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   372篇
  免费   14篇
财政金融   55篇
工业经济   24篇
计划管理   75篇
经济学   72篇
综合类   1篇
运输经济   5篇
旅游经济   8篇
贸易经济   104篇
农业经济   10篇
经济概况   23篇
邮电经济   9篇
  2023年   1篇
  2022年   3篇
  2021年   6篇
  2020年   13篇
  2019年   20篇
  2018年   22篇
  2017年   23篇
  2016年   24篇
  2015年   11篇
  2014年   22篇
  2013年   61篇
  2012年   15篇
  2011年   23篇
  2010年   18篇
  2009年   24篇
  2008年   10篇
  2007年   16篇
  2006年   8篇
  2005年   9篇
  2004年   4篇
  2003年   5篇
  2002年   7篇
  2001年   11篇
  2000年   2篇
  1999年   2篇
  1998年   3篇
  1997年   4篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   3篇
  1991年   4篇
  1990年   1篇
  1989年   4篇
  1987年   2篇
  1984年   1篇
  1967年   1篇
排序方式: 共有386条查询结果,搜索用时 15 毫秒
21.
The principal component regression (PCR) is often used to forecast macroeconomic variables when there are many predictors. In this letter, we argue that it makes sense to pre-whiten the predictors before including these in a PCR. With simulation experiments, we show that without such pre-whitening, spurious principal components can appear and that these can become spuriously significant in a PCR. With an illustration to annual inflation rates for five African countries, we show that non-spurious principal components can be genuinely relevant in empirical forecasting models.  相似文献   
22.
In this study, the association between information and communication technology (ICT) intensity in firms and labour productivity is explored across 14 European countries for the years 2001–2010. ICT intensity is approximated by the proportion of broadband internet-enabled employees, a novel indicator measuring not only adoption but also diffusion within and among firms. Data have been retrieved by means of the distributed microdata approach (DMD) from registers on business, trade and education as well as from surveys on production, ICT usage and innovation activities in firms held at the national statistical offices. This pioneering approach allows access to otherwise confidential linked firm-level information in dimensions not earlier available. Pooled OLS estimations based on approximately 400,000 observations in harmonised and representative datasets show that in a majority of countries there is a significant and positive relationship between the proportion of broadband internet-enabled employees and labour productivity in firms. However, the strength of the relationship varies across countries and industries. Manufacturing firms receive 50% larger estimates than the services firms, while the latter instead experience the positive association more frequently.  相似文献   
23.
We study a dynamic version of Meltzer and Richard's median‐voter model where agents differ in wealth. Taxes are proportional to income and are redistributed as equal lump‐sum transfers. Voting occurs every period and each consumer votes for the tax that maximizes his welfare. We characterize time‐consistent Markov‐perfect equilibria twofold. First, restricting utility classes, we show that the economy's aggregate state is mean and median wealth. Second, we derive the median‐voter's first‐order condition interpreting it as a tradeoff between distortions and net wealth transfers. Our method for solving the steady state relies on a polynomial expansion around the steady state.  相似文献   
24.
This paper aims to explore the link between creativity orientation, investment in visitors’ experience and operating and funding performance in tourist attractions, taking museums as a case study. The empirical work is based on an analysis of the information provided by a sample of Spanish, French, German, British and American museums. The findings highlight the positive impact of creativity orientation on museums’ operating performance, but show a curvilinear effect on funding performance. The use of new technologies and adaptation to the audience proves positive when seeking to attract visitors.  相似文献   
25.
This article investigates the relation between corporate governance mechanisms and dividend policy in Russian firms. Using a sample of Russian listed firms over the period 1998–2003, we estimate models for dividend pay probability and payout size. We find that there has been a significant increase in dividend payout levels which coincide with improvements in legal shareholder protection. State controlled firms are more frequent dividend payers as compared to other majority owned firms. We also find that dual share firms, in which corporate charters protect minority interests, have a higher dividend pay probability; while firms reporting according to US GAAP, which may be less likely to manipulate earnings, have a lower dividend payout.  相似文献   
26.
