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   16355篇
  免费   397篇
  国内免费   25篇
财政金融   2729篇
工业经济   1166篇
计划管理   2761篇
经济学   3345篇
综合类   590篇
运输经济   113篇
旅游经济   266篇
贸易经济   2385篇
农业经济   799篇
经济概况   2587篇
邮电经济   36篇
  2022年   108篇
  2021年   199篇
  2020年   234篇
  2019年   253篇
  2018年   260篇
  2017年   339篇
  2016年   296篇
  2015年   280篇
  2014年   421篇
  2013年   1380篇
  2012年   654篇
  2011年   774篇
  2010年   702篇
  2009年   557篇
  2008年   659篇
  2007年   609篇
  2006年   613篇
  2005年   516篇
  2004年   283篇
  2003年   296篇
  2002年   290篇
  2001年   288篇
  2000年   267篇
  1999年   271篇
  1998年   225篇
  1997年   203篇
  1996年   197篇
  1995年   184篇
  1994年   184篇
  1993年   211篇
  1992年   192篇
  1991年   192篇
  1990年   159篇
  1989年   172篇
  1988年   155篇
  1987年   143篇
  1986年   137篇
  1985年   251篇
  1984年   239篇
  1983年   217篇
  1982年   198篇
  1981年   190篇
  1980年   202篇
  1979年   196篇
  1978年   160篇
  1977年   175篇
  1976年   143篇
  1975年   134篇
  1974年   125篇
  1973年   128篇
排序方式: 共有10000条查询结果,搜索用时 572 毫秒
11.
12.
The historic precedents in telecommunications antitrust findings have tended towards finding harm to competition when network operators integrate downstream and bundle the provision of applications and services. The reason for this is that market power in network provision is thought to be extended into the applications market(s). More recently however, proposed mergers have been between telecommunications and media distribution firms, both of whom have some degree of market power, already sell their own services in bundles, and who may or may not have been offering combined bundles already via contractual agreements. Examples include Sky/Vodafone in New Zealand, and Time Warner/AT&T in the United States as well as Vodafone/Unitymedia in Germany and Media Capital/Altice in Portugal. These complex proposed arrangements pose challenges to competition authorities, whose legal and procedural rules and precedents, especially those defining the relevant markets affected by the merger or vertical integration activity, have been developed from the analysis of simpler cases. These precedents may not be sufficient to analyse current cases, characterized by multiple products catering to heterogeneous consumer preferences, and consumers are not constrained to buying only one variant of the products in each of the upstream and downstream markets.We illustrate the challenges by way of a case study of the proposed merger between Sky and Vodafone, declined by the New Zealand Commerce Commission in February 2017. Limitations in existing market definition processes and the evaluation of market power where bundling already occurs risk overlooking complex demand-side interactions that influence the profitability and efficiency of various structural and contractual strategic choices. We propose that classic merger and antitrust analysis based on econometric cost-benefit analysis can be augmented by using simulation and numerical analysis of a range of bundle offers expected to be relevant in decision-making. We develop a simple model and use it to illustrate how it may be used to inform broadband and content mergers, and other complex antitrust cases, such the assessment of the effects of two-sided markets and firm pricing decisions.  相似文献   
13.
Bio-economic modelling has become a useful tool for anticipating the outcomes of policies and technologies before their implementation. Advances in mathematical programming have made it possible to build more comprehensive models. In an overview of recent studies about bio-economic models applied to land-use problems in agriculture and forestry, we evaluated how aspects such as uncertainty, multiple objective functions, system dynamics and time have been incorporated into models. We found that single objective models were more frequently applied at the farm level, while multiple objective modelling has been applied to meet concerns at the landscape level. Among the objectives, social aspects are seldom represented in all models, when being compared to economic and environmental aspects. The integration of uncertainty is occasionally a topic, while stochastic approaches are more frequently applied than non-stochastic robust methods. Most multiple-objective models do not integrate uncertainty or sequential decision making. Static approaches continue to be more recurrent than truly dynamic models. Even though integrating multiple aspects may enhance our understanding of a system; it involves a tradeoff between complexity and robustness of the results obtained. Land-use models have to address this balance between complexity and robustness in order to evolve towards robust multiple-objective spatial optimization as a prerequisite to achieve sustainability goals.  相似文献   
14.
The Journal of Real Estate Finance and Economics - This paper provides new evidence on the effect of housing wealth on consumption by focusing on the impact of home-equity extraction. We develop a...  相似文献   
15.
16.
The Journal of Real Estate Finance and Economics - In the existing housing literature, there has been no academic consensus on how to combine the spatial dependence and the temporal dependence...  相似文献   
17.
Most studies on the predictability of moving average (MA) technical analysis use the discrete (buy/sell) trading recommendations. However, it is possibly incomplete or unreliable to explore the predictability of MA by only employing its generated trading signals. To further explore the forecastability of MA, we study its measurable impact on the stock market returns by using a conventional predictive regression framework. Our empirical study on the US stock market with respect to more detailed price information finds, (i) that the proposed predictor, MADP (MA based on daily prices) shows significant predictability in‐ and out‐of‐sample, and significantly outperforms the historical average (HA) benchmark as well as the MA based on monthly prices, (ii) that the predictability of MADP centers on the short‐term lags (within the most recent 10 days) and disappears when lags are beyond 20 days, and (iii) that the economic evaluation of the portfolios based on trading strategies confirms the superior performance of MADP with short‐term lags against the benchmark even though considering transaction costs.  相似文献   
18.
Using data for a sample of Malaysian stocks that are traded in both Malaysia and Singapore, we show that the turnover rate (trading volume relative to shares held) is significantly higher in the foreign market than in the domestic market. We also find that ownership of cross–listed shares by foreign investors is not motivated by diversification benefits. Instead, we find that the proportion of a firm's shares held in Singapore is directly related to the firm's level of systematic risk.  相似文献   
19.
Conventional urban economic analysis suggests that a local economy's size is closely related to a number of features, including levels of human capital and the availability of specialized inputs, which are likely to influence positively the rate at which it accumulates further economic activity. At the same time, urban theory also suggests that once cities reach a certain level of size, these agglomeration benefits begin to peter out, while diseconomies rise rapidly. Consequently, we should see an ‘inverted U‐shaped’ pattern of growth with respect to economic size—rates of growth first rise, then fall as size increases. This paper shows that, while such a pattern is largely absent from recent data on growth in metropolitan area population and employment, it emerges strikingly in county‐level data. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
20.
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