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101.
Based on semi-structured interviews answered by professionals in Architecture and Interior Design areas, this research aimed to investigate, how these professionals develop their projects. Considering a real situation, the research tried to find out how these professionals consider users necessities and opinions. It was also verified which attributes are considered most relevant and how these professionals correlate them to uses demands about ergonomic aspects and intrinsic characteristics of each project. The paper is concluded presenting a list of attributes that were identified as the most important when developing a design for a home kitchen (as example), and some considerations about this topic are also presented.  相似文献   
102.
Summary.  Posterior distributions for the joint projections of future temperature and precipitation trends and changes are derived by applying a Bayesian hierachical model to a rich data set of simulated climate from general circulation models. The simulations that are analysed here constitute the future projections on which the Intergovernmental Panel on Climate Change based its recent summary report on the future of our planet's climate, albeit without any sophisticated statistical handling of the data. Here we quantify the uncertainty that is represented by the variable results of the various models and their limited ability to represent the observed climate both at global and at regional scales. We do so in a Bayesian framework, by estimating posterior distributions of the climate change signals in terms of trends or differences between future and current periods, and we fully characterize the uncertain nature of a suite of other parameters, like biases, correlation terms and model-specific precisions. Besides presenting our results in terms of posterior distributions of the climate signals, we offer as an alternative representation of the uncertainties in climate change projections the use of the posterior predictive distribution of a new model's projections. The results from our analysis can find straightforward applications in impact studies, which necessitate not only best guesses but also a full representation of the uncertainty in climate change projections. For water resource and crop models, for example, it is vital to use joint projections of temperature and precipitation to represent the characteristics of future climate best, and our statistical analysis delivers just that.  相似文献   
103.
A significant decline in biodiversity is associated with the current and upcoming degree of urbanization. A challenging strategy to address this conflict is to make urban growth compatible with biodiversity protection and in this context urban parks can play a crucial role. Urban systems are highly dynamic and complex human-shaped ecosystems, where the relationship between species and environment may be altered and make the preservation of biodiversity within them a challenging goal. In this study, we analysed how different environmental features affect bird biodiversity in one of the most urbanized areas of Italy (the metropolitan area of Milan) at different spatial scales. Bird surveys were conducted in fifteen urban and peri-urban parks and environmental variables at landscape and local scale recorded. Results showed that a mixture of land covers and the presence of water bodies inside urban parks favoured species occurrence and abundance at landscape scale, but a surrounding dense urban matrix deflated biodiversity. At local scale, woodland cover and presence of water bodies were key determinants in ensuring overall high biodiversity but local-specific vegetation management produced an unusual pattern for forests species. In particular, the maintenance of large trees may not result in biodiversity support for forest bird species if large trees are not located in woodland areas with a significant tree density. To understand biodiversity patterns and provide useful information for urban planning and design, we need to provide insights into species/environment relationships at multiple scales in the urban environment.  相似文献   
104.
Fertility, or childbearing, expectations have been increasingly identified as an important area of research, at least in part because expectations may help us to understand family issues of concern across the globe such as unintended pregnancies, low fertility, and delayed childbearing. While much research has focused on the link between expectations and behavior, this study extends the literature by asking how those expectations were shaped initially. Specifically, we explore how one’s economic context is related to expectations. This paper further extends the literature by focusing on two dimensions of the parenthood expectations of young people (men and women aged 18–27). Using the 2005, 2007, 2009, and 2011 waves of the Panel Studies of Income Dynamics (PSID) Transition to Adulthood (TA) sample, we considered whether young people expected to have children in the future and, for those who did, when they expected to do so. The results support financial-strain theories of the relationship between (subjective and objective) economic circumstances and childbearing expectations. Women and men with lower earnings, less education, and more worries about their future job prospects are more uncertain whether they will have children. Of those who expect to have children, those with more education and more worries expect to do so later in life. Further analyses reveal that race and gender condition these relationships.  相似文献   
105.
106.
