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981.
The implications of current trends in nanotechnology for the agri-food sector in India are assessed. Using published literature and patents data, a model to organize the information is developed through a specially designed database. The database allows mapping research themes in nanotechnology to specific sectors in the agricultural value chain to enable a rational assessment of the potential applications of nanotechnology in the agri-food sector, identifying and prioritizing research needs across the agricultural value chain, and assessing the environmental and societal implications of this emerging technology.  相似文献   
982.
983.
984.
This paper explores whether expert judgements can be taken as a proxy for citizen preferences for determining investment strategies for public goods. As an illustration, we focus on the provision of Public Rights Of Way (PROW) by Local Government Authorities in England. These provide rights of passage over property to those other than the owners, and little information is available on the welfare effects of changes in the provision and use of PROW. Given limited funds, reliance on expert judgement could be a cost effective alternative for decision-making compared with stated preference surveys of citizens. Two methods are compared. The Analytic Hierarchy Process (AHP) is used to elicit expert judgement to proxy citizen preferences for different attributes of PROW. The Choice Experiment (CE) technique is then used to derive preferences directly through personal interviews with citizens. Overall it was found that judicious use of AHP by experts can, in this instance, be used to represent citizen views. However, this result may not be easily generalisable to other settings.  相似文献   
985.
Open Source Software projects base their operation on a collaborative structure for knowledge exchange in the form of provision or reception of information, expertise and feedback on the creation of source code. Here, we address the direction of these knowledge flows among projects throughout social networks and their impact on project success. We identify the roles of membership or contribution that individuals play within projects. We found that connections through contributors who bring their knowledge to the project, improve project success, and that connection through members, who transfer their knowledge towards other projects, enhance project success. Finally, we found that ties through shared membership and contributions hamper project success. The analysis of knowledge flows and their impact on project success imply a translation of returns from investment in social capital, where investment takes the shape of knowledge flows and the returns mean the projects’ diffusion over the network.
Clara E. GarcíaEmail:
  相似文献   
986.
We consider the game in which b buyers each seek to purchase 1 unit of an indivisible good from s sellers, each of whom has k units to sell. The good is worth 0 to each seller and 1 to each buyer. Using the central limit theorem, and implicitly convergence to tied down Brownian motion, we find a closed form solution for the limiting Shapley value as s and b increase without bound. This asymptotic value depends upon the seller size k, the limiting ratio b/ks of buyers to items for sale, and the limiting ratio of the excess supply relative to the square root of the number of market participants. This work was sponsered in part by NSF Grant DMS-03-01795.  相似文献   
987.
988.
This article tests the public interest and regulatory capture hypotheses, in the context of the Swedish electricity market, by studying the factors influencing the Swedish Energy Agency’s decision to replace decision-makers it employs to hear customer complaints against utilities. The study covers the period from the beginning of 1996, when a series of regulatory reforms were introduced to improve consumer protection, until the end of 2008. The study concludes that decision-makers who find in favor of customers have had a statistically lower probability of being removed, consistent with public interest theory. A transitory effect of favoring utilities can be observed for the period from 2 to 6 years following the reforms. In this period, government and public scrutiny of the regulator, which had been high in the immediate aftermath of the reforms, had waned and there were few precedents decided by the courts that the regulator was required to follow. This vacuum created an opportunity for the utilities to increase their influence over the regulator. Once the courts started establishing precedents in relatively large numbers, the supervisory role of the courts ensured that the actions of the regulator were scrutinized. This development has served a similar function to government and public scrutiny in the years immediately following the reforms in promoting the public interest.  相似文献   
989.
Peter Leeson’s The Invisible Hook provides a readable and entertaining narrative of the hidden economics of the Golden Age of Piracy. This essay comments on one particular aspect of Leeson’s work: what we can learn from pirates about the emergence and evolution of property rights? I conclude that pirate codes had their origins in part in legally enforceable agreements and that pirates’ blend of individual and communal property rights bore some resemblance to the property rights of wandering tribal peoples.  相似文献   
990.
Real-world industries are composed from heterogeneous firms and substantial intra-industry reallocations take place, i.e. high productivity firms squeeze out low productivity firms. Previous tax-tool comparisons have not included these central forces of industry structure. This paper examines a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit taxes distort relative prices, which in turn reduces average industry productivity through reallocations (the survival and increased market share of lower productivity firms). Importantly, numerical solutions of the model reveal that the relative welfare loss from using the unit tax increases dramatically in the degree of firm heterogeneity.  相似文献   
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