全文获取类型
收费全文 | 1243篇 |
免费 | 45篇 |
专业分类
管理学 | 153篇 |
民族学 | 8篇 |
人口学 | 50篇 |
丛书文集 | 117篇 |
理论方法论 | 34篇 |
综合类 | 434篇 |
社会学 | 65篇 |
统计学 | 427篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 17篇 |
2020年 | 14篇 |
2019年 | 20篇 |
2018年 | 29篇 |
2017年 | 37篇 |
2016年 | 22篇 |
2015年 | 28篇 |
2014年 | 49篇 |
2013年 | 199篇 |
2012年 | 88篇 |
2011年 | 80篇 |
2010年 | 60篇 |
2009年 | 85篇 |
2008年 | 61篇 |
2007年 | 65篇 |
2006年 | 98篇 |
2005年 | 63篇 |
2004年 | 59篇 |
2003年 | 55篇 |
2002年 | 35篇 |
2001年 | 32篇 |
2000年 | 24篇 |
1999年 | 6篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 2篇 |
排序方式: 共有1288条查询结果,搜索用时 187 毫秒
171.
Multiple imputation (MI) is an appealing option for handling missing data. When implementing MI, however, users need to make important decisions to obtain estimates with good statistical properties. One such decision involves the choice of imputation model–the joint modeling (JM) versus fully conditional specification (FCS) approach. Another involves the choice of method to handle interactions. These include imputing the interaction term as any other variable (active imputation), or imputing the main effects and then deriving the interaction (passive imputation). Our study investigates the best approach to perform MI in the presence of interaction effects involving two categorical variables. Such effects warrant special attention as they involve multiple correlated parameters that are handled differently under JM and FCS modeling. Through an extensive simulation study, we compared active, passive and an improved passive approach under FCS, as JM precludes passive imputation. We additionally compared JM and FCS techniques using active imputation. Performance between active and passive imputation was comparable. The improved passive approach proved superior to the other two particularly when the number of parameters corresponding to the interaction was large. JM without rounding and FCS using active imputation were also mostly comparable, with JM outperforming FCS when the number of parameters was large. In a direct comparison of JM active and FCS improved passive, the latter was the clear winner. We recommend improved passive imputation under FCS along with sensitivity analyses to handle multi-level interaction terms. 相似文献
172.
双宾语在现代汉语中占据着一个非常重要的地位,比较现代汉语和英语中双宾语结构构成的异同,有助于我们更好地学习并利用现代汉语中的双宾语结构,也有助于理解和学习英语中的双宾语结构。本文先后探讨了现代汉语和英语中双宾语在结构上、动词、直接宾语、间接宾语方面的异同,对我们更好地学习和运用现代汉语中的双宾语有一定的帮助。 相似文献
173.
就业是民生之基,是社会稳定之本,也是女性劳动者的基本权利、提高女性自身经济地位的重要手段,更是性别平等的测试器。在四川省甘孜州、阿坝州,城镇女性从业者在教育、卫生等行业有较高从业优势,就业集中分布于公共管理、教育、卫生、文化等领域,在零售、餐饮、住宿等市场化行业的集中度不明显;产业结构、城镇化与乡城劳动力转移、民营经济发展水平、城镇女性人力资本以及择业观念等影响城镇女性的行业就业行为;传统服务业与线上业态、旅游相关产业、生态红利产业、农业产业链延伸产业等是未来城镇女性劳动力的就业拓展领域;提升女性人力资本有助于女性从业者的就业结构优化。 相似文献
174.
State fragility is a concept that entered the political discourse in the last decades producing remarkable implications for aid allocation and international policies. The operationalization of this concept has generated a number of composite indices to produce rankings of fragile states. However, the temporal dimension of the driving forces leading to fragility has been rather neglected. This article discusses a statistical procedure that helps to represent the global fragility of a country and the path that a country has followed or will follow in the future when possibly entering into (or escaping from) a fragility condition. Specifically, multiple factor analysis is applied to depict vulnerable and weak countries, and to identify the fundamental forces that determine their overall fragility. Moreover, the trajectories of countries along the years are estimated using partial factor scores. Finally, the path of each country is predicted by means of parsimonious regression models, based on a reduced set of explanatory variables, and according to scenarios elaborated from available international outlooks. 相似文献
175.
In this paper we propose a new method for studying local and global clustering in networks employing random walk pairs. The method is intuitive and directly generalizes standard local and global clustering coefficients to weighted networks and networks containing nodes of multiple types. In the case of two-mode networks the values obtained for commonly considered social networks are in sharp contrast to those obtained, for instance, by the method of Opsahl (2013), and provide a different viewpoint for clustering. The approach is also applicable in questions related to the general study of segregation and homophily. Applications to existent data sets are considered. 相似文献
176.
《Omega》2016
The multiple criteria ABC analysis is widely used in inventory management, and it can help organizations to assign inventory items into different classes with respect to several evaluation criteria. Many approaches have been proposed in the literature for addressing such a problem. However, most of these approaches are fully compensatory in multiple criteria aggregation. This means that an item scoring badly on one or more key criteria could be placed in good classes because these bad performances could be compensated by other criteria. Thus, it is necessary to consider the non-compensation in the multiple criteria ABC analysis. To the best of our knowledge, the ABC classification problem with non-compensation among criteria has not been studied sufficiently. We thus propose a new classification approach based on the outranking model to cope with such a problem in this paper. However, the relational nature of the outranking model makes the search for the optimal classification solution a complex combinatorial optimization problem. It is very time-consuming to solve such a problem using mathematical programming techniques when the inventory size is large. Therefore, we combine the clustering analysis and the simulated annealing algorithm to search for the optimal classification. The clustering analysis groups similar inventory items together and builds up the hierarchy of clusters of items. The simulated annealing algorithm searches for the optimal classification on different levels of the hierarchy. The proposed approach is illustrated by a practical example from a Chinese manufacturer. Furthermore, we validate the performance of the approach through experimental investigation on a large set of artificially generated data at the end of the paper. 相似文献
177.
经济转型不仅使中俄两国的经济体制发生了重大转变,而且使两国的经济结构发生了深刻调整。俄罗斯不仅形成了混乱的市场体制和分裂的社会结构,而且形成了一种去工业化、去现代化的资源依赖型经济结构。中国在转型进程中形成的是一种政府主导的可控的市场经济社会,并处于工业化的迅速爬升阶段。导致中俄两国经济结构差异的一个关键因素就是国家制度能力。一个能力充分的国家能够根据内外环境的变化对经济结构进行适应性调整,实现社会经济持续、快速、平衡发展的目标;反之,则可能导致经济结构退化,经济发展停滞,乃至国家竞争优势的丧失。后危机时代,中俄两国依然面临着深化经济转型和推进发展模式转变的重任,如何塑造适宜的国家制度能力,是推动经济结构进一步调整优化的重要动力。 相似文献
178.
179.
中国传媒在国际传播格局中处于弱势,为了全面提升中国传媒的国际传播力,要制定国家文化发展战略,树立文化传播的主体意识;争夺有效话语权;提升对外翻译的影响力;借鉴国外媒体的经验、现成的国际传播渠道,提高与境外媒体打交道的能力;构建合理的现代传播体系,打造国际一流媒体。 相似文献
180.