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61.
In a previous paper we considered how pharmaceutical statistics had changed between 1980 and 2000. In this paper we go on to consider some of the likely influences and changes in the world of pharmaceutical statistics over the next twenty years. Statistical research by pharmaceutical companies is supported, although its direct value in boosting company profits is challenged. The duality between fraud and conflict of interest is explored, particularly with regard to data and safety monitoring boards. Political correctness within clinical trials and (allegedly) better patient‐oriented outcomes is questioned and the whole notion of intention‐to‐treat and per‐protocol analyses is rejected in favour of pragmatic trials and explanatory trials. The dominance of SAS software within the industry is explored and the possibility for change considered. Finally, whilst the future of pharmaceutical companies is not addressed, the impact of future mergers, collaborations and take‐overs between clinical research organizations is considered. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
62.
This article examines female crime rates in twenty-seven countries over the past thirtyfive years. The results show that there has been an overall increase in total crime rates for all of the countries, and that the more economically advanced and industrialized countries have higher crime rates than the less developed nations. All countries also experienced an increase in the percent of all crimes committed by women. The percentages of violent crimes committed by women—specifically homicide and robbery—were consistently low across countries and increased only slightly over time. The percentages of property and financial crimes committed by women—specifically theft and fraud—were consistently higher than the percentages for violent crimes, and have increased more substantially over time. In addition, an analysis of the most recent data revealed a positive and significant relationship between women's overall crime rates and the countries' economic development. In those countries in which women occupy a higher status, as measured by formal years of schooling and representation in the labor force, we found some positive and significant correlations with the arrest rates for theft and fraud. There were also some strong negative relationships between female arrest rates for homicide and their status in society.  相似文献   
63.
In this paper we set out what we consider to be a set of best practices for statisticians in the reporting of pharmaceutical industry‐sponsored clinical trials. We make eight recommendations covering: author responsibilities and recognition; publication timing; conflicts of interest; freedom to act; full author access to data; trial registration and independent review. These recommendations are made in the context of the prominent role played by statisticians in the design, conduct, analysis and reporting of pharmaceutical sponsored trials and the perception of the reporting of these trials in the wider community. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
64.
A Bayesian multi-category kernel classification method is proposed. The algorithm performs the classification of the projections of the data to the principal axes of the feature space. The advantage of this approach is that the regression coefficients are identifiable and sparse, leading to large computational savings and improved classification performance. The degree of sparsity is regulated in a novel framework based on Bayesian decision theory. The Gibbs sampler is implemented to find the posterior distributions of the parameters, thus probability distributions of prediction can be obtained for new data points, which gives a more complete picture of classification. The algorithm is aimed at high dimensional data sets where the dimension of measurements exceeds the number of observations. The applications considered in this paper are microarray, image processing and near-infrared spectroscopy data.  相似文献   
65.
This paper presents the results of a survey aimed at gauging the potential acceptance of a collaborative and Web 2.0 inspired scholarly communication sector. While this sector has seen the birth of a multitude of innovative initiatives, there is still little empirical evidence of the acceptance of such initiatives by researchers. We received 349 completed questionnaires from researchers of many different disciplines. The results of the survey show that there is a strong positive attitude towards Web 2.0 and open publishing approaches. However, the major challenge still resides in combining free dissemination of results with robust and reliable quality control mechanisms.  相似文献   
66.
The conceptual predictive statistic, Cp, is a widely used criterion for model selection in linear regression. Cp serves as an estimator of a discrepancy, a measure that reflects the disparity between the generating model and a fitted candidate model. This discrepancy, based on scaled squared error loss, is asymmetric: an alternate measure is obtained by reversing the roles of the two models in the definition of the measure. We propose a variant of the Cp statistic based on estimating a symmetrized version of the discrepancy targeted by Cp. We claim that the resulting criterion provides better protection against overfitting than Cp, since the symmetric discrepancy is more sensitive towards detecting overspecification than its asymmetric counterpart. We illustrate our claim by presenting simulation results. Finally, we demonstrate the practical utility of the new criterion by discussing a modeling application based on data collected in a cardiac rehabilitation program at University of Iowa Hospitals and Clinics.  相似文献   
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Bayesian palaeoclimate reconstruction   总被引:1,自引:0,他引:1  
Summary.  We consider the problem of reconstructing prehistoric climates by using fossil data that have been extracted from lake sediment cores. Such reconstructions promise to provide one of the few ways to validate modern models of climate change. A hierarchical Bayesian modelling approach is presented and its use, inversely, is demonstrated in a relatively small but statistically challenging exercise: the reconstruction of prehistoric climate at Glendalough in Ireland from fossil pollen. This computationally intensive method extends current approaches by explicitly modelling uncertainty and reconstructing entire climate histories. The statistical issues that are raised relate to the use of compositional data (pollen) with covariates (climate) which are available at many modern sites but are missing for the fossil data. The compositional data arise as mixtures and the missing covariates have a temporal structure. Novel aspects of the analysis include a spatial process model for compositional data, local modelling of lattice data, the use, as a prior, of a random walk with long-tailed increments, a two-stage implementation of the Markov chain Monte Carlo approach and a fast approximate procedure for cross-validation in inverse problems. We present some details, contrasting its reconstructions with those which have been generated by a method in use in the palaeoclimatology literature. We suggest that the method provides a basis for resolving important challenging issues in palaeoclimate research. We draw attention to several challenging statistical issues that need to be overcome.  相似文献   
70.
Summary.  The paper investigates the life-cycle relationship of work and family life in Britain based on the British Household Panel Survey. Using hazard regression techniques we estimate a five-equation model, which includes birth events, union formation, union dissolution, employment and non-employment events. We find that transitions in and out of employment for men are relatively independent of other transitions. In contrast, there are strong links between employment of females, having children and union formation. By undertaking a detailed microsimulations analysis, we show that different levels of labour force participation by females do not necessarily lead to large changes in fertility events. Changes in union formation and fertility events, in contrast, have larger effects on employment.  相似文献   
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