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981.
It has long been asserted that in univariate location-scale models, when concerned with inference for either the location or scale parameter, the use of the inverse of the scale parameter as a Bayesian prior yields posterior credible sets that have exactly the correct frequentist confidence set interpretation. This claim dates to at least Peers, and has subsequently been noted by various authors, with varying degrees of justification. We present a simple, direct demonstration of the exact matching property of the posterior credible sets derived under use of this prior in the univariate location-scale model. This is done by establishing an equivalence between the conditional frequentist and posterior densities of the pivotal quantities on which conditional frequentist inferences are based.  相似文献   
982.
In this paper, we establish the role of concomitants of order statistics in the unique identification of the parent bivariate distribution. From the results developed, we have illustrated by examples the process of determination of the parent bivariate distribution using a marginal pdf and the pdf of either of the concomitant of largest or smallest order statistic on the other variable. An application of the results derived in modeling of a bivariate distribution for data sets drawn from a population as well is discussed.  相似文献   
983.
984.
Mixture distributions have become a very flexible and common class of distributions, used in many different applications, but hardly any literature can be found on tests for assessing their goodness of fit. We propose two types of smooth tests of goodness of fit for mixture distributions. The first test is a genuine smooth test, and the second test makes explicit use of the mixture structure. In a simulation study the tests are compared to some traditional goodness of fit tests that, however, are not customised for mixture distributions. The first smooth test has overall good power and generally outperforms the other tests. The second smooth test is particularly suitable for assessing the fit of each component distribution separately. The tests are applicable to both continuous and discrete distributions and they are illustrated on three medical data sets.  相似文献   
985.
This secondary data analysis examined racial disparities in associations betwen welfare dependence/financial independence and human capital, local economy, and state TANF policies. A sample of 6,737 parents was extracted from the public-use data set titled “National Longitudinal Survey of Youth.” Results showed that restrictive TANF policies reduced African Americans’ likelihood of welfare use and increased likelihood of their financial independence. Multinomial logistic results also showed that, among Hispanics, employment growth in neighboring counties promoted welfare use; whereas among Caucasians such growth promoted financial independence. County poverty increased (a) Caucasians’ likelihood of welfare use and (b) Hispanics’ likelihood of being working poor; it decreased Caucasians’ and African Americans’ likelihood of financial independence. Across ethnic groups, education reduced likelihood of welfare use and working poor status; across minority groups, education increased likelihood of financial independence, but among Caucasians it decreased such likelihood. Across ethnic groups, occupational skills hindered dependence and improved odds of employment (regardless of welfare or poverty status). This study concluded the studied TANF policies and job markets were not color-blind. Interventions this study implies include less-restrictive TANF policies, generous support services, TANF staff cultural-competence training, and antidiscrimination rules. Research investigating particular TANF policies’ and services’ effects by ethnicity might prove useful.  相似文献   
986.
987.
What we know about the experiences of black teachers is limited, especially considering the vast amount of research conducted on and about black boys and young men. This article describes and analyzes how a black teacher at a suburban high school in the Midwestern United States negotiated professional relationships through culturally relevant discourse. Anthony Bell was the only black male teacher participating in a classroom discourse analysis study group at a diverse suburban high school. Throughout the course of the semester, Anthony’s stated objective for learning discourse analysis was to understand, structure, and facilitate more productive conversations with a struggling student teacher he was mentoring. Yet Anthony also used his discursive inquiry to “trouble the water” in his classroom and in the study group workshops. Participation in the study group provided Anthony with metalinguistic tools to critique his interactions with his students, student teacher, and professional peers. Anthony’s analyses of his own teaching, his student teacher’s work, the study group, and the school index themes in critical and critical race theory in education. As he became a teacher researcher, Anthony reported a greater sense of professional self-efficacy, eventually facilitating a successful workshop at a national teacher conference. Anthony’s case is an exemplar of the unique and critical role of black men who teach, as well as the imperative of practitioner research within the current climate in teacher education.  相似文献   
988.
Many immigrants in Western countries hail from countries where attitudes towards gender relations and sexual norms are considerably more conservative than in the host countries where they eventually settle. This paper assesses whether immigrants and their children acculturate in this dimension, and how migrants’ cultural practices and economic integration influence this process. Presenting a conceptual and methodological innovation, this paper treats acculturation as a process by which immigrants (and their children) shift from the attitude distribution in the origin country to the one of the host country. Using a cross-classified hierarchical regression model and data on attitudes towards homosexuality in 83 countries of origin and 23 destination countries, I model the relative influence of origin and destination contexts on the attitudes of 15,000 immigrants and children of immigrants in Europe. In line with previous work, I find considerable evidence for acculturation across and within generations, but also important variation: respondents who use the home-country language, who are religious, or who are economically marginalised, show less acculturation in attitudes, though these effects vary between immigrants and the second generation.  相似文献   
989.
Over the past decades, robots have been heavily used for flow lines to increase productivity and product quality and to relieve workers of repetitive and dangerous tasks. However, despite continuous improvement of robots, the occurrence of failures remains a significant challenge in the operation of automated flow lines. Due to the connection of the stations in a flow line via a material handling system, failures at one station can quickly lead to throughput losses due to blocking and starving of upstream and downstream stations, respectively. To some extent, these throughput losses can be reduced by installing buffers between the stations. However, the installation of buffers requires considerable investments and scarce factory space. Therefore, the minimization of the total number of buffers is one of the primary objectives in flow line planning. Due to the advances of manufacturing technologies that form the foundation of “Industry 4.0”, new solutions to reduce throughput losses caused by equipment failures open up. One solution is a redundant configuration, in which downstream stations automatically take over the operations of failed stations in the event of failure. The throughput loss in these situations mainly depends on the level of redundancy designed into the system. Based on existing methods for the design of automated flow lines, we present two line balancing formulations for the configuration of automated flow lines under consideration of redundancies. The first formulation aims at maximizing the lines’ level of redundancy. The second formulation aims at a balanced allocation of redundancies along the line. To evaluate the presented formulations, we compare the performance with an existing line balancing approach for automated lines. With respect to this approach, improvements of the throughput rate between 3 % and 7 % are achieved.  相似文献   
990.
We seek to explain the development of the educational gap between children in “out‐of‐home care” (CLA), children deemed in social need (CIN), and other pupils. A cohort of 642,805 pupils aged 16 in 2013 was used to chart the educational progress of the full cohort, the CLA (n = 6,236), the CIN in 2012 or 2013 but not CLA (n = 20,384), and a sample individually matched with the CLA (n = 11,084). At age 7, attainment of the CLA and CIN was approximately 1 standard deviation lower than the cohort average and predicted attainment at 16. At this point, the persistent “CIN” (those with earlier and persistent needs) had the lowest attainment relative to others, and this declined further during secondary school. Those entering care before or during primary school had very low attainment at age 7, but their relative attainment did not decline. Attainment of CLA and CIN at age 16 likely reflects early environment, special educational needs, and poor relationships with secondary school. Policy, research, and intervention should focus on CIN as well as CLA, do so before entry to care, and take account of the onset of, and probable reasons for, educational difficulties.  相似文献   
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