Vine copulas are a highly flexible class of dependence models, which are based on the decomposition of the density into bivariate building blocks. For applications one usually makes the simplifying assumption that copulas of conditional distributions are independent of the variables on which they are conditioned. However this assumption has been criticised for being too restrictive. We examine both simplified and non‐simplified vine copulas in three dimensions and investigate conceptual differences. We show and compare contour surfaces of three‐dimensional vine copula models, which prove to be much more informative than the contour lines of the bivariate marginals. Our investigation shows that non‐simplified vine copulas can exhibit arbitrarily irregular shapes, whereas simplified vine copulas appear to be smooth extrapolations of their bivariate margins to three dimensions. In addition to a variety of constructed examples, we also investigate a three‐dimensional subset of the well‐known uranium data set and visually detect the fact that a non‐simplified vine copula is necessary to capture its complex dependence structure.  相似文献   
107.
Health policy is increasingly confronted with the demand for financing genetic testing on inherited susceptibility to disease. Tests on polymorphism/SNP associated with multicausal and chronic conditions are already offered in private commercial institutions or in academic hospitals. The increasing pressure on public health services to offer SNP testing leads to first methodological approaches for a generally valid regulatory framework applicable for inclusion or refusal of genetic tests into the public health services. Systematic search in Medline, Embase and the Web for methodological papers or guidelines for the assessment of polymorphism-screening. Since genetic testing has not only clinical and economic effects on health care, but also primarily ethical consequences by profiling our understanding of “health” and “disease”, this paper gives an overview of relevant aspects and background information to consider in the assessment of genetic tests. Although 2–3 million SNPs are identified and the journals are full of reported “significant” associations between disease and mutation, only a few can be replicated unequivocally. The ACCE (Analytic and Clinical Validity, Clinical utility; Ethical, legal and social implications)-framework was developed by the Center of Disease Control for the assessment of genetic testing. This standardised appraisal approach proposes collecting and evaluating: (a) Prevalence, genotype-/phenotype-relation. (b) Clinical presentation: natural history; the different expressions of disease. (c) Performance of the genetic test. (d) Implications for therapy and prevention. (e) Conclusion for clinical applications of risk-profiling of health on their susceptibility to disease and/or for clarification of disease for therapy planning. Since genetic testing is urging its way into the health care system, the actual danger is, that population screening starts before valid evidence from big prospective studies have been carried out and delivered proofs of direct causal associations. Before diffusing into the health care system we are suggesting to take a cautious and standardised approach.  相似文献   
108.
In this article, we scrutinize the often stated assumption that labor migrants in Germany turn away from integration and reaffirm their ethnicity by examining their identificational, cognitive, and social assimilation processes. Using data from the German Socio‐economic Panel, we present trend analyses of different hostland‐ and homeland‐related indicators for the past fifteen years. Results are presented separately for first‐ and second‐generation migrants from Turkey, the EU, and the former Yugoslavia. While not all assimilation‐related indicators change a great deal over time, they show at least a substantial difference between the first and the second generation. With regard to the homeland‐related indicators, the results by no means suggest that Turkish migrants try to compensate for their comparatively disadvantaged social status by revitalizing ethnic cultural habits or homeland‐oriented identifications.  相似文献   
109.
We address the identifiability and estimation of recursive max‐linear structural equation models represented by an edge‐weighted directed acyclic graph (DAG). Such models are generally unidentifiable and we identify the whole class of DAG s and edge weights corresponding to a given observational distribution. For estimation, standard likelihood theory cannot be applied because the corresponding families of distributions are not dominated. Given the underlying DAG, we present an estimator for the class of edge weights and show that it can be considered a generalized maximum likelihood estimator. In addition, we develop a simple method for identifying the structure of the DAG. With probability tending to one at an exponential rate with the number of observations, this method correctly identifies the class of DAGs and, similarly, exactly identifies the possible edge weights.  相似文献   
110.
In recent years analyses of dependence structures using copulas have become more popular than the standard correlation analysis. Starting from Aas et al. ( 2009 ) regular vine pair‐copula constructions (PCCs) are considered the most flexible class of multivariate copulas. PCCs are involved objects but (conditional) independence present in data can simplify and reduce them significantly. In this paper the authors detect (conditional) independence in a particular vine PCC model based on bivariate t copulas by deriving and implementing a reversible jump Markov chain Monte Carlo algorithm. However, the methodology is general and can be extended to any regular vine PCC and to all known bivariate copula families. The proposed approach considers model selection and estimation problems for PCCs simultaneously. The effectiveness of the developed algorithm is shown in simulations and its usefulness is illustrated in two real data applications. The Canadian Journal of Statistics 39: 239–258; 2011 © 2011 Statistical Society of Canada  相似文献   
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