal distributions. Results indicated that the QDF was robust to non-normality except when the distributions were highly skewed, in which case relatively large deviations from optimal were observed. In all cases studied the average probabilities of misclassification were relatively stable while the individual population error rates exhibited considerable variability.  相似文献   
830.
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