We use expert clinical and public health opinion to estimate likely changes in the prevention and treatment of important disease conditions and how they will affect future life expectancy. Focus groups were held including clinical and public health faculty with expertise in the six leading causes of death in the United States. Mortality rates and life tables for 2040 were derived by sex and age. Life expectancy at age 20 and 65 was compared to figures published by the Social Security Administration and to estimates from the Lee-Carter method. There was agreement among all three approaches that life expectancy at age 20 will increase by approximately one year per decade for females and males between now and 2040. According to the clinical experts, 70% of the improvement in life expectancy will occur in cardiovascular disease and cancer, while in the last 30 years most of the improvement has occurred in cardiovascular disease. Expert opinion suggests that most of the increase in life expectancy will be attributable to the already achieved reduction in smoking rates, especially for women.  相似文献   
27.
We propose a two-stage procedure to estimate conditional beta pricing models that allows for flexibility in the dynamics of asset betas and market prices of risk (MPR). First, conditional betas are estimated nonparametrically for each asset and period using the time-series of previous data. Then, time-varying MPR are estimated from the cross-section of returns and betas. We prove the consistency and asymptotic normality of the estimators. We also perform Monte Carlo simulations for the conditional version of the three-factor model of Fama and French (1993) and show that nonparametrically estimated betas outperform rolling betas under different specifications of beta dynamics. Using return data on the 25 size and book-to-market sorted portfolios, we find that the nonparametric procedure produces a better fit of the three-factor model to the data, less biased estimates of MPR and lower pricing errors than the Fama–MacBeth procedure with betas estimated under several alternative parametric specifications.  相似文献   
28.
We analyze the factors that drive exercise price policy for executive option plans (ESOPs) and their scope in a country where firms are not subject to the tax and accounting considerations that seem to have led to the dominance of at-the-money options in the US Our “unbounded” data for Finland provide us with an excellent opportunity to investigate whether contract design is consistent with compensation theory. Our findings are largely consistent with predictions from the optimal contracting literature. The size of the plan is negatively related to Tobin's Q and firm size and positively related to proxies for monitoring costs, which also influence the probability of launching premium ESOPs. Our results also show that the premium (out-of-the-moneyness) is negatively related to prior stock returns and cash flow-to-assets, which may be an indication of high-water mark contracting, or alternatively, of managerial power. Finally, we also find some support for a positive relation between the premium and the length of the vesting period when maturity is fixed, which indicates an effort to keep the incentives for management from falling over time.  相似文献   
29.
The present research examined the influence of different risk perspectives by the use of four different target persons (who could be affected: abstract person, self, specific person, and specific others) and of four different questionnaire answer formats (rating, open percentage, open, and closed frequency) on risk assessments. It was assumed that subjects use two different systems in terms of probabilistic reasoning: a distributional approach for abstract targets leading to higher risk estimates and a singular approach for specific targets leading to lower risk assessments. According to unrealistic optimism (UO) research (showing higher risk assessments for an abstract person than for self), the assumption was that risk assessments for a specific (named) target lead to lower risk assessments compared to an abstract target. Further, common quantitative answer formats for assessing risk were compared to explore differences in risk estimates. The hypotheses were tested using data of a sample of 512 students from a Bavarian university. The frequently confirmed finding of UO could be replicated with both rating scale and open frequency scale, which appeared to be more sensitive compared to the other used scales. However, UO disappeared when the comparison target was specific. Further, risk assessments for an abstract target were highest within every answer format and lowest for specific targets. Furthermore, results revealed that the type of answer format has a moderating effect on the extent of the influence of risk perspective on risk assessments. Overall, this study gives evidence that both the chosen scale and the risk perspective strongly influence risk assessments. Results aim to contribute to the research fields of quantitative assessment of perceived risk. They suggest that probabilistic reasoning in regard to risk not only underlies motivational or cognitive ego-defensive mechanisms but is rather presumably caused by the use of different systems of inferential strategies.  相似文献   
30.
Generalist primary school teachers often have little or no training in school subjects such as science and technology. Not surprisingly, several studies show that they often experience difficulties when teaching these subjects, in fact some primary teachers even avoid teaching them. The over all aim of this study is to contribute to new theoretical and methodological tools for the study of how teachers develop knowledge for teaching, i.e. pedagogical content knowledge (PCK). And based on this, elaborate on implications for the professional development of primary school teachers. The teachers in the study participated in a design-based research project concerning technology education in Grade 1. We were especially interested in whether the teachers displayed any habits that contributed to the development of their personal PCK. We found three significant patterns in how the teachers, together with the researcher, developed knowledge of how to teach a specific topic in technology. We argue that these patterns tell us something about the teachers’ epistemic habits in relation to the teaching of technology. The existence of these habits could help to explain how teachers with little or no experience of teaching a subject can develop relevant PCK.  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