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   3380篇
  免费   100篇
  国内免费   1篇
管理学   505篇
民族学   16篇
人才学   1篇
人口学   276篇
丛书文集   26篇
理论方法论   358篇
综合类   27篇
社会学   1850篇
统计学   422篇
  2023年   22篇
  2022年   13篇
  2021年   15篇
  2020年   47篇
  2019年   67篇
  2018年   81篇
  2017年   95篇
  2016年   89篇
  2015年   61篇
  2014年   77篇
  2013年   580篇
  2012年   101篇
  2011年   95篇
  2010年   81篇
  2009年   89篇
  2008年   104篇
  2007年   106篇
  2006年   103篇
  2005年   107篇
  2004年   104篇
  2003年   110篇
  2002年   112篇
  2001年   67篇
  2000年   56篇
  1999年   66篇
  1998年   53篇
  1997年   67篇
  1996年   70篇
  1995年   44篇
  1994年   51篇
  1993年   49篇
  1992年   47篇
  1991年   50篇
  1990年   47篇
  1989年   37篇
  1988年   33篇
  1987年   35篇
  1986年   21篇
  1985年   27篇
  1984年   44篇
  1983年   42篇
  1982年   35篇
  1981年   47篇
  1980年   32篇
  1979年   24篇
  1978年   26篇
  1977年   31篇
  1976年   30篇
  1975年   17篇
  1973年   21篇
排序方式: 共有3481条查询结果,搜索用时 31 毫秒
101.
The estimation of abundance from presence–absence data is an intriguing problem in applied statistics. The classical Poisson model makes strong independence and homogeneity assumptions and in practice generally underestimates the true abundance. A controversial ad hoc method based on negative‐binomial counts (Am. Nat.) has been empirically successful but lacks theoretical justification. We first present an alternative estimator of abundance based on a paired negative binomial model that is consistent and asymptotically normally distributed. A quadruple negative binomial extension is also developed, which yields the previous ad hoc approach and resolves the controversy in the literature. We examine the performance of the estimators in a simulation study and estimate the abundance of 44 tree species in a permanent forest plot.  相似文献   
102.
Remote sensing of the earth with satellites yields datasets that can be massive in size, nonstationary in space, and non‐Gaussian in distribution. To overcome computational challenges, we use the reduced‐rank spatial random effects (SRE) model in a statistical analysis of cloud‐mask data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on board NASA's Terra satellite. Parameterisations of cloud processes are the biggest source of uncertainty and sensitivity in different climate models’ future projections of Earth's climate. An accurate quantification of the spatial distribution of clouds, as well as a rigorously estimated pixel‐scale clear‐sky‐probability process, is needed to establish reliable estimates of cloud‐distributional changes and trends caused by climate change. Here we give a hierarchical spatial‐statistical modelling approach for a very large spatial dataset of 2.75 million pixels, corresponding to a granule of MODIS cloud‐mask data, and we use spatial change‐of‐Support relationships to estimate cloud fraction at coarser resolutions. Our model is non‐Gaussian; it postulates a hidden process for the clear‐sky probability that makes use of the SRE model, EM‐estimation, and optimal (empirical Bayes) spatial prediction of the clear‐sky‐probability process. Measures of prediction uncertainty are also given.  相似文献   
103.
We qualitatively explored reasons why transgendered women may engage in sexual risk that could lead to HIV infection. Specifically, we conducted this investigation with transgendered women identifying as Black/African American. Interviews from 17 participants were audio taped and analyzed. Four themes emerged. Women commonly reported they had a strong need/desire to be loved by men. Many stated they had and would engage in unprotected sex to obtain and preserve such a relationship. Nearly all were currently using female hormones. Nine obtained their hormones through non-medical means including the Internet, transgendered friends, and street vendors. For these women hormone injections often involved sharing needles/syringes. Selling sex was a common practice and many women did so without the benefit of condom use. Finally, women experienced multiple forms of societal discrimination. By being caught between worlds (straight, gay, male, and female) transgendered women may be placed into situations where avoiding HIV risk is extremely difficult.  相似文献   
104.
Every state requires a home study before the placement of foster children for adoption. This article examines the history of home studies, presents results from expert interviews on the changing processes and purposes of home studies, and explores current challenges for the field. The article also introduces the Structured Analysis Family Evaluation (SAFE), a uniform home study format that encourages consistent family evaluations across workers, agencies, and jurisdictions. The article clarifies how SAFE may address challenges facing foster care and adoption practice.  相似文献   
105.
