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   26369篇
  免费   516篇
  国内免费   13篇
财政金融   4796篇
工业经济   2114篇
计划管理   4191篇
经济学   5707篇
综合类   455篇
运输经济   163篇
旅游经济   435篇
贸易经济   4384篇
农业经济   1410篇
经济概况   3206篇
信息产业经济   2篇
邮电经济   35篇
  2020年   266篇
  2019年   370篇
  2018年   483篇
  2017年   504篇
  2016年   474篇
  2015年   329篇
  2014年   490篇
  2013年   2575篇
  2012年   626篇
  2011年   702篇
  2010年   652篇
  2009年   737篇
  2008年   772篇
  2007年   681篇
  2006年   597篇
  2005年   616篇
  2004年   525篇
  2003年   570篇
  2002年   496篇
  2001年   514篇
  2000年   512篇
  1999年   490篇
  1998年   493篇
  1997年   507篇
  1996年   535篇
  1995年   474篇
  1994年   459篇
  1993年   448篇
  1992年   457篇
  1991年   460篇
  1990年   409篇
  1989年   349篇
  1988年   311篇
  1987年   315篇
  1986年   373篇
  1985年   515篇
  1984年   528篇
  1983年   501篇
  1982年   462篇
  1981年   469篇
  1980年   398篇
  1979年   427篇
  1978年   338篇
  1977年   319篇
  1976年   264篇
  1975年   240篇
  1974年   229篇
  1973年   195篇
  1972年   164篇
  1971年   141篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Summary A sequential testing procedure called 2-SPRT for the meanμ of the negative binomial distribution with known exponentk is presented. For any fixedμ 0(μ 1<μ 0<μ 2), the 2-SPRT provides an asymptotic solution to the modified Kiefer-Weiss problem. Determination ofμ 0 such that the test provides an approximate solution to the Kiefer-Weiss problem is described. The behavior of the 2-SPRT and the Sequential Probability Ratio Test is investigated using Monte Carlo methods. The error probabilities and the average sample numbers are compared. All the computations were carried out on the Alabama Supercomputer.  相似文献   
32.
The literature on industrial organization contains very little direct evidence on the effects of actual mergers. This study estimates the effects of two recent airline mergers approved by the Department of Transportation over the objection of the Department of Justice. The merger of TWA and Ozark appears to have caused a slight increase in fares and a far greater reduction in service on city pairs out of St Louis. The merger of Northwest and Republic appears to have caused a significant increase in fares and a significant reduction in overall service on city pairs out of Minneapolis-St Paul.  相似文献   
33.
Whilst the local multiplier impacts of the annual operation of universities has been the subject of intensive research, the economic impacts of capital construction projects have been almost completely ignored. This paper presents the results of detailed analysis of capital projects at Lancaster University in 1993-The reasons for the radically different annual operation and construction multipliers estimated in the Lancaster study are examined. Despite the smaller size of construction multipliers it is argued that it is a serious mistake to estimate local construction multipliers by making simplifying assumptions on the size of the key parameters in the multiplier equations.  相似文献   
34.
A study of the location of three classifications of high-tech industries in rural areas was undertaken using ordinary least squares, Tobit, and a two-step estimation procedure suggested by Heckman (1976). The results indicate that the location decision for high tech firms is influenced primarily by the county population, adjacency to an SMSA, and the expenditures on public infrastructure (exclusive of education expenditures). However, location near interstate highways was generally not a significant factor. Results were similar between branch and unit (single ownership) plants. Some differences in signs of orders of magnitude occurred among the estimation procedures. Making a choice between Tobit and Heckman approaches depends upon the goal of the research.  相似文献   
35.
Optimal investment rules are developed for a producer agency investing in domestic-market generic advertising, export market promotion, and cost-of-production-reducing research. These rules are derived assuming either maximization of producers' surplus or social surplus. The form of the optimality rules differs according to which objective is pursued. Fixed producer agency budgets are also allowed by incorporating a constraint limiting total expenditure on the three activities. Addition of such a constraint substantially alters the structure of the optimal investment rules. Differences in these rules highlight the importance of accounting for the financing mechanism when modeling optimal checkoff fund investment decisions. Optimality rules are simulated using data for the Canadian beef sector. Results suggest historic underinvestment in domestic-market generic advertising but overinvestment in export market promotion. Sensitivity of simulation results underscores the difficulty in assessing optimality of historic producer investment in cost-of-production-reducing research.  相似文献   
36.
H erbert G iersch (ed.) New Opportunities for Entrepreneurship . Tübingen: Mohr, 1984, pp. 262 + vi, DM62 (paperback). C yril L evicki  相似文献   
37.
38.
39.
Book Review     
Books reviewed:
Ira A. Jackson and Jane Nelson, Profits with Principles: Seven Strategies for Delivering Values with Values .  相似文献   
40.
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