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991.
The doctrine regarding unforeseeable damages in a contract was established in the well known case of Hadley vs. Baxendale. According to the judgement, a plaintiff cannot be compensated for unforeseeable damages in an incomplete contract unless he informs the defendant of the possible unforeseen contingency beforehand. In this paper, I extend the argument to the tort case in which it is hardly possible to communicate between a plaintiff and a defendant before an accident occurs. In the case of the sequential bilateral accident in which the victim’s care level is observable to the injurer, the victim’s care level can be a signal of the unforeseen contingency. I mainly discuss the implementability of the social optimum by the contributory negligence with dual standard of care enabling the communication between the parties.  相似文献   
992.
993.
Moore's Law has created a popular perception of exponential progress in information technology. But is the progress of IT really exponential? In this paper we examine long time series of data documenting progress in information technology gathered by [1]. We analyze six different historical trends of progress for several technologies grouped into the following three functional tasks: information storage, information transportation (bandwidth), and information transformation (speed of computation). Five of the six datasets extend back to the nineteenth century. We perform statistical analyses and show that in all six cases one can reject the exponential hypothesis at statistically significant levels. In contrast, one cannot reject the hypothesis of superexponential growth with decreasing doubling times. This raises questions about whether past trends in the improvement of information technology are sustainable.  相似文献   
994.
There exist few quantitative assessments of the relationship between biodiversity per se and economic benefits at scales that are relevant for conservation. Similarly, the merits of Community-Based Natural Resource Management programs for both wildlife and people are contested. Here, we harness two databases, on wildlife surveys and financial benefits, to address these issues for communal conservancies in northwest Namibia. We use ordination methods to characterize the diversity and stability of large wildlife assemblages on conservancies, and demonstrate that diversity (but not stability) is an important explanator of conservancy financial benefits. Our results indicate that for this area of Namibia, biodiversity, as represented by large wildlife assemblages, has an important, positive effect on the tangible financial benefits that people derive from conservation programs.  相似文献   
995.
The marked increase in the availability of spatial data has forced researchers engaged in land use modeling to directly confront the question of space and the theoretical and methodological challenges involved in developing spatial models. Advances have come from multiple disciplines, most notably through the development and application of spatial theory and methods from regional science, geography, urban economics and more recently, theoretical and applied econometrics. The main goal of this paper is to summarize the econometric challenges of spatial data and to highlight spatial models and methods with a particular focus on models of land markets and land use change. We also discuss the data and modeling challenges associated with modeling the underlying spatial economic mechanisms that give rise to land use patterns and the complexities involved in modeling land use as a coupled economic-ecological system.  相似文献   
996.
The Baltimore Gas and Electric Company (BGE) undertook a dynamic pricing experiment to test customer price responsiveness to different dynamic pricing options. The pilot ran during the summers of 2008 and 2009 and was called the Smart Energy Pricing (SEP) Pilot. In 2008, it tested two types of dynamic pricing tariffs: critical peak pricing (CPP) and peak time rebate (PTR) tariffs. About a thousand customers were randomly placed on these tariffs and some of them were paired with one of two enabling technologies, a device known as the Energy Orb and a switch for cycling central air conditioners. The usage of a randomly chosen control group of customers was also monitored during the same time period. In 2009, BGE repeated the pilot program with the same customers who participated in the 2008 pilot, but this time it only tested the PTR tariff. In this paper, we estimate a constant elasticity of substitution (CES) model on the SEP pilot’s hourly consumption, pricing and weather data. We derive substitution and daily price elasticities and predictive equations for estimating the magnitude of demand response under a variety of dynamic prices. We also test for the persistence of impacts across the two summers. In addition, we report average peak demand reduction for each of the treatment cells in the SEP pilot and compare the findings with those reported from earlier pilots. These results show conclusively that it is possible to incentivize customers to reduce their peak period loads using price signals. More importantly, these reductions do not wear off when the pricing plans are implemented over two consecutive summers. Our analyses reveal that SEP participants reduced their peak usages in the range of 18 to 33% in the first summer of the SEP pilot and continued these reductions in the second summer.  相似文献   
997.
Invasive animal pests reduce crop and livestock output, require management and control measures, and threaten native plants, animals and their habitat. The agricultural and management costs are often directly measurable. But the costs to protect threatened native plants and animals are harder to assess. The Rural Lands Protection Boards were the government agency in New South Wales that managed invasive animals. An analysis of their decisions provided the opportunity to estimate the costs of protecting native species. The number of native plants and animals threatened by invasive pests was modelled against the expenditure, area, pest abundance, climate and location of 38 Board districts. There was a strong negative relationship between the number of threatened native species and Board expenditure. This relationship was interpreted to estimate the marginal cost of protecting a threatened native species, the downward shift in the supply curve necessary to protect all threatened native species, and the gains from the shift in the form of cost savings in the continued protection of non-threatened native species. These results value some of the costs that invasive animal pests impose on the environment.  相似文献   
998.
999.
This paper presents the first value of statistical life (VSL) meta-analysis that empirically estimates correction factors for ‘out of context’ benefits transfer (BT) purposes. In the field of mortality risk reductions elicited willingness to pay values in one risk context, say road safety, are frequently applied in other risk contexts like air pollution. However, differences in risk perception and the population at risk across contexts are likely to result in diverging VSL estimates. In a meta-analysis of 26 international stated preference studies, a Bayesian model is estimated regressing contingent values for mortality risk reductions, originating from three different risk contexts, on the characteristics of the risk reduction itself and additional variables characterizing the underlying studies. A willingness to pay (WTP) premium for mortality risk reductions in the air pollution and general mortality risk context relative to improving road safety is observed. Evaluated at the mean, road safety VSL estimates should be multiplied by a factor 1.8 before being applicable in the air pollution context. Moreover, in an illustrative BT exercise we find limited overlap in the set of context specific predictive VSL distributions. Consequently, ‘out of context’ BT results in a substantial over- or underestimation of the VSL.  相似文献   
1000.
Public disclosure programs that collect and disseminate information about firms’ environmental performance are increasingly popular in both developed and developing countries. Yet little is known about whether they actually improve environmental performance, particularly in the latter setting. We use detailed plant-level survey data to evaluate the impact of India’s Green Rating Project (GRP) on the environmental performance of the country’s largest pulp and paper plants. We find that the GRP drove significant reductions in pollution loadings among dirty plants but not among cleaner ones. This result comports with statistical and anecdotal evaluations of similar disclosure programs. We also find that plants located in wealthier communities were more responsive to GRP ratings, as were single-plant firms.  相似文献   
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