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81.
82.
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   
83.
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   
84.
This paper examines the role of media coverage and investor attention on the outcomes of seasoned equity offerings (SEOs). I use an archive of Thomson Reuters news articles to proxy for firm visibility and investor attention. I find that the volumes of news articles prior to the offerings are positively associated with the offer price discounts of SEOs. Furthermore, the volumes of news articles are negatively associated with the cumulative abnormal returns three days around the SEOs. I conclude that the costs of equity increase with media coverage prior to SEOs. Overall, the evidence is consistent with the hypothesis that media coverage affects investors' information processing in SEOs. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
85.
In this conceptual article, the authors propose a framework for how progressive human rights outcomes may be obtained in the context of bidding, planning and implementing major sport events (MSEs) through the implementation of four pathways, including good governance, the democratic participation of stakeholders, the formalisation of human rights agendas and the deployment of sensitive urban development. The authors argue that there is a need for adherence to internationally recognised standards, such as the Universal Declaration of Human Rights and the United Nations Guiding Principles on Business and Human Rights if rhetorical statements from MSE awarding bodies and host organisers are to be accountable to a wider set of actors. If researchers and practitioners want to address some of the critical issues related to human rights and MSEs, it is imperative that key actors working in the rights sphere are involved in shaping the research agenda and monitoring its implementation. Academics need to take a proactive approach aimed at achieving both theoretically grounded and practically relevant solutions, with engagement occurring over an extended period of time. This approach, avowedly political and concerned with genuine action, is a key way in which MSE stakeholders can be held to account for their actions in regard to human rights.  相似文献   
86.
A growing literature finds evidence that flood risk salience varies over time, spiking directly following a flood and then falling off individuals' cognitive radar in the following years. In this article, we provide new evidence of salience exploiting a hurricane cluster impacting Florida that was preceded and followed by periods of unusual calm. Utilizing residential property sales across the state from 2002 through 2012, our main estimate finds a salience impact of ?8%, on average. The salience effect persists when we base estimation only on spatial variation in prices to limit confounding from other simultaneous changes due to shifting hedonic equilibria over time. These effects range from housing prices decreases of 5.4–12.3% depending on the year of sale. Understanding flood risk salience has important implications for flood insurance and disaster policy, the benefits transfer literature, and, more broadly, our understanding of natural disaster resilience. JEL Classification: Q51, Q54, R21  相似文献   
87.
In this paper, we consider the feasibility of constructing online sentiment indices, using large amounts of media data, as an alternative to the conventional survey method used to create the consumer confidence index in South Africa. A clustering framework is adopted to provide an indication of possible candidate sentiment indices constructed from a combination of different text sources and dictionaries that best mimic the traditional survey-based consumer confidence index from the South African Bureau for Economic Research (BER). The results conclude that it is possible to create an index using sentiment analysis using online editorial data that does resemble the BER’s consumer confidence index. The different media-based sentiment indices (MSI) show a significant level of correlation and co-movement with the BER’s CCI. Impulse responses and cross-correlation functions indicate that the MSI could potentially lead the survey-based method up to two quarters. Furthermore, Granger-causality tests show that the media-based indices are good predictors of future consumer confidence index values. The results provide motivation for further study on the use of sentiment-based techniques and online media data sources to track consumer confidence within an emerging market such as South Africa.  相似文献   
88.
The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.  相似文献   
89.
Auditors frequently use valuation specialists to help them evaluate fair values, but researchers and regulators know little about how auditors use these specialists. Based on interviews with 28 auditors and 14 valuation specialists, I develop a theoretical framework informed by expert systems and professional competition theories. The interviews suggest that institutional pressures in the fair value environment unevenly impact auditors and specialists, causing tension between auditors' needs for ontological security and jurisdictional claims. This tension leads to one-sided competition between auditors and specialists and incomplete acceptance of specialists' work. Auditors' competitive behaviors coupled with this incomplete acceptance result in a tendency to make specialists' work conform to auditors' views. Collectively, these findings suggest that auditors use specialists as an institutional mechanism to create comfort, but not insight. This study links expert systems and professional competition theories, and it provides critical insight into some assumptions underlying tenets of each theory. It also informs researchers, regulators, and practitioners interested in understanding and addressing problems related to the use of specialists.  相似文献   
90.
Our purpose is to explore the concept of “sustainability” when understood from a performative perspective, i.e. as a concept that is filled with meaning across time. Drawing on a 10 year-long study of the digital footprint of Stockholm Royal Seaport, claimed to be northern Europe's largest sustainable urban development district, we show that “sustainability” emerged as the project became associated with particular places, projects, histories, and technologies. This means that “sustainability” was local in that it was situated in the particular spatial context of the project; temporal in that it was situated in a particular time; and political in that it expressed particular values and perspectives. The study contributes to explaining why “sustainability” remains—and always will remain—a contested concept, which is why sustainability transitions are complex. Consequently, we suggest that the transition towards sustainability always involves the transition of sustainability, something that needs to be acknowledged in order for a transition to actually become sustainable.  相似文献   
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