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To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
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Despite extensive study concerning involuntary departures by U.S. House members, little has been said about voluntary departures from the House–-quit behavior. This paper has three primary purposes: (1) to establish a theoretical framework that models the full range of choices a representative faces in any given term, (2) to measure the impact of different variables that affect representatives' quit behavior, and (3) to explain why Republicans have been more likely to pursue higher office than their Democratic colleagues.  相似文献   
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Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables.  相似文献   
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Attitudes toward the role of women in the military require the reconciliation of two often conflicting beliefs: those toward the roles and rights of women and those toward the military. This article explores the relationships between positive attitudes toward women’s roles throughout society, or feminism, and positive attitudes toward defense spending, or militarism, both with each other and with attitudes toward gender integration in the military. Results of this analysis show there to be a negative relationship between feminism and militarism, a positive relationship between feminism and gender integration, and a negative relationship between militarism and gender integration. The results of multiple regression analysis show that feminism is the strongest predictor of attitudes toward gender integration, while militarism is weak in its predictive ability. The author argues that the issue of women in the military is more one of women’s equality than of national defense and that policy discussions should be structured accordingly. She is currently conducting research which examines how women in the United States military employ strategies to manage gender and sexuality. This research provides evidence for the claim that gender is not simply a role or an attribute, but that gender is created and recreated through our interactions with others.  相似文献   
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This paper describes the lifestyle model of gambling behavior in which compulsive gambling behavior is conceptualized as a lifestyle characterized by pseudoresponsibility, self-ascension, hypercompetitiveness, and social rule breaking/bending/ twisting. The underlying premise of this theory is that gambling behavior takes on the appearance of a lifestyle when it is viewed by the individual as a viable means of enhancing self-worth, minimizing personal insecurity, and controlling fear. Three primary areas of theoretical and research interest are covered in this paper: (1) the theoretical underpinnings of lifestyle theory; (2) the individual components (conditions, choice, cognition) of a gambling lifestyle; and (3) the developmental progression of a gambling lifestyle.The author would like to thank Henry Lesieur and anonymous reviewers of earlier versions of this paper for their helpful comments. The assertions and opinions contained herein are the private views of the author and should not be construed as official or as reflecting the views of the Federal Bureau of Prisons or United States Department of Justice.  相似文献   
69.
In this note we develop a new quantile function estimator called the tail extrapolation quantile function estimator. The estimator behaves asymptotically exactly the same as the standard linear interpolation estimator. For finite samples there is small correction towards estimating the extreme quantiles. We illustrate that by employing this new estimator we can greatly improve the coverage probabilities of the standard bootstrap percentile confidence intervals. The method does not reqiure complicated calculations and hence it should appeal to the statistical practitioner.  相似文献   
70.
The advent of thousands of Usenet groups on the Internet, covering a vast range of medical and welfare issues and ostensibly devoted to the mutual social support of participating members, has raised the potential for the development of new forms of 'virtual' health care. This article critically analyses the use by people with diabetes of one such Usenet group. It seeks to establish, first, the extent to which such a site provides some demonstrable measure of social support to its participants. This is approached by undertaking a structural analysis of the site to identify the extent of usage, and the nature of supporting interventions using a fivefold classification (instrumental, informational, esteem and social companionship and other). Second, the article attempts to identify any disparity between the lay health-knowledge in evidence and biomedical opinions proffered by the use of a panel of consultant diabetiologists. The results of the analysis suggest that the diabetes newsgroup provides an example of an active forum for largely well-informed participants who routinely use the media as an aid to the reflexive management of their medical condition. It also raises the prospect of a renegotiated relationship between medical knowledge and lay experience based upon shared learning  相似文献   
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