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845.
This paper investigates whether governments can change market structures through interventions. We study the effects of four political events over the life cycle of the market for daily newspapers in the Netherlands. We find that policy measures meant to lower entry barriers in an expanding industry created new entry and increased survival chances for potential entrants and incumbent newspapers. Exit barrier enhancing policies to reduce concentration tendencies have not been successful.  相似文献   
846.
Lejeune  Miguel A. 《NETNOMICS》2002,4(2):145-162
Denial of Service (DoS) attacks consist of overwhelming a server, a network or a Web site in order to paralyze its normal activity. The additional parameter in Distributed Denial of Service (DdoS) attacks is the distributing strategy. It means that DDoS attacks do not come from a single computer but stem from all accessible channels and servers. Consequences are multiple, ranging from system errors, temporary inability to access the Web site for normal users to challenging the actual reliability of the Internet. Despite this, Internet users show carelessness. The explanation lies in the specificities of DDoS attacks. We explore possibilities to raise users' awareness about the actual amplitude of problems caused by DDoS attacks. We suggest a careful examination of Internet pricing mechanisms and switching from flat to usage-constraining pricing schemes.  相似文献   
847.
The use of transferable discharge permits as a water pollution control policy is rapidly increasing in the United States. Drawing on evidence from existing water quality trading programs, this paper provides a taxonomy of the forms that such markets take. Four main structures are identified: exchanges, bilateral negotiations, clearinghouses, and sole-source offsets. Each of these structures has its own strengths and weaknesses; none is optimal for all scenarios. Since market structure is largely determined by a program's rules, policy makers should be aware of the differences between these structures and the conditions under which each comes to be.  相似文献   
848.
Agricultural policy reform has been an important source of change in the Chinese agricultural sector. The reforms led to productivity growth and helped China to pursue its self-sufficiency goal especially in the grain sector. In order to analyze whether observable productivity growth stems from technologically induced components or from the market induced parts, a multi-input–multi-output model is derived by using an econometric distance function framework. A decomposition allows to distinguish allocative effects, scale effects, technological change, and technical efficiency change. Data on farms in Zhejiang from 1986 to 2000 are used to analyze the impact of policy reform.  相似文献   
849.
Elicitation using multiple price list formats   总被引:2,自引:0,他引:2  
We examine the properties of a popular method for eliciting choices and values from experimental subjects, the multiple price list format. The main advantage of this format is that it is relatively transparent to subjects and provides simple incentives for truthful revelation. The main disadvantages are that it only elicits interval responses, and could be susceptible to framing effects. We consider extensions to address and evaluate these concerns. We conclude that although there are framing effects, they can be controlled for with a design that allows for them. We also find that the elicitation of risk attitudes is sensitive to procedures, subject pools, and the format of the multiple price list table, but that the qualitative findings that participants are generally risk averse is robust. The elicitation of discount rates appear less sensitive to details of the experimental design. Electronic Supplementary Material Supplementary material is available in the online version of this article at . JEL Classification C9, D81, D91 An erratum to this article is available at .  相似文献   
850.
There is ongoing debate about the apparent weak or negative relation between risk (conditional variance) and expected returns in the aggregate stock market. We develop and estimate an empirical model based on the intertemporal capital asset pricing model (ICAPM) that separately identifies the two components of expected returns, namely, the risk component and the component due to the desire to hedge changes in investment opportunities. The estimated coefficient of relative risk aversion is positive, statistically significant, and reasonable in magnitude. However, expected returns are driven primarily by the hedge component. The omission of this component is partly responsible for the existing contradictory results.  相似文献   
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