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   14926篇
  免费   331篇
财政金融   3219篇
工业经济   1161篇
计划管理   2337篇
经济学   3221篇
综合类   152篇
运输经济   106篇
旅游经济   224篇
贸易经济   2296篇
农业经济   645篇
经济概况   1882篇
信息产业经济   2篇
邮电经济   12篇
  2023年   84篇
  2021年   92篇
  2020年   203篇
  2019年   257篇
  2018年   337篇
  2017年   333篇
  2016年   310篇
  2015年   209篇
  2014年   329篇
  2013年   1604篇
  2012年   407篇
  2011年   500篇
  2010年   452篇
  2009年   461篇
  2008年   419篇
  2007年   374篇
  2006年   360篇
  2005年   281篇
  2004年   283篇
  2003年   273篇
  2002年   274篇
  2001年   278篇
  2000年   294篇
  1999年   298篇
  1998年   311篇
  1997年   282篇
  1996年   249篇
  1995年   231篇
  1994年   252篇
  1993年   271篇
  1992年   275篇
  1991年   271篇
  1990年   228篇
  1989年   203篇
  1988年   185篇
  1987年   181篇
  1986年   181篇
  1985年   252篇
  1984年   277篇
  1983年   261篇
  1982年   233篇
  1981年   226篇
  1980年   186篇
  1979年   190篇
  1978年   169篇
  1977年   144篇
  1976年   130篇
  1975年   156篇
  1974年   105篇
  1973年   101篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Integrating ecosystem services into conservation assessments: A review   总被引:8,自引:0,他引:8  
A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.  相似文献   
112.
Permit markets are celebrated as a policy instrument since they allow (i) firms to equalize marginal costs through trade and (ii) the regulator to distribute the burden in a politically desirable way. These two concerns, however, may conflict in a dynamic setting. Anticipating the regulator's future desire to give more permits to firms that appear to need them, firms purchase permits to signal their need. This raises the price above marginal costs and the market becomes inefficient. If the social cost of pollution is high and the government intervenes frequently in the market, the distortions are greater than the gains from trade and non-tradable permits are better. The analysis helps to understand permit markets and how they should be designed.  相似文献   
113.
In the debate on forecasting exchange rates, critics claimed that traditional macroeconomic models could not outperform a random walk in post‐sample forecasts. Perceived deficiencies include inadequate allowance for simultaneity, and expectations hypotheses inconsistent with the structure of models employed. This paper re‐visits the debate, first to address critics' major concerns, and second because in the view of the present authors, the debate closed on an unduly pessimistic note. This paper develops a simultaneous, rational expectations model of the USD/GBP market, with functional relationships for hedgers, speculators and a spot rate equation. The model is estimated with data contemporaneous to the debate, including a period during which the US Commodity Futures Trading Commission did not collect data on traders' open positions. Using the results of post‐debate research on tests for stationarity with missing observations, the model, using only public information, outperforms a random walk in post‐sample forecasts of the spot rate. Recent microstructure models of the exchange rate based on order flow have re‐kindled the forecasting debate. The model developed here, however, is differentiated from these microstructure models, first because order flow utilises both public and private information, and second because the microstructure models do not directly address critics' concerns.  相似文献   
114.
This paper examines how the relationships linking money to real output are altered when an international-domestic interest rate gap is included in the model. The results indicate that both the international-domestic interest rate gap and term structure exert a statistically significant effect on real economic activity. In addition, fluctuations in these variables contain significant information about future changes in real output. An interesting finding is that while the term structure dominates the international-domestic interest rate gap when estimating the entire time period, 1970:1–1996:4, the international-domestic interest rate gap clearly dominates in the more recent time period, 1985:1–1996:4.  相似文献   
115.
Let > be an interval order on a topological space X, and let x > 1 y if and only if there exists x′ with x?x′>y. Then >1 is a preference relation with transitive indifference, which, under suitable conditions, can be represented by a utility function v of the usual sort. In that case, maximisation of v (subject to contraints) leads to a most preferred point relative to >. Following both the Debreu-Rader and the Arrow-Hahn approaches, we discuss the existence and continuity of such a function v.  相似文献   
116.
117.
118.
We consider the design of ambient taxes forrisk-neutral and risk-averse polluters whenpolluters and the regulatory agency haveasymmetric information about environmentalrelationships and probabilities associatedwith random events. Unlike prior work, we showthat under these conditions, optimal ambienttaxes must be firm-specific, and accompaniedby additional incentives to influencepolluters' choices of abatement techniques.  相似文献   
119.
We explore international variation in business cycle dynamics to gain insights into the recent pattern of robust productivity growth during downturns (productive recessions) and weak employment growth during recoveries (jobless recoveries) seen in some advanced economies. We find that sectoral change is associated with productive recessions but that labor market rigidity can impede reallocation and reduce the probability of a productive recession. We also find evidence of a link between productive recessions and jobless recoveries and that recessions dominated by reductions to employment, rather than changes in average employee hours, are more likely to be associated with jobless recoveries. (JELF44, E32)  相似文献   
120.
ABSTRACT * : The author highlights the problems and prospects of public enterprises within the European Union, as well as the major adjustments considered necessary for these enterprises to fulfil their role. He argues that general criteria determining whether the production of goods and services should be in the public sector cannot be readily established in the European Union, since public supply does not solely depend on the specific economic characteristics of the particular good or service, but also on the prevailing social, cultural and economic conditions in each country, on the economic policy pursued, and on the structural characteristics of its private and public sectors, including entrepreneurial and trade union behaviour.  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