首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   639篇
  免费   23篇
  国内免费   14篇
管理学   88篇
民族学   2篇
人口学   16篇
丛书文集   38篇
理论方法论   9篇
综合类   378篇
社会学   16篇
统计学   129篇
  2024年   5篇
  2023年   4篇
  2022年   10篇
  2021年   18篇
  2020年   21篇
  2019年   13篇
  2018年   16篇
  2017年   22篇
  2016年   28篇
  2015年   24篇
  2014年   48篇
  2013年   55篇
  2012年   36篇
  2011年   49篇
  2010年   38篇
  2009年   32篇
  2008年   38篇
  2007年   31篇
  2006年   22篇
  2005年   34篇
  2004年   27篇
  2003年   18篇
  2002年   8篇
  2001年   23篇
  2000年   8篇
  1999年   10篇
  1998年   8篇
  1997年   6篇
  1996年   2篇
  1995年   4篇
  1994年   4篇
  1993年   1篇
  1992年   5篇
  1991年   3篇
  1990年   1篇
  1989年   2篇
  1981年   1篇
  1979年   1篇
排序方式: 共有676条查询结果,搜索用时 15 毫秒
1.
Based on the environment-strategy performance perspective and dynamic capabilities framework, we develop a theoretical model and hypotheses specifying how supply chain collaboration as a response to environment context factors – competitive intensity, supply uncertainty, technological turbulence and market turbulence, using a lean and agile strategy may influence firm performance. We test the model using partial least square structural equation modelling on data collected from a field survey with responses from 152 manufacturing firms representing a variety of industries. Empirical findings generally support the relationship between collaboration and firm performance using a lean and agile strategy. Also, for firms in industries that face environments characterised by high supply uncertainty and competitive intensity with, technological turbulence, the study finds evidence of a direct relationship between these environmental factors and supply chain collaboration. The findings provide an initial strategic response framework for appropriately aligning a lean and agile supply chain strategy through collaboration with environment context factors to achieve firm performance improvements.  相似文献   
2.
Abstract.  Recurrent event data are largely characterized by the rate function but smoothing techniques for estimating the rate function have never been rigorously developed or studied in statistical literature. This paper considers the moment and least squares methods for estimating the rate function from recurrent event data. With an independent censoring assumption on the recurrent event process, we study statistical properties of the proposed estimators and propose bootstrap procedures for the bandwidth selection and for the approximation of confidence intervals in the estimation of the occurrence rate function. It is identified that the moment method without resmoothing via a smaller bandwidth will produce a curve with nicks occurring at the censoring times, whereas there is no such problem with the least squares method. Furthermore, the asymptotic variance of the least squares estimator is shown to be smaller under regularity conditions. However, in the implementation of the bootstrap procedures, the moment method is computationally more efficient than the least squares method because the former approach uses condensed bootstrap data. The performance of the proposed procedures is studied through Monte Carlo simulations and an epidemiological example on intravenous drug users.  相似文献   
3.
胡月晓 《南都学坛》2008,28(4):134-136
服务业FDI在FDI总量中的比重份额上升和变动幅度大,是近年来FDI变动的表现规律之一。服务业FDI具有地域限制、易受汇率风险影响、面临高的管理风险和波动性大的特征。影响服务业FDI的因素主要有收入增长、技术进步、金融发展以及投资和贸易政策变化。服务业FDI变动对经济活动的影响主要表现在带动FDI总量变动和影响产业结构调整两个方面。  相似文献   
4.
Summary. Earthquake intensities are modelled as a function of previous activity whose specific form is based on established empirical laws in seismology, but whose parameter values can vary from place to place. This model is used for characterizing regional features of seismic activities in and around Japan, and also for exploring regions where the actual seismicity rate systematically deviates from that of the modelled rate.  相似文献   
5.
强苯赛浸种对水稻幼苗的根长、根重和根系体积都有促进作用,能提高根尖细胞分裂指数,能使胚根尖切段伸长和发根力增强,并能提高胚乳中淀粉酶活性和根系的呼吸强度。  相似文献   
6.
Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.  相似文献   
7.
换韵与情绪宣泄关系十分密切,从王令《梦蝗》诗可以明显看到这一点。从《梦蝗》诗的换韵中人们可以有效地把握王令诗的情绪节奏变化特征,真正理解作为"蓄含悲愤"而又"笔力恣肆"诗人的情绪结构本质。  相似文献   
8.
This paper presents an empirical methodology for examining cost-adjusting in relation to multiple-output health care providers. The methodology is subsequently implemented using a sample of California outpatient clinics. The empirical evidence is that these clinics do cost-adjust; that is, the clinics respond to low Medicare reimbursement by using lower quality to control the marginal costs of those patient groups not insured under a government-sponsored plan. In addition, clinics do not cost-adjust with respect to Medi-Cal patients, implying that various government reimbursement systems have different effects on a provider’s cost-adjusting behavior.  相似文献   
9.
中国股票市场价格波动特征分析   总被引:4,自引:0,他引:4  
在股票市场中最令人捉摸不定,也最具有吸引力的是波动不已的股票价格。文章对中国股票市场价格波动的分析是从1997年9月展开至2002年10月,其间恰逢中国股市经历了一段从牛市的繁荣到熊市的萧条的过程,两种泾渭分明的市场氛围恰好提供了一个深入研究股票市场价格波动特征的有利契机。遵循经济控制论研究的思路,文章采用了理论分析、市场交易数据的实证研究等技术手段对中国股票市场价格波动进行了研究,通过运用经济控制论的方法建立理论模型,以上海股市和深圳股市的综合指数为样本,对中国股票市场系统本身的波动特征和稳定性进行了量化分析。  相似文献   
10.
Abstract A model is introduced here for multivariate failure time data arising from heterogenous populations. In particular, we consider a situation in which the failure times of individual subjects are often temporally clustered, so that many failures occur during a relatively short age interval. The clustering is modelled by assuming that the subjects can be divided into ‘internally homogenous’ latent classes, each such class being then described by a time‐dependent frailty profile function. As an example, we reanalysed the dental caries data presented earlier in Härkänen et al. [Scand. J. Statist. 27 (2000) 577], as it turned out that our earlier model could not adequately describe the observed clustering.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号