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61.
运用我国1998年至2005年的相关指标数据,研究我国节能政策实施效果,建立我国节能政策绩效评价的指标体系。通过专家调查法和信息熵相结合的方法确定相关指标的权重,对我国节能政策绩效水平进行了评价。基于GM(1,1)模型,对我国节能政策绩效的相关指标进行了潜在态势预测,进行动态评价。  相似文献   
62.
模糊环境下考虑缺货和延期支付的Stackelberg均衡策略   总被引:1,自引:0,他引:1  
在具有价格弹性需求的两层供应链系统中,考虑到价格弹性指数的模糊性和供应链延期支付策略,建立了含缺货的制造商-零售商协调模型.运用符号距离反模糊化方法将其转化为确定模型.基于遗传算法,设计了其求解方法,获得了制造商最优信用期和零售商最优零售价.数值结果表明:模糊环境下的延期支付策略降低了产品的市场零售价,同时增加了供应链中各成员的利润,因此实现了供应链协调.进一步分析显示当模糊价格弹性指数的上(下)界变化反映出的不确定性减弱时,制造商提供更长的信用期,且制造商和零售商的利润均增加(减少).  相似文献   
63.
陈坚  张轶凡  洪集民 《管理科学》2019,22(10):72-81
当投资者预期未来股票市场可能出现下跌时,会用虚值看跌期权来对冲下跌风险,因此这部分期权价格中隐含了未来股票下跌风险的信息.文章根据下偏矩的概念,通过无模型的估计方法,从看跌期权价格中提取出股票收益率分布的尾部风险指标或下跌风险指标,发现其对未来1个月的股票超额收益率具有显著的预测能力.加入控制变量后,隐含尾部风险指标的预测能力依然十分稳健,说明该指标中含有其他预测因子中所不具备的额外预测信息.  相似文献   
64.
We present an evolutionary perspective on charismatic leadership, arguing that charisma has evolved as a credible signal of a person's ability to solve a coordination challenge requiring urgent collective action from group members. We suggest that a better understanding of charisma's evolutionary and biological origins and functions can provide a broader perspective in which to situate current debates surrounding the utility and validity of charismatic leadership as a construct in the social sciences. We outline several key challenges which have shaped our followership psychology, and argue that the benefits of successful coordination in ancestral environments has led to the evolution of context-dependent psychological mechanisms which are especially attuned to cues and signals of outstanding personal leadership qualities. We elaborate on several implications of this signaling hypothesis of charismatic leadership, including opportunities for deception (dishonest signaling) and for large-scale coordination.  相似文献   
65.
By using partial least squares path modeling, this paper develops a complex index of social capital, selects Croatia as the case for testing and validating the index, and investigates the regional distribution of social capital. The social capital index is defined as a complex hierarchical structured construct of third-order with social trust, participation, and civism as its core dimensions. The main results indicate that civism is the most important cause of social capital followed by active participation and social trust. As far as the regional distribution of social capital is concerned, there are statistically significant differences across the Croatian regions. Although the lowest or below the national average level of social capital and its dimensions can be mostly found in the least developed regions (with the exception of the capital), the highest level of social capital and its particular dimensions is not achieved in the most developed regions.  相似文献   
66.
Insight into measures of peakedness, heavy-tailedness, and kurtosis can be gained by studying Ruppert’s ratios of interquantile ranges. They are not only monotone in Horn’s measure of peakedness when applied to the central portion of the population, but also monotone in the practical tail-index of Morgenthaler and Tukey, when applied to the tails. Non-parametric confidence intervals are found for Ruppert’s ratios, and sample sizes required to obtain such intervals for a pre-specified relative width and level are provided. In addition, the empirical power of distribution-free tests for peakedness and bimodality are found for some symmetric distributions.  相似文献   
67.
The components of a reliability system subjected to a common random environment usually have dependent lifetimes. This paper studies the stochastic properties of such a system with lifetimes of the components following multivariate frailty models and multivariate mixed proportional reversed hazard rate (PRHR) models, respectively. Through doing stochastic comparison, we devote to throwing a new light on how the random environment affects the number of working components of a reliability system and on assessing the performance of a k-out-of-n system.  相似文献   
68.
An extended single‐index model is considered when responses are missing at random. A three‐step estimation procedure is developed to define an estimator for the single‐index parameter vector by a joint estimating equation. The proposed estimator is shown to be asymptotically normal. An algorithm for computing this estimator is proposed. This algorithm only involves one‐dimensional nonparametric smoothers, thereby avoiding the data sparsity problem caused by high model dimensionality. Some simulation studies are conducted to investigate the finite sample performances of the proposed estimators.  相似文献   
69.
This work considers two specific estimation techniques for the family-specific proportional hazards model and for the population-averaged proportional hazards model. So far, these two estimation procedures were presented and studied under the gamma frailty distribution mainly because of its simple interpretation and mathematical tractability. Modifications of both procedures for other frailty distributions, such as the inverse Gaussian, positive stable and a specific case of discrete distribution, are presented. By extensive simulations, it is shown that under the family-specific proportional hazards model, the gamma frailty model appears to be robust to frailty distribution mis-specification in both bias and efficiency loss in the marginal parameters. The population-averaged proportional hazards model, is found to be robust under the gamma frailty model mis-specification only under moderate or weak dependency within cluster members.  相似文献   
70.
提高居民的幸福指数是新常态下城市管理的重点工作。在综述以往研究的基础上,以需要层次论作为理论依据,整合2015年度安徽省统计年鉴数据完整、准确的指标,构建了安徽省城市居民幸福指数体系,经过数据收集、统计、分析和综合,得出16个城市居民综合幸福指数、基本需求幸福指数、发展需求幸福指数、享受需求幸福指数分值,对结果及其应用价值进行了讨论。  相似文献   
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