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61.
本文从与发展内涵相关的人类发展的诸项指数、国家实力概念的探讨情况,论述了民族素质在现代发展概念中的重要地位.  相似文献   
62.
Du  Hongfei  Zhou  Nan  Cao  Hongjian  Zhang  Jintao  Chen  Anli  King  Ronnel B. 《Social indicators research》2021,154(3):789-813
Social Indicators Research - Previous studies have documented the associations of objective class with either social capital or subjective social status, yet little attention has been paid to the...  相似文献   
63.
In this article, we propose a factor-adjusted multiple testing (FAT) procedure based on factor-adjusted p-values in a linear factor model involving some observable and unobservable factors, for the purpose of selecting skilled funds in empirical finance. The factor-adjusted p-values were obtained after extracting the latent common factors by the principal component method. Under some mild conditions, the false discovery proportion can be consistently estimated even if the idiosyncratic errors are allowed to be weakly correlated across units. Furthermore, by appropriately setting a sequence of threshold values approaching zero, the proposed FAT procedure enjoys model selection consistency. Extensive simulation studies and a real data analysis for selecting skilled funds in the U.S. financial market are presented to illustrate the practical utility of the proposed method. Supplementary materials for this article are available online.  相似文献   
64.
Lv  Hailiang  Yang  Yanbo  Zhang  Dan  Du  Hongju  Zhang  Jianyu  Wang  Wenjie  He  Xingyuan 《Urban Ecosystems》2019,22(4):631-642

To maximize the ecological services of urban forests, a better understanding of the effects of urbanization on urban forest characteristics, landscape metrics, and their associations is needed for landscape-related regulations in space-limited green infrastructure of metropolitan regions. In this study, Harbin, a typical fast-growing provincial-capital city in Northeast China, is used as a case study. Based on remote sensing images, field surveys, and correlation and variation partitioning analyses, we conclude that landscape characteristics and forest attributes have large variations among different urbanization intensity (UI) regions. Forest patch density (PD), landscape shape index, woody plants species richness, and the Shannon–Wiener index (H′) increased linearly, while stem section area and tree height decreased linearly with the increasing of UIs. UI had a greater influence on tree size and forest community attributes than the forest landscape pattern. Accordingly, any landscape regulation on forest attributes should be implemented according to UIs. In addition, Euclidean nearest neighbor distance(ENN-MN), mean perimeter-area ratio (PARA-MN), fractal dimension index(FRAC-MN), and PD could probably indicate forest attributes the most, e.g., the increase of PARA-MN may be accompanied with taller trees in low and heavy UI regions, but lower woody plants species evenness in low and medium UI regions. More diversified woody plants species, and afforested areas should be advocated in a low UI region, while in a heavy UI region, the conservation of large trees should be implemented. Our results highlight that the implementation of urban forest management should vary according to different urbanization regions to maximize ecological services.

  相似文献   
65.
阿拉善蒙古与清廷联姻述评   总被引:1,自引:0,他引:1  
阿拉善蒙古是清朝皇帝实行政治联姻的重点部落,有清一代,该部与清皇家的婚姻始终不断。本文以清皇家族谱《玉牒》为主,结合其他文献,对阿拉善蒙古与清皇家的联姻情况作了比较全面的揭示,并对联姻的特点及其与清朝统治的关系以及由此产生的满、蒙古、汉血缘融合等问题进行了分析。  相似文献   
66.
人民群众观是关于人民群众是谁、如何看待人民群众、怎样处理与人民群众关系等一系列重大问题思想认识的理论形态。李大钊基于坚定的人民立场和真挚的人民情怀,以唯物史观为认识工具,以中国实际和中国革命进程为现实基础,以人的平等、自由、富庶为终极价值目标,以"平民主义"为核心范畴,构建起属于马克思主义谱系的人民群众观。在"Democracy"的多种汉译词语中,李大钊主选了"平民主义"。在李大钊的语境中,"平民"一指集合意义上的人民,二指占社会成员或国民绝大多数的普通民众,三指平等、自由之民。李大钊"平民"范畴的多义性决定了其"平民主义"意蕴的多维性。以"平民主义"为核心范畴的李大钊人民群众观的思想主张主要有:爱民忧民重民生,人民是历史的主体,人民是真正的英雄,人民亟需教育、组织和训练,没有妇女的解放就没有人类的解放,知识青年须走与民众相结合的道路等。李大钊是中国近现代之交新型人民群众观的开创者,是中国共产党人民群众观的奠基人。  相似文献   
67.
Statistical inference for the diffusion coefficients of multivariate diffusion processes has been well established in recent years; however, it is not the case for the drift coefficients. Furthermore, most existing estimation methods for the drift coefficients are proposed under the assumption that the diffusion matrix is positive definite and time homogeneous. In this article, we put forward two estimation approaches for estimating the drift coefficients of the multivariate diffusion models with the time inhomogeneously positive semidefinite diffusion matrix. They are maximum likelihood estimation methods based on both the martingale representation theorem and conditional characteristic functions and the generalized method of moments based on conditional characteristic functions, respectively. Consistency and asymptotic normality of the generalized method of moments estimation are also proved in this article. Simulation results demonstrate that these methods work well.  相似文献   
68.
白仲林  杜阳  柳颖 《统计研究》2017,(6):96-108
为了揭示政府采购市场的定价机制,探究招标活动的经济机理,本文首先提出了一种基于可观测成交价(即赢价)建立招标结构模型的方法,分析了博弈均衡的分布;然后讨论了该模型的非参数识别,提出了一种三阶段非参数核估计方法.最后,以中央单位集中采购打印机为例,估计了政府采购招标的成本分布和期望供给曲线.研究发现,当前的政府采购机制改革有效地降低了采购成本;对于附加成本较高的商品,投标人存在成本转移行为.  相似文献   
69.
70.
The gist of the quickest change-point detection problem is to detect the presence of a change in the statistical behavior of a series of sequentially made observations, and do so in an optimal detection-speed-versus-“false-positive”-risk manner. When optimality is understood either in the generalized Bayesian sense or as defined in Shiryaev's multi-cyclic setup, the so-called Shiryaev–Roberts (SR) detection procedure is known to be the “best one can do”, provided, however, that the observations’ pre- and post-change distributions are both fully specified. We consider a more realistic setup, viz. one where the post-change distribution is assumed known only up to a parameter, so that the latter may be misspecified. The question of interest is the sensitivity (or robustness) of the otherwise “best” SR procedure with respect to a possible misspecification of the post-change distribution parameter. To answer this question, we provide a case study where, in a specific Gaussian scenario, we allow the SR procedure to be “out of tune” in the way of the post-change distribution parameter, and numerically assess the effect of the “mistuning” on Shiryaev's (multi-cyclic) Stationary Average Detection Delay delivered by the SR procedure. The comprehensive quantitative robustness characterization of the SR procedure obtained in the study can be used to develop the respective theory as well as to provide a rational for practical design of the SR procedure. The overall qualitative conclusion of the study is an expected one: the SR procedure is less (more) robust for less (more) contrast changes and for lower (higher) levels of the false alarm risk.  相似文献   
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