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   20893篇
  免费   1308篇
  国内免费   763篇
财政金融   1444篇
工业经济   688篇
计划管理   4578篇
经济学   1585篇
综合类   1688篇
运输经济   183篇
旅游经济   173篇
贸易经济   1958篇
农业经济   739篇
经济概况   1010篇
水利工程   8918篇
  2024年   70篇
  2023年   264篇
  2022年   323篇
  2021年   511篇
  2020年   509篇
  2019年   455篇
  2018年   422篇
  2017年   527篇
  2016年   646篇
  2015年   745篇
  2014年   1447篇
  2013年   1566篇
  2012年   1553篇
  2011年   1871篇
  2010年   1451篇
  2009年   1185篇
  2008年   1338篇
  2007年   1363篇
  2006年   1271篇
  2005年   1205篇
  2004年   942篇
  2003年   791篇
  2002年   577篇
  2001年   430篇
  2000年   400篇
  1999年   255篇
  1998年   198篇
  1997年   130篇
  1996年   137篇
  1995年   99篇
  1994年   100篇
  1993年   52篇
  1992年   39篇
  1991年   24篇
  1990年   10篇
  1989年   14篇
  1988年   3篇
  1987年   7篇
  1986年   6篇
  1985年   5篇
  1984年   8篇
  1983年   13篇
  1982年   1篇
  1981年   1篇
排序方式: 共有10000条查询结果,搜索用时 708 毫秒
1.
2.
We exploit an influential 1991 Delaware court ruling to examine simultaneously two types of conservatism that play important roles in resolving creditor–owner agency conflicts: contracting conservatism and reporting conservatism. The ruling expanded managerial fiduciary duties in favor of creditors for Delaware-incorporated firms in the vicinity of insolvency. In those firms, following the ruling, debt contracts are less likely to include conservative adjustments to accounting numbers used for covenant compliance (i.e., contracting conservatism decreases), while public financial reporting becomes more conservative (i.e., reporting conservatism increases). The decrease in contracting conservatism is concentrated in firms that exhibit a greater increase in reporting conservatism, suggesting that reporting conservatism is more cost-effective in resolving agency conflicts. In addition, the substitution effect is more pronounced in firms facing greater business uncertainty and firms with greater board independence.  相似文献   
3.
Due to the paucity of sources of negative firm‐specific information, US capital markets have more difficulty identifying and incorporating bad news into stock prices than they do good news. Even though insider selling is a potentially important proxy for undisclosed bad news, researchers have difficulty ex ante identifying information‐based sales due to an inability to separate liquidity‐motivated from information‐based insider trades. We hypothesize that when insiders in multiple firms sell shares of one firm in which they are insiders and at the same time buy shares of other insider portfolio firms, the sale is more likely to be information‐based, since the proceeds are reinvested. Conversely, when an insider sells one firm without purchasing others or sells multiple insider firms the sale is likely liquidity‐motivated. We find that insider sales identified as information‐based using this algorithm are followed by significant negative abnormal returns. Information‐based sales are also more likely to be associated with delistings, earnings declines and earnings restatements. Analysts are also more likely to revise their earnings forecasts downwards for these firms. It is thus possible to ex ante identify insider sales with information content. Our results will be of interest to investors and also to regulators designing insider trading rules.  相似文献   
4.
《Business Horizons》2019,62(4):539-548
The U.S. healthcare sector is inadequately prepared to deal with the reality of cyber threats. The increasing use of smart medical equipment and mobile devices is making healthcare organizations more susceptible to ransomware and other types of malware. The size and complexity of operations, coupled with the presence of numerous legacy and incompatible systems, make it difficult to implement effective cybersecurity measures. The daunting nature of the problem often results in an if-it-ain’t-broke-don’t-fix-it stance among senior healthcare leaders. The preponderance of healthcare-related laws, compliance regulations, and security guidance frameworks serve to complicate the cybersecurity challenge further and too often results in senior leadership assuming a state of blissful ignorance. This study sheds light on the key factors contributing to the chaotic state of affairs and presents a roadmap to a more deliberate and proactive approach to cybersecurity risk management.  相似文献   
5.
