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11.
    
Motivated by our meta‐analytic dataset involving survival rates after treatment for critical leg ischemia, we develop and apply a new multivariate model for the meta‐analysis of study level survival data at multiple times. Our data set involves 50 studies that provide mortality rates at up to seven time points, which we model simultaneously, and we compare the results to those obtained from standard methodologies. Our method uses exact binomial within‐study distributions and enforces the constraints that both the study specific and the overall mortality rates must not decrease over time. We directly model the probabilities of mortality at each time point, which are the quantities of primary clinical interest. We also present I2 statistics that quantify the impact of the between‐study heterogeneity, which is very considerable in our data set. © 2014 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.  相似文献   
12.
    
Distributed data networks representing large diverse populations are an expanding focus of drug safety research. However, interpreting results is difficult when treatment effect estimates vary across datasets (i.e., heterogeneity). In a previous study, risk estimates were generated for selected drugs and potential adverse outcomes. Analyses were replicated across eight distributed data sources using an identical analytic structure. To evaluate heterogeneity of risk estimates across data sources, the estimates were combined with summary‐level data characterizing the population of each data source. Meta‐analysis, meta‐regression, and plots of the influence on overall results versus contribution to heterogeneity were examined and used to illustrate an approach to heterogeneity assessment. Heterogeneity, as measured by the I‐squared statistic, was high with variability across outcomes. Plots of the relationship between influence on overall results and contribution to heterogeneity suggest that certain datasets and characteristics were influential but there was variability dependent on the drug and outcome being assessed. Exploratory meta‐regression identified many possible influential factors, but may be subject to ecological bias and false positive conclusions. Distributed data network drug safety analyses can produce heterogeneous risk estimates that may not be easily explained. Approaches illustrated here can be useful for research that is subject to similar problems with heterogeneity. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
13.
    
In a model of a competitive industry selling base goods and add‐ons, we investigate the conditions under which citizen‐consumers will support policies that eliminate behavioral inefficiencies induced by naïve consumers. Unregulated competitive markets have two effects: they produce deadweight losses, and they redistribute income away from biased consumers. Both unbiased and naïve consumers believe that they benefit from this redistribution (the naïve consumers are wrong), so support for efficiency‐improving regulation is limited. Extending our model to consumers with partial sophistication about their naïveté, we predict patterns of regulation consistent with the form and timing of the Credit Card Accountability Responsibility and Disclosure (CARD) Act of 2009.  相似文献   
14.
    
Spatio-temporal surveillance methods for detecting outbreaks of disease are fairly common in the literature with the scan statistic setting the benchmark. If the shape and size of the outbreaks are known in advance, then the scan approach can be designed to efficiently detect these, however, this is seldom true. Therefore we want to devise plans that are efficient at detecting a number of outbreaks that vary in size and shape. This paper examines plans which use the exponential weighted moving average statistic to build temporal memory into plans and tries to develop robust plans for detecting outbreaks of unknown shapes and sizes.  相似文献   
15.
    
This article assesses the quality and apparent use of regulatory analysis for economically significant regulations proposed by federal agencies in 2008. A nine-member research team used a six-point (0-5) scale to evaluate regulatory analyses according to criteria drawn from Executive Order 12866 and Office of Management and Budget Circular A-4. Principal findings include: (1) the average quality of regulatory analysis, though not high, is somewhat better than previous regulatory scorecards have shown; (2) quality varies widely; (3) biggest strengths are accessibility and clarity; (4) biggest weaknesses are analysis of the systemic problem and retrospective analysis; (5) budget or \"transfer\" regulations usually receive low-quality analysis; (6) a minority of the regulations contain evidence that the agency used the analysis in significant decisions; (7) quality of analysis is positively correlated with the apparent use of the analysis in regulatory decisions; and (8) greater diffusion of best practices could significantly improve the overall quality of regulatory analysis.  相似文献   
16.
    
Many argue that elements of a society's norms, culture, or social capital are central to understanding its development. However, these notions have been difficult to capture in economic models. Here we explore a possible role for “trustworthiness” as corresponding to social capital. Individuals are trustworthy when they perform in accordance with promises, even if this does not maximise their payoffs. The usual focus on incentive structures in motivating behaviour plays no role here. Instead, we emphasise more deep‐seated modes of behaviour and consider trustworthy agents being socialised to act as they do. To model this socialisation, we borrow from a process of preference evolution pioneered by Bisin and Verdier (2001). The model developed endogenously accounts for social capital and explores its role in the process of economic development. It captures in a simple, formal way the interaction between social capital and the economy's productive processes. The results obtained caution against rapid reform and provide an explanation for why late‐developing countries may not easily be able to transplant the modes of production that have proved useful in the West. (JEL: O1, O3, O4, Z1)  相似文献   
17.
Doctors involved in child abuse proceedings may be subjected to much blame and pressure because of their role as ‘messenger’. They frequently need assistance with complaints procedures, disciplinary proceedings, public inquiries, litigation, media problems and other threats to their professional integrity and reputation. The medical model of support which may be offered by the defence organizations has much to commend it to other workers in the field. The author is a medico-legal adviser at the Medical Defence Union, and was extensively involved in assisting doctors at the Cleveland and Orkney Inquiries. From this privileged position he surveys the various procedures which may be used by parents and others to challenge paediatricians, and sets out possible ways in which practical support may be given.  相似文献   
18.
Sexual assault is underreported in the United States. Survivors are often reluctant to make police reports for various reasons; one is fear of revictimization by criminal justice professionals. Conversely, police officers often lack skills for interviewing crime victims. Posttraumatic stress reactions among victims can exacerbate the problem. Although some victims prefer female interviewers, it is not known whether they are more skilled. A sample of 429 police officers completed a written survey testing their rape myth acceptance and knowledge of how to interview rape reporters. A significant relationship between rape myth acceptance and interviewing skill was discovered. Although officer gender was related to interviewing skill, the effect was mediated by rape myth acceptance. Specific officer behaviors related to high rape myth acceptance were identified. Implications for selection of police to conduct victim interviews were discussed.  相似文献   
19.
We investigate organizational determinants and performance effects of formal target agreements for employees based on the IAB establishment panel, a representative panel of German establishments. The results show that establishments with a high employee turnover rate, a large proportion of temporary workers, and a highly qualified workforce are significantly more likely to implement target agreements. Also, establishments with works councils installed are more likely to do so, controlling, among others, for firm size. Concerning organizational performance, we apply a first-difference and a fixed effects approach and find that establishments that implement target agreements achieve around 5 % higher total sales compared to firms that did not introduce this practice. Hence, organizations seem to benefit from the implementation of formal target agreements for employees.  相似文献   
20.
We construct a quantitative equilibrium model with firms setting prices in a staggered fashion and use it to ask whether monetary shocks can generate business cycle fluctuations. These fluctuations include persistent movements in output along with the other defining features of business cycles, like volatile investment and smooth consumption. We assume that prices are exogenously sticky for a short time. Persistent output fluctuations require endogenous price stickiness in the sense that firms choose not to change prices much when they can do so. We find that for a wide range of parameter values, the amount of endogenous stickiness is small. Thus, we find that in a standard quantitative model, staggered price‐setting, alone, does not generate business cycle fluctuations.  相似文献   
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