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   27684篇
  免费   661篇
  国内免费   3篇
财政金融   4822篇
工业经济   1818篇
计划管理   4833篇
经济学   6596篇
综合类   471篇
运输经济   199篇
旅游经济   398篇
贸易经济   4645篇
农业经济   1267篇
经济概况   3165篇
信息产业经济   7篇
邮电经济   127篇
  2023年   120篇
  2021年   273篇
  2020年   332篇
  2019年   487篇
  2018年   694篇
  2017年   741篇
  2016年   725篇
  2015年   422篇
  2014年   635篇
  2013年   2572篇
  2012年   1241篇
  2011年   1259篇
  2010年   939篇
  2009年   979篇
  2008年   946篇
  2007年   824篇
  2006年   902篇
  2005年   1605篇
  2004年   967篇
  2003年   663篇
  2002年   489篇
  2001年   557篇
  2000年   493篇
  1999年   436篇
  1998年   483篇
  1997年   423篇
  1996年   400篇
  1995年   362篇
  1994年   364篇
  1993年   350篇
  1992年   350篇
  1991年   367篇
  1990年   336篇
  1989年   240篇
  1988年   255篇
  1987年   259篇
  1986年   242篇
  1985年   355篇
  1984年   356篇
  1983年   332篇
  1982年   289篇
  1981年   284篇
  1980年   277篇
  1979年   272篇
  1978年   219篇
  1977年   179篇
  1976年   181篇
  1975年   157篇
  1974年   148篇
  1973年   145篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
A statistically optimal inference about agents' ex ante price expectations within the US broiler market is derived using futures prices of related commodities along with a quasi‐rational forecasting regression equation. The modelling approach, which builds on a Hamilton‐type framework, includes endogenous production and allows expected cash price to be decomposed into anticipated and unanticipated components. We therefore infer the relative importance of various informational sources in expectation formation. Results show that, in addition to the quasi‐rational forecast, the true supply shock, future prices, and ex post commodity price forecast errors have, at times, been influential in broiler producers' price expectations. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
92.
above the certainty level while for additive uncertainty the price should be lower than the certainty level. This note gives an intuitive explanation for the result after first presenting a parsimonious review of the two models. We also discuss which, if either, of the two models is more realistic. Received December 14, 2001; revised version received July 16, 2002 Published online: April 30, 2003 We thank referees for helpful comments. Ciaran Driver would like to acknowledge the research facilities from ANU, Canberra for their help in writing this paper.  相似文献   
93.
94.
The Amazon is the largest tropical forest area on Earth, and has been undergoing rapid deforestation for the last four decades. In the Brazilian Amazon, large‐scale pasture for cattle ranching and soybean production are the main land uses, leading to a yearly deforestation rate of 0.5%. These conversions are mostly located in frontier areas distributed along the so‐called “arc of deforestation”. Within this large zone, various land use change processes are interacting through several modes of land valuation and organisation. From several case studies in the State of Pará (Brazil), the current project aims at analysing how landscape dynamics are related to infrastructure development, ecological conditions, zoning policies and to the evolution and the organisation of the production, consumption and marketing chains of livestock products. This paper presents the results for one test site, the region of São Félix do Xingú, South of Pará This region is the focus of land speculation, cattle expansion, and deforestation. Road construction, investments in electrical energy, financial credit for cattle, and the land reform policies have all fuelled this process. All these factors make this region one of the most dynamic agricultural frontiers in the Brazilian Amazon. The main objective of the paper is to improve our understanding of deforestation processes by crossing spatial analyses and 1ivestock economics.studies, and to characterise the role and impact of various natural and anthropic factors in the location and development of the main types of farmers, and their policy implications.  相似文献   
95.
We evaluate the appropriateness of regulation within the Canadian cable television industry by applying both parametric and non-parametric approachesto measure scale efficiency. Although we begin with a sample offering adequatedegrees of freedom for parametric estimation, important policy issues lead us toconsider further estimation over sub-samples. Since some of these sub-samplesare small enough that parametric models cannot guarantee reliable estimates, weobtain production characteristics non-parametrically through data envelopmentanalysis. The nonparametric results for scale efficiency support the parametricresults. We find evidence against a natural monopoly argument that might havejustified continuation of the mandated monopolization of Canadian cable televisionservice. By the end of the sample period, there were no longer substantial economiesof scale in most relevant markets.  相似文献   
96.
97.
98.
99.
An algorithm is described to compute equilibria of the general economic model with incomplete asset markets, that is, of GEI. The algorithm is based on the existence of a route of zeros of a homotopy whose domain includes the price simplex and a Grassmann Manifold. This route is followed, in effect, by localizing and following diffeomorphic pieces in Euclidean space, and by relocalizing as is necessary.  相似文献   
100.
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