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1.
卫所制度是明清时期重要的军政制度。以浙江沿海明清卫所驻地方言为考察对象,从北到南选取了最有代表性的16个方言点,通过共时和历时的比较,分析和总结浙江沿海明清卫所驻地方言声母在数量和古今分合上的特点。  相似文献   
2.
在一定假设条件下,利用数理经济学方法对区域经济运行中的纯粹交换经济系统、纯粹生产经济系统、生产--交换经济系统中的资源地域空间配置优化进行一般均衡及其均衡扩展比较研究,发现并证明无论何种类型的区域经济体系或多区域经济体系,资源地域空间配置优化的宏观经济效益与微观经济效益并不总是一致的,存在着差异与负相关的可能性.  相似文献   
3.
Herein, we propose a data-driven test that assesses the lack of fit of nonlinear regression models. The comparison of local linear kernel and parametric fits is the basis of this test, and specific boundary-corrected kernels are not needed at the boundary when local linear fitting is used. Under the parametric null model, the asymptotically optimal bandwidth can be used for bandwidth selection. This selection method leads to the data-driven test that has a limiting normal distribution under the null hypothesis and is consistent against any fixed alternative. The finite-sample property of the proposed data-driven test is illustrated, and the power of the test is compared with that of some existing tests via simulation studies. We illustrate the practicality of the proposed test by using two data sets.  相似文献   
4.
英汉基本句类主位结构对比及翻译   总被引:2,自引:0,他引:2  
从语篇分析的角度,运用系统功能语法理论,通过对英汉基本句类的主述位结构的对比分析,探讨如何在翻译中处理主述位错位现象的问题。  相似文献   
5.
从中外水利教育的管理、教学、科研及产学研相结合方面进行了比较研究,并提出了相应的结论和建议。  相似文献   
6.
Summary.  We detail a general method for measuring agreement between two statistics. An application is two ratios of directly standardized rates which differ only by the choice of the standard. If the statistics have a high value for the coefficient of agreement then the expected squared difference between the statistics is small relative to the variance of the average of the two statistics, and inferences vary little by changing statistics. The estimation of a coefficient of agreement between two statistics is not straightforward because there is only one pair of observed values, each statistic calculated from the data. We introduce estimators of the coefficient of agreement for two statistics and discuss their use, especially as applied to functions of standardized rates.  相似文献   
7.
The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
8.
会计要素划分的国际比较   总被引:1,自引:0,他引:1  
会计要素理论在会计准则理论框架中居于核心地位,但各国由于环境因素等方面的差异,规定的会计要素并不完全相同。在对美国财务会计准则委员会(FASB)、英国会计准则委员会(ASB)、国际会计准则委员会(IASC)和我国对会计要手划分比较的基础上,提出在现有要素体系基础上应增加现金流量表要素。  相似文献   
9.
在高等教育投入的多元化趋势中,伴随着高校收费政策的实施,学生资助问题成为国家宏观教育政策关注的重点领域。本文在国际高等教育投入和学生资助模式比较分析的基础上,对我国高等教育学费和学生资助提出政策建议。争取除学费外的其他社会投入应成为中国进一步筹措高等教育经费的重点;在确定高等教育学费时应兼顾培养成本和人均收入水平;同时要建立和完善多元化的学生资助体系。  相似文献   
10.
Abstract.  In this paper, we study the statistical interpretation of forensic DNA mixtures with related contributors in subdivided populations. Compact general formulae for match probabilities are obtained for two situations: a relative of one tested person is an unknown contributor of a DNA mixture; and two related unknowns are contributors. The effect of kinship and population structure is illustrated using a real case example.  相似文献   
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