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   406篇
  免费   4篇
财政金融   87篇
工业经济   35篇
计划管理   70篇
经济学   72篇
综合类   2篇
运输经济   1篇
旅游经济   1篇
贸易经济   86篇
农业经济   3篇
经济概况   53篇
  2023年   4篇
  2019年   3篇
  2018年   6篇
  2017年   4篇
  2016年   4篇
  2015年   5篇
  2014年   3篇
  2013年   35篇
  2012年   13篇
  2011年   18篇
  2010年   10篇
  2009年   10篇
  2008年   6篇
  2007年   11篇
  2006年   5篇
  2005年   13篇
  2004年   8篇
  2003年   12篇
  2002年   4篇
  2000年   4篇
  1999年   5篇
  1997年   6篇
  1996年   8篇
  1995年   7篇
  1994年   7篇
  1993年   6篇
  1992年   3篇
  1991年   4篇
  1990年   5篇
  1988年   3篇
  1987年   7篇
  1986年   7篇
  1985年   8篇
  1984年   10篇
  1983年   10篇
  1982年   7篇
  1981年   11篇
  1980年   9篇
  1979年   11篇
  1978年   10篇
  1977年   11篇
  1976年   9篇
  1975年   8篇
  1974年   4篇
  1973年   8篇
  1972年   8篇
  1971年   5篇
  1968年   3篇
  1967年   5篇
  1930年   2篇
排序方式: 共有410条查询结果,搜索用时 15 毫秒
81.
Here Herbert Northrup Duncan Campbell discuss an article published in this Journal (Vol 17 No 2 Summer 1986)-the author subsequently responds to their comments.  相似文献   
82.
Herbert Vogt 《Metrika》1996,44(1):207-221
Let ζ t be the number of events which will be observed in the time interval [0;t] and define as the average number of events per time unit if this limit exists. In the case of i.i.d. waiting-times between the events,E t ] is the renewal function and it follows from well-known results of renewal theory thatA exists and is equal to 1/τ, if τ>0 is the expectation of the waiting-times. This holds true also when τ = ∞.A may be estimate by ζ t /t or where is the mean of the firstn waiting-timesX 1,X 2, ...,X n . Both estimators converage with probability 1 to 1/τ if theX i are i.i.d.; but the expectation of may be infinite for alln and also if it is finite, is in general a positively biased estimator ofA. For a stationary renewal process, ζ t /t is unbiased for eacht; if theX i are i.i.d. with densityf(x), then ζ t /t has this property only iff(x) is of the exponential type and only for this type the numbers of events in consecutive time intervals [0,t], [t, 2t], ... are i.i.d. random variables for arbitraryt > 0.  相似文献   
83.
ABSTRACT

The projected global expansion in consumption of meat and other livestock products potentially offers sub-Saharan African small-holder farmers opportunities to escape from the poverty trap. A necessary condition for exploiting this potential is the establishment of marketing systems that provide farmers with reasonable incentives to participate in the market. In this study, the functioning of livestock markets in rural Uganda is analyzed based on a survey of 401 livestock keepers, complimented with focus group discussions with livestock traders and policy planners. The first part is dedicated to the empirical analysis of key organizational and institutional arrangements. Constraints along the marketing chain as well as potential institutional solutions are illuminated. The second part is dedicated to propositions of new areas where more work and new results are needed to improve the functioning of the livestock marketing chain. Empirical findings indicated the following institutional constraints: a poor market information system, lack of grades and standards, lack of trade finance, poor contract enforcement and dispute settlement, disorganized actors, high transaction risks, and poorly developed marketing infrastructure. The study recommends a structured approach to livestock marketing, market infrastructure development, and emphasis on arbitration systems as specific ways of improving the efficiency of livestock marketing in Uganda and other developing countries.  相似文献   
84.
In August, 2010, the Antitrust Division and the Federal Trade Commission issued new Guidelines for assessing horizontal mergers under the antitrust laws. These Guidelines were long awaited not merely because of the lengthy interval between them and previous Guidelines but also because enforcement policy had drifted far from the standards articulated in the previous Guidelines. The 2010 Guidelines are distinctive manly for two things. One is briefer and less detailed treatment of market delineation. The other is an expanded set of theories of harm that justify preventing mergers or reversing mergers that have already occurred. The 2010 Guidelines reflect a growing belief that in markets where product differentiation is minimal competition tends to be robust and the structural presumptions stated in previous Guidelines were too harsh. By contrast, where product differentiation is substantial the Guidelines?? approach tended to define markets too broadly, overlooking significantly anticompetitive possibilities. Under the 2010 Guidelines unilateral effects analysis relevant markets can be very small, often limited to three or four firms, and excluding some obvious substitutes. Markets in merger analysis are not defined for their own sake, however, but rather to ascertain whether a particular alteration in market structure covered by the merger provisions will be likely to facilitate a price increase. The 2010 Guidelines address four substantive merger concerns: exclusion, restraints on innovation, unilateral effects, and coordinated effects. The Guidelines have a separate section on mergers limiting ??innovation and product variety,?? treated mainly in the category of unilateral effects. The 2010 Guidelines are more flexible than previous Guidelines and also more catholic about the types of harms that mergers might cause and the techniques that can be used to assess them. Older Guidelines were excessively wed to methodologies that were at the forefront of applied merger analysis when they were drafted, but that tended to make the Guidelines obsolete as new methodologies became available. Not only do methodologies change, they are also specific to the situation. Further, they tend to be well developed in the literature and accessible to experts consulted by those defending a merger as well as to the government economists who employ them. To be sure, there is a tradeoff between flexibility and guidance. Often we can have more of one only by giving up some of the other, and that tradeoff is clearly present in the 2010 Guidelines.  相似文献   
85.
It has been assumed that the associative process plays a central and important role in advertising creativity. Yet, although this assumption has long been recognized, we know very little, other than intuitively, about the creative process itself. This paper represents a preliminary inquiry into this gap of advertising theory, formulating an associative model for the individual copywriter's creative process. More specifically, this study examines the relationship of associative ability, attitude, and creative ability, as conceptualized in the presented model. The findings suggest a direct and significant relationship among these three variables.  相似文献   
86.
87.
88.
89.
90.
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