Internet gambling is growing rapidly, as is concern about its possible effect on the public’s health. This paper reports the results of the first prospective longitudinal study of actual Internet sports gambling behavior during eight study months. Data include recorded fixed-odds bets on the outcome of sporting contests and live-action bets on the outcome of events within contests for 40,499 Internet sports gambling service subscribers who enrolled during February 2005. We tracked the following primary gambling behaviors: daily totals of the number of bets made, money bet, and money won. We transformed these variables into measures of gambling involvement. We analyzed behavior for both fixed-odds and live-action bets. The median betting behavior of the 39,719 fixed-odds bettors was to place 2.5 bets of €4 (approximately $5.3 US) every fourth day during the median 4 months from first to last bet. This typical pattern incurred a loss of 29% of the amount wagered. The median betting behavior of the 24,794 live-action bettors was to place 2.8 wagers of €4 every fourth day during the median duration of 6 weeks at a loss of 18% of the amount wagered. We also examined the behavior of empirically determined groups of heavily involved bettors whose activity exceeded that of 99% of the sample.  相似文献   
106.
A new version of the age-old controversy between religion and science has been launched by today’s intelligent design movement. Although ostensibly concerned simply with combating Darwinism, this new creationism seeks to drive a “wedge” into the materialist view of the world, originating with the ancient Greek philosopher Epicurus and manifested in modern times by Darwin, Marx, and Freud. Intelligent design proponents thus can be seen as challenging not only natural and physical science but social science as well. In this article, we attempt to explain the long history of this controversy, stretching over millennia, and to defend science (especially social science) against the criticisms of intelligent design proponents – by defending science’s materialist roots.
Brett Clark (Corresponding author)Email:
John Bellamy FosterEmail:
Richard YorkEmail:

Brett Clark   received his Ph.D. from the University of Oregon and is the Editorial Director of Monthly Review Press. His research interests are ecology, political economy, and science. He has published articles and review essays in Theory and Society, The Sociological Quarterly, Organization & Environment, and Critical Sociology. He received the 2007 Outstanding Publication Award from the Environment and Technology Section of the American Sociological Association for a series of articles (one of which was the article “Carbon Metabolism: Global Capitalism, Climate Change, and the Biospheric Rift,” published in Theory and Society in 2005) with Richard York. John Bellamy Foster   is Professor of Sociology at the University of Oregon and editor of Monthly Review (New York). He is the author of The Theory of Monopoly Capitalism (1986); The Vulnerable Planet (1994); “Marx’s Theory of Metabolic Rift,” American Journal of Sociology (1999); Marx’s Ecology (2000); Ecology Against Capitalism (2002); Naked Imperialism (2006); and (with Paul Burkett) “Metabolism, Energy, and Entropy in Marx’s Critique of Political Economy,” Theory and Society (2006). Richard York   is Associate Professor of Sociology at the University of Oregon and co-editor of the Sage journal Organization & Environment. His research focuses on human interaction with the natural environment and the philosophy, history, and sociology of science. He has published articles in American Sociological Review, Gender & Society, Rural Sociology, Social Problems, Social Science Research, Sociological Forum, The Sociological Quarterly, Theory and Society, and other scholarly journals. He has twice (2004 and 2007) received the Outstanding Publication Award from the Environment and Technology Section of the American Sociological Association.  相似文献   
107.
The Collegiate Learning Assessment: facts and fantasies   总被引:4,自引:0,他引:4  
The Collegiate Learning Assessment (CLA) is a computer administered, open-ended (as opposed to multiple-choice) test of analytic reasoning, critical thinking, problem solving, and written communication skills. Because the CLA has been endorsed by several national higher education commissions, it has come under intense scrutiny by faculty members, college administrators, testing experts, legislators, and others. This article describes the CLA's measures and what they do and do not assess, how dependably they measure what they claim to measure, and how CLA scores differ from those on other direct and indirect measures of college student learning. For instance, analyses are conducted at the school rather than the student level and results are adjusted for input to assess whether the progress students are making at their school is better or worse than what would be expected given the progress of "similarly situated" students (in terms of incoming ability) at other colleges.  相似文献   
108.
This paper presents a personal perspective on the history, current research, and emerging topics in the field of Service Operations Management. I see research in the field evolving from a focus on classifications and operations research models in the 1970s and 1980s, to a current focus on laboratory studies, and survey- and case-based research. Selected current research is presented under the following headings: Service encounter design, service quality, drivers of service competitiveness, yield management, and the information revolution and the globalization of services. Examples of creativity in service delivery and some whimsical characteristics of service junkies are also presented.  相似文献   
109.
110.
In this study the potential performance benefits of easy goals were examined within the multiple cue probability learning paradigm (MCPLP). Specifically, the effects of varying levels of goal difficulty on performance and risk propensity (used to define a form of commitment) were investigated. With few exceptions, previous studies demonstrated support for difficult goals. In this study, contrary to the majority of past evidence, as goals became easier decision quality significantly improved. Moreover, risk propensity increased with easier goals and, as suggested by a post-hoc analysis, had more direct impact on decision makers’ behaviors than goal levels. Goal-related behavior in complex MCPLP tasks appears to significantly differ from the majority of goal evidence in other types of research due to the tendency for subjects to view complex task properties in the same context as goal levels.  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