88,022 research outputs found

    Uncertainty in Soft Temporal Constraint Problems:A General Framework and Controllability Algorithms forThe Fuzzy Case

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    In real-life temporal scenarios, uncertainty and preferences are often essential and coexisting aspects. We present a formalism where quantitative temporal constraints with both preferences and uncertainty can be defined. We show how three classical notions of controllability (that is, strong, weak, and dynamic), which have been developed for uncertain temporal problems, can be generalized to handle preferences as well. After defining this general framework, we focus on problems where preferences follow the fuzzy approach, and with properties that assure tractability. For such problems, we propose algorithms to check the presence of the controllability properties. In particular, we show that in such a setting dealing simultaneously with preferences and uncertainty does not increase the complexity of controllability testing. We also develop a dynamic execution algorithm, of polynomial complexity, that produces temporal plans under uncertainty that are optimal with respect to fuzzy preferences

    Towards Understanding Life Cycle Saving Of Boundedly Rational Agents: A Model With Feasibility Goals - Replaced by CentER Discussion Paper 2010-138

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    This paper develops a new life cycle model that aims to describe the savings and asset allocation decisions of boundedly rational agents. The paper’s main theoretical contribution is the provision of a simple, tractable and parsimonious framework within which agents make forward looking decisions in the absence of full contingent planning. Instead, agents pursue two simple so-called feasibility goals. The paper uses this framework to shed light on important empirical patterns of asset allocation that are puzzling from the point of view of existing models.Behavioral economics;bounded rationality;equity shares;feasibility goals;life cycle saving;stock market participation

    Public Preferences for Land uses’ changes - valuing urban regeneration projects at the Venice Arsenale

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    This paper discusses the results of a conjoint analysis study developed to assess alternative land uses for an important part of the city of Venice: its Arsenal. Aim of the study is to illustrate the potential of stated preferences techniques for placing a value on redevelopment and reuse alternatives for an underutilized site with high historical, cultural and architectural significance. Very few studies have used conjoint choice to assess public preferences for alternative land uses in an ex-ante framework, i.e. masterplans. For our study, we wanted to concentrate on a “city of art,” where the relationship between cultural heritage resources management and city development is more critical. Venice was an obvious choice for the national and international relevance of its heritage. The Arsenale is one of the few places in Venice that has the potential for a real transformation of its uses, with important impacts on both residents and visitors. Moreover, the Arsenale plays a strong symbolic role: it was the place where the strength and power of the Serenissima was built. The City Council of Venice has recently deliberated that the Arsenale is an inalienable heritage of the city of Venice. In recent years, the importance of the Arsenale has resulted in a heated debate on its possible new uses. Many architectural proposals have been submitted through international competitions. These proposals—whether submitted in the past or currently under consideration—have shown that there may be a conflict between different possible land uses and the transformation allowed by the existing architectural structures. We surveyed individuals in Venice asking respondents to engage in conjoint choice tasks, gathering 168 usable observations. Members of the general public were intercepted at the Multimedia Library at Palazzo Querini Stampalia/FEEM and asked to indicate which choice they preferrd among hypothetical—but realistic—redevelopment projects of the Arsenale historic site. Each project was described by a vector of attributes, such as land use, use of basins and waterways, architectural features, access, employment implied by the reuse, and cost. The responses to these choice tasks was used to infer the rate at which respondents trade off land uses, aesthetic features, and costs, and hence to derive the value of marginal changes in the attributes, and the value of a proposed policy package. The Venice Arsenale is owned by the Italian government and is currently used by the Italian Navy. The Arsenale site accounts for about 15 percent of the area of the city of Venice (about 45 hectares), and is located in the Castello district. Tradition has it that doge Ordefalo Falier founded the Arsenale—a shipbuilding yard—in 1104. In 1340 the “Darsena Nuova” was created, which marked the birth of the Arsenal Nuovo and of the Corderie building. Further expansion started in 1473, covering an area of 26 hectares. This phase lasted more than 100 years, resulting in the construction of the New Corderie building, among others, in 1591. In its heyday, the Arsenale employed roughly 20,000 workers in an assembly-line fashion and produced one ship a day. The Arsenale, after the navy largely withdrew from the complex over 40 years ago, suffered from abandonment and under use. The Arsenale is, therefore, one of the few places in Venice that has the potential for a real transformation of its uses. In this paper we investigate how the development of the Arsenale site, involving alternative land uses, may influence the welfare of the residents of the historical city center of Venice. Starting from the evidence of our survey in Venice, the paper broaden its scope to discuss ways of improving the management of cultural heritage cities, focusing on new forms of involvement and public participation based on public preferences’ elicitation. We debate the issues related to city governance and the need for an appropriate level of democratic participation. An integrated approach, capable of bridging the practice of economic valuation, urban design, conservation of the built environment, and decision-making support systems is here analysed.

