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   27745篇
  免费   257篇
财政金融   4619篇
工业经济   1659篇
计划管理   4435篇
经济学   6234篇
综合类   586篇
运输经济   98篇
旅游经济   210篇
贸易经济   6213篇
农业经济   535篇
经济概况   2784篇
信息产业经济   46篇
邮电经济   583篇
  2021年   85篇
  2020年   141篇
  2019年   210篇
  2018年   2571篇
  2017年   2360篇
  2016年   1532篇
  2015年   250篇
  2014年   357篇
  2013年   1161篇
  2012年   781篇
  2011年   2356篇
  2010年   2131篇
  2009年   1857篇
  2008年   1835篇
  2007年   2163篇
  2006年   340篇
  2005年   609篇
  2004年   694篇
  2003年   831篇
  2002年   513篇
  2001年   289篇
  2000年   306篇
  1999年   222篇
  1998年   245篇
  1997年   212篇
  1996年   230篇
  1995年   174篇
  1994年   163篇
  1993年   184篇
  1992年   189篇
  1991年   182篇
  1990年   180篇
  1989年   130篇
  1988年   112篇
  1987年   115篇
  1986年   147篇
  1985年   194篇
  1984年   151篇
  1983年   138篇
  1982年   116篇
  1981年   138篇
  1980年   115篇
  1979年   124篇
  1978年   126篇
  1977年   73篇
  1976年   90篇
  1975年   68篇
  1974年   61篇
  1973年   68篇
  1972年   60篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
In this article the impact of technology education, as a new learning area (subject) in the curriculum, on in-service teacher education in South Africa is described in order to ascertain the extent of the impact. The research on which this article is based draws on a variety of experiences and observations in the field at grassroots level (in particular an outreach project in rural communities). The envisaged impact of technology education on South African schools, communities, teacher educators and teachers, the range of in-service teacher education that is required, and the impacts in urban and rural areas are discussed. Finally a number of concluding remarks are made about the extent of the impact of the inclusion of technology education in the new National Curriculum Statement and whether the situation has changed since the implementation of a pilot technology education project in 1998. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
12.
The paper extends Manning's model on education and balanced growth to include labour immigration. Each immigration unit is assumed to consist of one skilled worker and some unskilled members. The optimal immigration policy which maximizes the per capita steady-state consumption of the host country is derived. We show that optimal immigration policy can reduce the steady-state skilled labour ratio. More interesting still, contrary to the widespread belief that immigration of skilled workers hurts local skilled workers, it is the unskilled local workers whose interests are threatened by optimal immigration policy.  相似文献   
13.
14.

The paper deals with effects of price changes on measurement of poverty. It is shown that there are situations, when prices and nominal incomes change, a higher nutritional intake or an increase in commodity consumption of the poor can be associated with higher poverty gaps and a higher poverty index of the society. A positive relationship of this kind is quite counter-intuitive in the context of poverty measurement. This is caused by the adjustment of the poverty line and/or incomes of one situation by the prices of the other for the purpose of comparison.

  相似文献   
15.
This study examines whether the uncertainty arising from a firm's exposure to future environmental costs (environmental uncertainty) affects the market's price sensitivity to reported earnings. Specifically, when environmental uncertainty is significantly high, are investors more responsive to reported earnings released by 'high-polluting' firms than reported earnings announced by 'low-polluting' firms within the same industry? The initial impact of Title IV (the acid rain provisions) of the 1990 Clean Air Act Amendments (1990 CAAA) on the US electric utility industry provides the research setting required to isolate the effects of environmental uncertainty while addressing this question. Consistent with theoretical predictions, we find that the earnings response coefficients (ERCs) of high-polluting electric utilities are significantly greater than those of their low-polluting counterparts during a predicted period of elevated environmental uncertainty. In adjoining sample years associated with lower environmental uncertainty, we observe no statistical difference in the magnitude of the ERCs between these two groups. In addition, the study's findings suggest that the magnitude of the ERC is increasing in the firm's exposure to future environmental costs, after controlling for other factors that potentially affect ERCs.  相似文献   
16.
That survey research is error prone is not a new idea and different varieties of non-sampling error have been investigated in the literature as well as consideration being given in many statistics textbooks to the issue of sampling error. The paper here considers research upon corporate environmental reporting. It compares information provided by corporate environmental reports with information that survey respondents claim their organization’s environmental report contains. This enables the accuracy of the claims to be assessed. Consideration is given to two different industries the Water industry and the Energy industry. Errors due to inaccurate reporting by survey respondents are shown to be relatively infrequent and respondents appear just about as likely to claim they report information that they do not, in fact, report as to fail to indicate that they report information that is, in fact, actually reported.  相似文献   
17.
We examine whether the use of the three‐moment capital asset pricing model can account for liquidity risk. We also make a comparative analysis of a four‐factor model based on Fama–French and Pástor–Stambaugh factors versus a model based solely on stock characteristics. Our findings suggest that neither of the models captures the liquidity premium nor do stock characteristics serve as proxies for liquidity. We also find that sensitivities of stock return to fluctuations in market liquidity do not subsume the effect of characteristic liquidity. Furthermore, our empirical findings are robust to differences in market microstructure or trading protocols between NYSE/AMEX and NASDAQ.  相似文献   
18.
19.
This article specifies what an optimal pollution tax should be when dealing with a vertical Cournot oligopoly. Polluting firms sell final goods to consumers and outsource their abatement activities to an environment industry. It is assumed that both markets are imperfectly competitive. Thus, the tax is a single instrument used to regulate three sorts of distortions, one negative externality and two restrictions in production. Consequently, the optimal tax rate is the result of a trade-off that depends on the firms’ market power along the vertical structure. A detailed analysis of Cournot-Nash equilibria in both markets is also performed. In this context, the efficiency of abatement activities plays a key-role. It gives a new understanding to the necessary conditions for the emergence of an eco-industrial sector.   相似文献   
20.
Summary  Competition authorities are increasingly measuring the effects of their enforcement actions, seeking a robust justification for the proliferation of competition policy. We highlight the importance of identifying the right counterfactual against which to measure effects, and set out the relevant categories of costs and benefits. We then explore how a balance can be struck between the benefits and inherent limitations of these measurement exercises. Relatively crude analyses of cartel action benefits can be sufficient to achieve public legitimacy for competition policy. Assessing the effects of merger and conduct inquiries is often ambiguous, but could be used to improve decision-making processes. Director and Managing Consultant, respectively, at Oxera, Oxford and London. The valuable comments of Fod Barnes, Kerry Hughes and an anonymous referee are gratefully acknowledged. The opinions expressed in this article are those of the authors alone.  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