We commemorate the 50th anniversary of Ball and Brown [1968] by chronicling its impact on capital market research in accounting. We trace the evolution of various research paths that post–Ball and Brown [1968] researchers took as they sought to build on the foundation laid by Ball and Brown [1968] to create a body of research on the usefulness, timeliness, and other properties of accounting numbers. We discuss how those paths often link back to the groundwork laid and questions originally posed in Ball and Brown [1968].  相似文献   
6.
The present study investigates a potential preventive factor in relation to workplace bullying. Specifically, we examine how climate for conflict management (CCM) may be related to less bullying, increased work engagement, as well as whether CCM is a moderator in the bullying engagement relationship. The study was based on a cross-sectional survey among employees in a transport company (N = 312). Hypotheses were tested simultaneously in a moderated mediation analysis which showed that bullying and job engagement were related (H1), CCM was related to less reports of bullying (H2), CCM was related to work engagement (H3) and that CCM was indirectly related to job engagement through bullying (H4), but only when CCM was weak (H5). That is, CCM moderated the relationship between bullying and work engagement in that this relationship only existed when CCM was low. The present study contributes to theory within this research field by showing that organizational measures may not only prevent bullying, but may also affect how employees react when subjected to bullying. Furthermore, the effect of climate in relation to bullying may be down to the narrow bandwidth facet of CCM. The study informs employers how they may act to prevent bullying while also reducing the potential negative outcomes of those cases of bullying that inevitably will show up from time to time.  相似文献   
7.
Many food regulations focus on test/measurement indicators, such as hazard analysis and critical control points (HACCP) and traceability, etc. Other than these indicators, the food industry uses various cues such as product origin as indicators of product quality. However, in an environment where consumers’ confidence in food safety is low due to frequent food safety scandals, little is known about the efficiency of these test/measurement indicators and cues. This paper used the primary data collected in Zhengzhou (China) to estimate consumers’ preferences for test/measurement indicators and a new cue of “own farm” for milk powder. Our results show that country of origin is the most important cue attribute, followed by price and own farm. The importance of test/measurement indicators such as organic, traceability, and HACCP certification is relatively low. Also, the individual parameter estimates show that consumers’ preferences for test/measurement indicators currently in the market are weak and fragile. Interestingly, price has an inverse-U-shaped relationship with consumer utility, implying that Chinese consumers may perceive low-price milk powder as low quality. The results of this study provide important insight for regulatory authorities and the food industry to develop more effective policies and programs to improve consumer preferences for milk powder.  相似文献   
8.
西藏江达县白格村金沙江右岸于2018年10月11日和2018年11月3日先后发生2次大规模滑坡—堰塞湖堵江事件,溃堰洪水对下游拉哇库区不良地质体的稳定性造成不同程度的影响。为保障下游水电站建设安全,对拉哇库区主要不良地质体建立了基于星载InSAR技术、无人机技术和地面传感器实时监测的“天空地”一体化监测预警体系,以多维空间采集技术获取变形信息,通过智能监控平台对信息及时进行处理、分析和可视化呈现,利用平台、短信等方式向相关人员进行分级告警,取得了较好的应用效果。  相似文献   
9.
10.
We comprehensively analyze the predictive power of several option-implied variables for monthly S&P 500 excess returns and realized variance. The correlation risk premium (CRP) and the variance risk premium (VRP) emerge as strong predictors of both excess returns and realized variance. This is true both in- and out-of-sample. Our results also reveal that statistical evidence of predictability does not necessarily lead to economic gains. However, a timing strategy based on the CRP leads to utility gains of more than 5.03% per annum. Forecast combinations provide stable forecasts for both excess returns and realized variance, and add economic value.  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