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41.
解体之后的哲学在俄罗斯遭到了前所未有的冷落,它既面临着俄罗斯是否还需要哲学的问题,又面临着被终结的可能,但是俄罗斯哲学以自己一贯的优秀品质在低靡的社会现实中艰难地跋涉,关注着一些积极而有意义的同社会生活密切相关的问题。暂时摆脱意识形态束缚的俄罗斯哲学,更加清醒理智地期待哲学的美好未来。 相似文献
42.
弱势群体不仅存在于经济落后的国家,而且存在于经济发达国家,不仅存在于计划经济体制国家,而且存在于市场经济体制国家。各国政府基于公平和效率的考虑,都把经济困难群体的教育资助视为其基本职责之一。本文对美国、日本、巴西等国政府对弱势群体的教育资助制度和方式进行分析。 相似文献
43.
文章运用转换生成语法中的某些句法理论,对助动词的一些结构特征进行分析,如助动词作为INFL,空位助动词,助动词作为屈折语的提升,助动词与主语论旨角色的分配,多个助动词在句中出现时的排列顺序等。 相似文献
44.
文章理论联系实际,比较系统总结了华中农业大学“两课”建设与改革的经验:高度重视,加强领导,整体规划,加大投入;开齐课程,加强建设,精选教材,抓好落实;重视教师队伍建设,不断加强培训提高;深化教学改革,教改成绩突出,教学效果显著。 相似文献
45.
Computing maximum likelihood estimates from type II doubly censored exponential data 总被引:1,自引:0,他引:1
Arturo J. fernández José I. Bravo Íñigo De Fuentes 《Statistical Methods and Applications》2002,11(2):187-200
It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions
of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp
lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods
such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived.
In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest
posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included. 相似文献
46.
笔者通过对花溪镇第四居委会的社区建设情况的问卷调查 ,了解到该社区居民的需求状况、以及社区服务与管理的现状 ,根据对本次实地调查结果的分析 ,为花溪镇政府的城市社区建设方案提出了一些切实可行的建议。笔者认为花溪镇政府在制定社会建设总体目标时应以花溪旅游目的地为特征 ,以居民认同感和归属感为纽带 ,以社区党建为核心 ,以居委会为依托 ,以社区成员自治为重点 ,以强化社区动能 ,提高社区居民生活质量为目的。在加强社区组织的建设和管理 ,培养两支社区服务队伍和作好广泛社区建设宣传动员等工作的基础上 ,把花溪建设成为现代旅游目的地社区 相似文献
47.
Carmen Fernández Eduardo Ley Mark F. J. Steel 《Journal of the Royal Statistical Society. Series C, Applied statistics》2002,51(3):257-280
Summary. We model daily catches of fishing boats in the Grand Bank fishing grounds. We use data on catches per species for a number of vessels collected by the European Union in the context of the Northwest Atlantic Fisheries Organization. Many variables can be thought to influence the amount caught: a number of ship characteristics (such as the size of the ship, the fishing technique used and the mesh size of the nets) are obvious candidates, but one can also consider the season or the actual location of the catch. Our database leads to 28 possible regressors (arising from six continuous variables and four categorical variables, whose 22 levels are treated separately), resulting in a set of 177 million possible linear regression models for the log-catch. Zero observations are modelled separately through a probit model. Inference is based on Bayesian model averaging, using a Markov chain Monte Carlo approach. Particular attention is paid to the prediction of catches for single and aggregated ships. 相似文献
48.
主要针对现阶段我国城市化所面临的几个主要问题和障碍 ,拟出一些对策方法。其中主要有关于城市化进程阶段性目标的制订 ,城市化道路的正确选择 ,户籍管理制度的改革 ,产业结构的转换和升级 ,区域经济的协调发展 ,以及农村经济、城市经济的发展和城市管理体制改革等对策措施。 相似文献
49.
If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000. 相似文献
50.
Craig H. Mallinckrodt Christopher J. Kaiser John G. Watkin Michael J. Detke Geert Molenberghs Raymond J. Carroll 《Pharmaceutical statistics》2004,3(3):171-186
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