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161.
We analyse theoretical properties of the slice sampler. We find that the algorithm has extremely robust geometric ergodicity properties. For the case of just one auxiliary variable, we demonstrate that the algorithm is stochastically monotone, and we deduce analytic bounds on the total variation distance from stationarity of the method by using Foster–Lyapunov drift condition methodology.  相似文献   
162.
Among the Maori of New Zealand, Aboriginals of Australia, and other Indigenous peoples, family dynamics strongly influence the ways that issues emerge in counseling. This study explores aspects of gender and power within the context of birth practices in rural Nepal. In‐depth interviews were conducted with 15 postpartum women, as well as family members, to collect narratives of birthing experiences that highlight issues of oppression, marginalisation, and power struggles. Implications for multicultural and social justice awareness in family therapy are discussed, especially with regard to the subtle, disguised ways that power operates behind the scenes, often sabotaging efforts by health and mental health professionals to bemost helpful.  相似文献   
163.
Urbanization is increasing in arid and semi-arid regions of the world and impacting native ecosystems through disturbance, climatic modification, and pollution deposition. Arid ecosystems often exhibit a mosaic of shrub/tree canopy covered and non-canopy covered patches that differ in elemental pools and processes. We measured belowground ecosystem attributes and processes in native Larrea tridentata {(D.C.) Cov} dominated communities along an urban–rural gradient in Phoenix, Arizona. Organic carbon (C), total nitrogen (N), and nitrate levels were significantly greater in the urban locations, but soil respiration rates (Rs) were higher at the rural sites. Urban sites exhibited no difference in Rs and N between the canopy and interplant patches while both the rural and suburban sites had significantly greater N and higher Rs under the canopy than in the interplant spaces. Soil respiration rates at the urban locations were not correlated with either soil moisture or temperature individually. These data suggest that urbanization has caused a disconnect of ecological pattern and processes in L. tridentata ecosystems within the urban setting such that water and N limitations no longer explain expected spatial Rs patterns, or elemental pools.  相似文献   
164.
This paper examines the use of costs and cost functions to model lot‐sizing decisions in batch manufacturing. The cost functions used to model a wide variety of manufacturing systems are typically derived from average cost models of unconstrained inventory problems. The use of setups and average inventories as the basis for modeling the economics of a typical batch manufacturing cell is shown to be inadequate. An alternative physical model that focuses on lead times provides a model that more closely represents the underlying value of such a cell.  相似文献   
165.
We devise methods to estimate probability density functions of several populations using observations with uncertain population membership, meaning from which population an observation comes is unknown. The probability of an observation being sampled from any given population can be calculated. We develop general estimation procedures and bandwidth selection methods for our setting. We establish large-sample properties and study finite-sample performance using simulation studies. We illustrate our methods with data from a nutrition study.  相似文献   
166.
At present, there are situations in antibiotic drug development where the low number of enrollable patients with key problem pathogens makes it impossible to conduct fully powered non‐inferiority trials in the traditional way. Recent regulatory changes have begun to address this situation. In parallel, statistical issues regarding the application of alternative techniques, balancing the unmet need with the level of certainty in the approval process, and the use of additional sources of data are critical areas to increase development feasibility. Although such approaches increase uncertainty compared with a traditional development program, this will be necessary to allow new agents to be made available. Identification of these risks and explicit discussion around requirements in these areas should help clarify the situation, and hence, the feasibility of developing drugs to treat the most concerning pathogens before the unmet need becomes even more acute than at present. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
167.
168.
为了处理序列曲线间的负相关等问题,并使关联满足一定的性质,基于灰色关联分析的基本思想,本文利用数列曲线的平均相对变化态势构建了一种新的灰色绝对关联度模型,并探讨了模型的唯一性、对称性、相似性、平行性、一致性等性质,而后以新模型对我国及各省市区产业结构的有序度进行了测算,结果表明新模型计算简单,计算量小,更与实际相符。  相似文献   
169.
Etzioni’s article is thought provoking, and contains a series of arguments that would be useful lines of inquiry for scholars of public opinion. In many ways, these ideas link to, and can enrich existing areas of research on opinion formation, opinion change, and political behavior more broadly. Specifically, the elite vs. mass nature of these dialogs, the extent to which they are actual political discussions, and the impact of polarization on them are avenues where these ideas can inform broader understandings of public opinion, and vice versa. Etzioni’s arguments about the role of morals in political discussion and as agents of opinion change warrant further inquiry.  相似文献   
170.
We often rely on the likelihood to obtain estimates of regression parameters but it is not readily available for generalized linear mixed models (GLMMs). Inferences for the regression coefficients and the covariance parameters are key in these models. We presented alternative approaches for analyzing binary data from a hierarchical structure that do not rely on any distributional assumptions: a generalized quasi-likelihood (GQL) approach and a generalized method of moments (GMM) approach. These are alternative approaches to the typical maximum-likelihood approximation approach in Statistical Analysis System (SAS) such as Laplace approximation (LAP). We examined and compared the performance of GQL and GMM approaches with multiple random effects to the LAP approach as used in PROC GLIMMIX, SAS. The GQL approach tends to produce unbiased estimates, whereas the LAP approach can lead to highly biased estimates for certain scenarios. The GQL approach produces more accurate estimates on both the regression coefficients and the covariance parameters with smaller standard errors as compared to the GMM approach. We found that both GQL and GMM approaches are less likely to result in non-convergence as opposed to the LAP approach. A simulation study was conducted and a numerical example was presented for illustrative purposes.  相似文献   
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