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   4385篇
  免费   176篇
  国内免费   88篇
财政金融   305篇
工业经济   176篇
计划管理   1123篇
经济学   885篇
综合类   755篇
运输经济   41篇
旅游经济   36篇
贸易经济   454篇
农业经济   412篇
经济概况   461篇
信息产业经济   1篇
  2024年   1篇
  2023年   38篇
  2022年   40篇
  2021年   69篇
  2020年   106篇
  2019年   66篇
  2018年   66篇
  2017年   87篇
  2016年   102篇
  2015年   109篇
  2014年   246篇
  2013年   313篇
  2012年   332篇
  2011年   415篇
  2010年   345篇
  2009年   310篇
  2008年   371篇
  2007年   368篇
  2006年   326篇
  2005年   202篇
  2004年   174篇
  2003年   137篇
  2002年   104篇
  2001年   74篇
  2000年   66篇
  1999年   38篇
  1998年   27篇
  1997年   18篇
  1996年   26篇
  1995年   10篇
  1994年   11篇
  1993年   6篇
  1992年   9篇
  1991年   12篇
  1990年   2篇
  1989年   4篇
  1988年   4篇
  1987年   5篇
  1986年   5篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1981年   1篇
排序方式: 共有4649条查询结果,搜索用时 15 毫秒
31.
外商直接投资对产业结构升级的作用机制研究   总被引:9,自引:0,他引:9  
姚君 《经济与管理》2005,19(11):41-43
随着知识经济时代的到来,产业结构升级成为现代经济发展中的焦点问题。外商投资起到了促进传统产业转移、新兴产业成长和产业组织结构优化等作用,并且带动了产业的调整和升级。但是,外商投资对于产业结构升级也存在一定的阻碍作用,通过研究外资对产业升级产生的影响,从而制定合理的引资政策具有十分重要的现实意义。  相似文献   
32.
The exact forms of the locally minimum variance unbiased estimators and their variances are given in the case of a discontinuous density function.  相似文献   
33.
Recent work on social status led to derivation of a new continuous distribution based on the exponential. The new variate, termed the ring(2)-exponential, in turn leads to derivation of two closely related new families of continuous distributions, the mirror-exponential and the ring-exponential. Both the standard exponential and the ring(2)-exponential are special cases of both the new families. In this paper, we first focus on the ring(2)-exponential, describing its derivation and examining its properties, and next introduce the two new families, describing their derivation and initiating exploration of their properties. The mirror-exponential arises naturally in the study of status; the ring-exponential arises from the mathematical structure of the ring(2)-exponential. Both have the potential for broad application in diverse contexts across science and engineering. Within sociobehavioral contexts, the new mirror-exponential may have application to the problem of approximating the form and inequality of the wage distribution.  相似文献   
34.
Following Parsian and Farsipour (1999), we consider the problem of estimating the mean of the selected normal population, from two normal populations with unknown means and common known variance, under the LINEX loss function. Some admissibility results for a subclass of equivariant estimators are derived and a sufficient condition for the inadmissibility of an arbitrary equivariant estimator is provided. As a consequence, several of the estimators proposed by Parsian and Farsipour (1999) are shown to be inadmissible and better estimators are obtained. Received January 2001/Revised May 2002  相似文献   
35.
This article develops a new method of estimating inefficiencies in joint production and shows that unlike the approaches utilized in the previous studies of inefficiency, this method maintains a consistent relationship between the error term of a profit function and the error terms of its price derivatives. A useful by-product of the method is a proof of a Hotelling-like lemma that relates stochastic input demand and output supply functions to stochastic profit functions. While the previous studies fit a single frontier to data on all firms, this paper estimates a frontier unique to every observed firm to allow each one to have a different potential of achieving maximal levels of profit. The new method is applied in the analysis of annual data, 1984–1989, for U.S. commercial banks. Both the analytical and numerical results of the paper show that the residual that the previous studies attribute to inefficiency includes the effects of excluded variables and of inaccuracies in the specified functional forms. Once accurate estimates of these effects are subtracted from the residual, the distortions in the measured inefficiencies should be considerably reduced. Consequently, this article considers how such estimates might be obtained.  相似文献   
36.
孤岛采油厂历经30多年的开发,已处于特高含水期产量递减阶段。由于新井产量受到自然资源和投资的限制是有限的,要减缓原油产量的递减,依靠的是大量增产措施的投入,而每项措施的实施需要耗费几万元到几十万元的费用。所以,引起开发后期油田成本上升的主要原因是油田增产措施难度加大,投入相应增加。为此,我们引入VE原理,科学实施增产措施工作量,达到了降低作业成本,提高增油效果的目的。  相似文献   
37.
The purpose of this paper is to discuss the use of Value Efficiency Analysis (VEA) in efficiency evaluation when preference information is taken into account. Value efficiency analysis is an approach, which applies the ideas developed for Multiple Objective Linear Programming (MOLP) to Data Envelopment Analysis (DEA). Preference information is given through the desirable structure of input- and output-values. The same values can be used for all units under evaluation or the values can be specific for each unit. A decision-maker can specify the input- and output-values subjectively without any support or (s)he can use a multiple criteria support system to assist him/her to find those values on the efficient frontier. The underlying assumption is that the most preferred values maximize the decision-maker's implicitly known value function in a production possibility set or a subset. The purpose of value efficiency analysis is to estimate a need to increase outputs and/or decrease inputs for reaching the indifference contour of the value function at the optimum. In this paper, we briefly review the main ideas in value efficiency analysis and discuss practical aspects related to the use of value efficiency analysis. We also consider some extensions.  相似文献   
38.
This paper proposes a general formulation of a nonparametric frontier model introducing external environmental factors that might influence the production process but are neither inputs nor outputs under the control of the producer. A representation is proposed in terms of a probabilistic model which defines the data generating process. Our approach extends the basic ideas from Cazals et al. (2002) to the full multivariate case. We introduce the concepts of conditional efficiency measure and of conditional efficiency measure of order-m. Afterwards we suggest a practical way for computing the nonparametric estimators. Finally, a simple methodology to investigate the influence of these external factors on the production process is proposed. Numerical illustrations through some simulated examples and through a real data set on Mutual Funds show the usefulness of the approach.JEL Classification: C13, C14, D20  相似文献   
39.
We propose a new bivariate distribution following a GLM form i.e., natural exponential family given the constantly correlated covariance matrix. The proposed distribution can represent an independent bivariate gamma distribution as a special case. In order to derive the distribution we utilize an integrating factor method to satisfy the integrability condition of the quasi-score function. The derived distribution becomes a mixture of discrete and absolute continuous distributions. The proposal of our new bivariate distribution will make it possible to develop some bivariate generalized linear models. Further the discrete correlated bivariate distribution will also arise from an independent bivariate Poisson mass function by compounding our proposed distribution (Iwasaki and Tsubaki, 2002).Received March 2003  相似文献   
40.
This paper introduces a flexible multiproduct cost function that permits zero values of one or more of the outputs and can impose restrictions quite easily, if not automatically satisfied, to ensure global concavity property. It satisfies linear homogeneity (in prices) property and is flexible in the output space. Thus the function is ideal for estimating, for example, economies of scope, cost complementarity, product-specific returns to scale, etc., without worrying about zero values of output(s) and extrapolations to points far from the point of approximation. As an empirical application, we use panel data (1978–1985) on 12 Finnish foundry plants to estimate technical progress, overall returns to scale, product-specific returns to scale and economies of scope.  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