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   13861篇
  免费   373篇
财政金融   2524篇
工业经济   1057篇
计划管理   2383篇
经济学   3264篇
综合类   175篇
运输经济   121篇
旅游经济   240篇
贸易经济   2054篇
农业经济   602篇
经济概况   1755篇
信息产业经济   2篇
邮电经济   57篇
  2021年   70篇
  2020年   150篇
  2019年   236篇
  2018年   254篇
  2017年   317篇
  2016年   284篇
  2015年   181篇
  2014年   317篇
  2013年   1376篇
  2012年   385篇
  2011年   434篇
  2010年   347篇
  2009年   459篇
  2008年   400篇
  2007年   343篇
  2006年   317篇
  2005年   302篇
  2004年   294篇
  2003年   330篇
  2002年   284篇
  2001年   285篇
  2000年   309篇
  1999年   290篇
  1998年   273篇
  1997年   281篇
  1996年   248篇
  1995年   234篇
  1994年   216篇
  1993年   224篇
  1992年   233篇
  1991年   234篇
  1990年   241篇
  1989年   200篇
  1988年   186篇
  1987年   185篇
  1986年   201篇
  1985年   256篇
  1984年   227篇
  1983年   214篇
  1982年   216篇
  1981年   208篇
  1980年   195篇
  1979年   211篇
  1978年   171篇
  1977年   157篇
  1976年   145篇
  1975年   104篇
  1974年   112篇
  1973年   113篇
  1972年   77篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Control groups can provide counterfactual evidence for assessing the impact of an event or policy change on a target variable. We argue that fitting a multivariate time series model offers potential gains over a direct comparison between the target and a weighted average of controls. More importantly, it highlights the assumptions underlying methods such as difference in differences and synthetic control, suggesting ways to test these assumptions. Gains from simple and transparent time series models are analysed using examples from the literature, including the California smoking law of 1989 and German reunification. We argue that selecting controls using a time series strategy is preferable to existing data‐driven regression methods.  相似文献   
2.
This paper presents an approach to assessing the efficacy of public spending on research and development in state programs. At present, there is a need to develop a unified approach to the analysis and evaluation of the efficacy of such spending from the perspective of participants in state programs (federal executive bodies). The proposed approach does not allow evaluating the efficacy of public spending on the development of research areas assigned to the authors.  相似文献   
3.
Differences in accrued gains and investors’ tax-sensitivity induce variation in a capital gains lock-in effect across mutual funds even for the same stock at the same time. Exploiting this variation, we show this effect influences funds’ governance decisions: higher capital gains decrease the likelihood a fund exits prior to contentious votes and increase the likelihood a fund votes against management. Consistent with tax motivation, these findings are concentrated among funds with tax-sensitive investors. Further, high aggregate capital gains across funds holding a stock predict a higher likelihood management loses a vote and a lower likelihood a contentious vote is proposed.  相似文献   
4.
Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming.  相似文献   
5.
President Biden was sworn in on January 20, 2021 after a 4‐year term by President Trump. Certainly, Trump's norm breaking presidency impacted Canada in significant ways and the agricultural sector was no exception. In this issue, we have a set of four short articles discussing the possible implications on Canadian agriculture of transitioning from a Trump to Biden presidency. Issues related to Canada‐U.S. agricultural trade, political norms and uncertainty, U.S. domestic support, participation in trade agreements, and U.S.‐China relations are all considered.  相似文献   
6.
Most development projects encounter a highly uncertain entitlement process that is largely uncontrollable by developers. In this study, entitlement is modeled as a separate stage within a compound real option, where developers begin with minimal control (maximum risk) and each successful stage increases control (decreases risk). We solve the model analytically, provide three‐dimensional numerical comparisons, and empirically test the model's predictions using hand collected rezoning petitions. Our main result refines the classic development option model: developers first invest early (secure entitlements) in order to obtain the option to subsequently delay investment (construct the optimal building at the optimal time).  相似文献   
7.
Despite the importance of good collaborative relationships in interorganisational projects, clients and contractors often develop adversarial relationships due to perceptual distance about key project issues. In this case study research, we investigated how perceptual distance emerges and changes over time, and how the collaborative relationship between client and contractor develops alongside these dynamics. In this exploration, we built upon agency theory and stewardship theory as complementary perspectives for understanding client-contractor collaborative relationships. We gathered quantitative and qualitative data in two projects, conducting three assessments in about one year. We found that perceptual distance increased and decreased over time, and that a reduction was typically associated with the collaborative relationship being characterized by stewardship rather than agency. These findings suggest that a regular assessment and evaluation of partners’ perceptions of critical project issues is warranted to timely detect and counteract perceptual distance. Moreover, partners would best adopt a stewardship orientation to reduce perceptual distance, although this may take considerable effort given the distributive nature of many pre-project negotiations.  相似文献   
8.
This study evaluates the impact of an automated reminder program designed to help credit counseling consumers manage their payment obligations and financial goals. Credit counseling consumers were randomly assigned to receive reminders linked to their financial goals and payment obligations for one year after an initial credit counseling session. We find that consumers offered reminders were 21% less likely than the control to experience severe (60+ day) payment delinquencies and were 12% less likely to experience a 30+ day delinquency. At the same time, these consumers saw a 10.5 point increase in credit scores relative to the control group. There were no significant impacts on total credit card balances or installment debt levels. This analysis provides promising evidence that automated reminders can provide an important complement to traditional credit counseling when it comes to improving consumers' credit profiles and does so at a fairly low cost.  相似文献   
9.
Demand for disclosures on environmental, social, and governance (ESG) issues has increased dramatically. Using corporate political spending disclosures as our setting, we conduct a detailed inquiry of 541 political spending‐related shareholder proposals from 2004 to 2012 to highlight the role of shareholder activism as a mechanism to motivate ESG disclosure. Unlike earlier studies, we examine both proposals that went to a vote and proposals that were withdrawn by the activist, allowing us to assess more comprehensively the success of shareholder activism. We find that 20 percent of firms targeted by disclosure proposals begin disclosing in the subsequent year, although implementation rates vary by proposal type—8 percent for proposals subject to a vote versus 56 percent for proposals withdrawn. The sponsor is also important: unions and public pension funds are less likely than other activists to target firms with agency problems and are less successful in having proposals withdrawn, and the implementations they obtain are viewed more negatively by the broader investor base. Our findings highlight shareholder proposals as one mechanism through which investors can successfully express their preferences for corporate disclosure policies. Given activists' long‐standing interest in environmental and social disclosure policies, we believe our findings generalize to a broader set of ESG disclosures.  相似文献   
10.
This paper is amongst the first to examine coopetition strategy for sustainable development at the network level. Companies who want to successfully implement complex innovative technologies that support sustainable development need to collaborate with other actors of the innovation ecosystem, including their competitors, so that they can develop standards, interoperable products, pool knowledge, and resources and bundle forces to compete against other technologies. Collaboration with competitors brings benefits, but also many risks. We investigated how firms cope with these risks when establishing an innovation ecosystem to implement a new technology in society. We conducted research in the Dutch smart grids sector and explored how these firms minimize inherent risks of coopetition. We found that system‐building actors in the Dutch smart grid field not only minimize inherent risks, but from the start of their collaboration they implement so‐called enablers to prevent these risks upfront.  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