    Understanding Household Preferences For Alternative-Fuel Vehicle Technologies

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    This report explores consumer preferences among four different alternative-fuel vehicles (AFVs): hybrid electric vehicles (HEVs), compressed natural gas (CNG) vehicles, hydrogen fuel cell (HFC) vehicles, and electric vehicles (EVs). Although researchers have been interested in understanding consumer preferences for AFVs for more than three decades, it is important to update our estimates of the trade-offs people are willing to make between cost, environmental performance, vehicle range, and refuel¬ing convenience. We conducted a nationwide, Internet-based survey to assess consumer preferences for AFVs. Respondents participated in a stated-preference ranking exercise in which they ranked a series of five vehicles (four AFVs and a traditional gasoline-fueled vehicle) that differ primarily in fuel type, price, environmental performance, vehicle range, and refueling conve¬nience. Our findings indicate that, in general, gasoline-fueled vehicles are still preferred over AFVs, however there is a strong interest in AFVs. No AFV type is overwhelmingly preferred, although HEVs seem to have an edge. Using a panel rank-ordered mixed logit model, we assessed the trade-offs people make between key AFV characteristics. We found that, in order to leave a person’s utility unchanged, a 1,000increaseinAFVcostneedstobecompensatedbyeither:(1)a1,000 increase in AFV cost needs to be compensated by either: (1) a 300 savings in driving cost over 12,000 miles; (2) a 17.5 mile increase in vehicle range; or (3) a 7.8-minute decrease in total refueling time (e.g. finding a gas station and refueling)

    Feeding the cities through urban agriculture the community esteem value

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    The growth of global urban population produces an increase in food demand. With the aim of facing this demand, mainly concentrated in large urban areas, urban agriculture should be fostered to integrate traditional agriculture production, no longer considered sustainable. After suggesting the implementation of integrated systems of urban agriculture, in order to measure their social appreciation expressed by the community, the paper proposes the Community Esteem Value, obtained with a deliberative appraisal procedure

    TOWARD ASSESSING THE NON-MARKET BENEFITS OF EXPERIMENT STATION RESEARCH: A CASE STUDY OF PUBLIC PREFERENCES FOR AES RESEARCH IN RHODE ISLAND

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    This study reports on a survey assessment of the public preferences for the Rhode Island Agricultural Experiment Station's research program. The study summarizes preferences to allocate effort to alternative research projects and estimates the public's willingness to pay to maintain or increase research effort.Teaching/Communication/Extension/Profession,

    Environmental valuation, ecosystem services and aquatic species

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    The thesis consists of an introduction and four articles that can be read independently of each other. The common topic is environmental valuation and cost-benefit analysis. The applications relates to the growing concern of invasive species, and to waterpower externalities. In broad terms, all of the articles relates to water management. Article 1: "A Cost-Benefit analysis of introducing a non-native species: the case of signal crayfish in Sweden", assesses the economic impact of introducing the signal crayfish into a Swedish lake. Two scenarios are set up and compared. The first one assumes that there is no introduction of signal crayfish, so that the noble crayfish is preserved. In the second scenario, the signal crayfish is introduced, which immediately wipes out the entire stock of noble crayfish. The values of noble- and signal crayfish populations are measured as present values of their net future revenues. The values are than compared and net benefit of an introduction is calculated. The result indicate that net benefit of an introduction is positive if the intrinsic growth rate or the carrying capacity of the noble crayfish is below 40 % that of the signal crayfish. Article 2: "Assessing management options for weed control with demanders and non-demanders in a choice experiment", estimates the benefits of having a weed management program for a lake in Sweden, and then compares them with corresponding costs. The policy recommendation from a simple cost-benefit rule is to control the weed at some specific sites of the lake. This paper also suggest how to distinguish those that have a positive WTP for at least one of the attributes (demanders) from those that have zero WTP for all attributes (non-demanders). The advantage of the suggested approach is that it facilitates to more clearly distinguish between conditional and unconditional willingness to pay. The suggested approach could also overcome some of the problems in the literature with negative welfare measures. Article 3: "Assessing transfer errors in the benefit transfer method: An application of invasive weed management using choice experiment", tests the accuracy of transferring benefits of a weed management program from one lake to another using choice experiment. The transfer errors are assessed and the convergent validity hypothesis is tested. Estimating the accuracy of benefit transfer for weed management is policy relevant as there are a number of lakes in Sweden infested with the water weed. The convergent validity was rejected for three out of five welfare estimates with a ten per cent significance level. Article 4: "Willingness to pay for environmental improvements in hydropower regulated rivers", assesses the benefits of environmental improvements along hydropower regulated rivers using choice experiments. Remedial measures that improve the conditions for fish, benthic invertebrates and river-margin vegetation were found to have a significant welfare increasing impact. The results can be of value for the implementation of the Water Framework Directives in Sweden, which aims to reform the use of all surface water and ground water in the member states

    Demonstrating the Value of the Public Library: Economic Valuation and the Advocacy Imperative

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    Promising developments in the field of library valuation over the last fifteen years are providing new options for demonstrating library value. Metrics-gathering has moved away from counting inputs and outputs toward measuring the value of the public library in monetary terms using increasingly sophisticated quantitative methods formerly reserved for business and industry. While it is premature to draw a firm conclusion as to the impact of economic valuation efforts on the success of library advocacy, the adoption of private sector concepts represents a new window of opportunity for library advocates. This critical review synthesizes the library valuation literature, exploring the various frameworks through which library value is being articulated, and finds that econometrics will be most useful to advocates when: 1) library valuation efforts are united with advocacy plans; 2) library services are linked to the achievement of public policy goals; and 3) public libraries are able to connect to a wider funding base
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