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91.
Security of infrastructure is a major concern. Traditional security schedules are unable to provide omnipresent coverage; consequently, adversaries can exploit predictable vulnerabilities to their advantage. Randomized security schedules, which randomly deploy security measures, overcome these limitations, but public perceptions of such schedules have not been examined. In this experiment, participants were asked to make a choice between attending a venue that employed a traditional (i.e., search everyone) or a random (i.e., a probability of being searched) security schedule. The absolute probability of detecting contraband was manipulated (i.e., 1/10, 1/4, 1/2) but equivalent between the two schedule types. In general, participants were indifferent to either security schedule, regardless of the probability of detection. The randomized schedule was deemed more convenient, but the traditional schedule was considered fairer and safer. There were no differences between traditional and random schedule in terms of perceived effectiveness or deterrence. Policy implications for the implementation and utilization of randomized schedules are discussed.  相似文献   
92.
We analyze a signaling game between the manager of a firm and an investor in the firm. The manager has private information about the firm's demand and cares about the short‐term stock price assigned by the investor. Previous research has shown that under continuous decision choices and the Intuitive Criterion refinement, the least‐cost separating equilibrium will result, in which a low‐quality firm chooses its optimal capacity and a high‐quality firm over‐invests in order to signal its quality to investors. We build on this research by showing the existence of pooling outcomes in which low‐quality firms over‐invest and high‐quality firms under‐invest so as to provide identical signals to investors. The pooling equilibrium is practically appealing because it yields a Pareto improvement compared to the least‐cost separating equilibrium. Distinguishing features of our analysis are that: (i) we allow the capacity decision to have either discrete or continuous support, and (ii) we allow beliefs to be refined based on either the Undefeated refinement or the Intuitive Criterion refinement. We find that the newsvendor model parameters impact the likelihood of a pooling outcome, and this impact changes in both sign and magnitude depending on which refinement is used.  相似文献   
93.
We update a previous approach to the estimation of the size of an open population when there are multiple lists at each time point. Our motivation is 35 years of longitudinal data on the detection of drug users by the Central Registry of Drug Abuse in Hong Kong. We develop a two‐stage smoothing spline approach. This gives a flexible and easily implemented alternative to the previous method which was based on kernel smoothing. The new method retains the property of reducing the variability of the individual estimates at each time point. We evaluate the new method by means of a simulation study that includes an examination of the effects of variable selection. The new method is then applied to data collected by the Central Registry of Drug Abuse. The parameter estimates obtained are compared with the well known Jolly–Seber estimates based on single capture methods.  相似文献   
94.
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   
95.
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   
96.
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   
97.
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   
98.
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   
99.
100.
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   
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