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1.
Portuguese Economic Journal - Using analytical methods they devised, the authors intend to study economic aspects of the racetrack economy described as a continuous-space version of the new...  相似文献   

2.
This article presents a summary of current information concerning the health and financial costs of workplace smoking, with special emphasis on the costs to union workers and multiemployer health and welfare funds. It describes the potential savings from investing in tobacco cessation for workers and members, provides an overview of scientific evidence concerning the efficacy of different approaches to tobacco cessation, including behavioral services and medications, and discusses some of the benefit design and management issues involved in offering tobacco cessation services to employees and members.  相似文献   

3.
In this paper we discuss the use of optimal control methods for computing non-linear continuous optimal growth models. We have discussed various recently developed algorithms for computing optimal control, involving step-function approximations, Runge–Kutta solutions of differential equations, and we suggest that the discretization approach is preferable to methods which solve first-order optimality conditions. We have surveyed some powerful computer programs by : , and for computing such models numerically. These programs have no substantial optimal growth modelling applications yet, although they have numerous engineering and scientific applications. A computer program named by is developed in this study. Results are reported for computing the Kendrick–Taylor optimal growth model using and programs based on the discretization approach. References are made to the computational experiments with and . The results are used to compare and evaluate mathematical and economic properties, and computing criteria. While several computer packages are available for optimal control problems, they are not always suitable for particular classes of control problems, including some economic growth models. The -based and , however, offer good opportunities for computing continuous optimal growth models. It is argued in this paper, that optimal growth modellers may find that these recently developed algorithms and computer programs are relatively preferable for a large variety of optimal growth modelling studies.  相似文献   

4.
Payments for environmental services (PES) are an innovative approach to conservation that has been applied increasingly often in both developed and developing countries. To date, however, few efforts have been made to systematically compare PES experiences. Drawing on the wealth of case studies in this Special Issue, we synthesize the information presented, according to case characteristics with respect to design, costs, environmental effectiveness, and other outcomes. PES programs often differ substantially one from the other. Some of the differences reflect adaptation of the basic concept to very different ecological, socioeconomic, or institutional conditions; others reflect poor design, due either to mistakes or to the need to accommodate political pressures. We find significant differences between user-financed PES programs, in which funding comes from the users of the ES being provided, and government-financed programs, in which funding comes from a third party. The user-financed programs in our sample were better targeted, more closely tailored to local conditions and needs, had better monitoring and a greater willingness to enforce conditionality, and had far fewer confounding side objectives than government-financed programs. We finish by outlining some perspectives on how both user- and government-financed PES programs could be made more effective and cost-efficient.  相似文献   

5.
The Value of the World's Ecosystem Services and Natural Capital by Costanza in 1997 is generally regarded as a monumem for the research of valuing ecosystem services. However, the classification of ecosystem services, the method of various services summation and the purpose for static global value had be confronted by many criticisms. Based on the summary of these criticisms, suggestions, related function assessment and further study direction, the sustainability of ecosystem Services is presented. The two basic indicators in ecology, productivity and biodiversity, respectively charactering the ability of producing and self-organizing, not only represent the internal function of ecosystem, but also are proportioned to its external function of supporting and providing for human life. On presenting the general.form of ecosystem services assessment, this paper improves the mathematical formula by giving a function adjusting coefficient composea of productivity and biodiversity. Theoretically, the integration of the two indicators reflects the changes of ecosystem services at spatial and temporal scales, can physically assess the sustainability of ecosystem services, and build a firm scientific fundament of value assessment for ecosystem services. Objectively, its application should be strictly tested in next step.  相似文献   

6.
In this paper we estimate a continuous time macro-econometric model of the Czech economy. The model is built as a system of twelve non-linear differential equations. We illustrate how the model can be used to determine the nominal equilibrium exchange rate of the Czech koruna in a macro-economic framework. The paper also investigates the effectiveness of monetary and fiscal policies in the presence of a fixed exchange rate regime and massive capital inflows. The search for an equilibrium path is outlined and stability and sensitivity analyses are provided, along with in-sample static and dynamic predictions with the approximate discrete analogue.  相似文献   

7.
We construct a model of multi-unit auctions in which I bidders bid for two indivisible units of a common value good. Using a first-order approach, we find that there are equilibria in which bidders bid the same price for both units in the discriminatory auction, but not in the uniform auction. When there are only two bidders, under certain conditions, there are linear equilibria for both the discriminatory and the uniform auction formats. In all equilibria, bidders equalize the expected marginal benefit of bidding to the marginal costs of bidding. We show that comparison of the seller??s expected revenue across auction formats depends only on the ratio of the precision of private information to the precision of public information.  相似文献   

8.
政府购买公共服务是政府履行公共服务职能的一种创新。长沙市政府在购买公共服务实践中形成了自己的特点,本文在分析其不足的基础上提出了可供借鉴的改进意见。  相似文献   

9.
This paper introduces a new, more realistic characterization of local public services. This characterization fits education, parks, and streets, none of which are a pure Samuelsonian good. It is shown that Tiebout's hypothesis holds for this new type of services, provided correct user charges are adopted. Introducing several local services considerably affects the results. The paper emphasizes the difference in tastes with regard to quality as opposed to quantity. Earlier literature is shown to apply to the role of quality and ignores the role of quantity. The effect of the latter makes mixed communities more efficient than segregated ones. It is shown that efficient allocation with mixed communities is an equilibrium in a costless mobility, Tiebout-type setting.  相似文献   

10.
An empirical assessment of a continuous time portfolio selection model is studied for the UK economy between 1970 and 1996. The estimates obtained from this study are both statistically significant and consistent with the model's predictions. The estimate of risk aversion parameter refers to low risk aversion which is consistent with the optimal risky asset holding parameter. Furthermore, the estimated parameters of the asset pricing relationship are also found to be consistent with the historical values of the stock prices. First version received: February 1998/final version received: March 1999  相似文献   

11.
The purpose of this article is to examine a continuous model of job search. Job offers are received randomly over time according to a renewal process. The wage offers are assumed to be positive, independent, and identically distributed random variables. There is a search cost of c monetary units per unit time. The only decision the searcher must make is when to stop searching and accept an offer. It is shown that the optimal stopping strategy which maximizes the searcher's expected net return over the class of all stopping times possesses the reservation wage property, provided that the interarrival time between two successive job offers in NBUE (new better than used in expectation).  相似文献   

12.
The aim of this paper is to assess the possible contribution of an input-output model towards two of the basic principles of the sustainability strategy of integrated coastal zone management (ICZM) and Post-Normal Science. According to these principles, decision-support tools should offer a holistic perspective and handle high uncertainty. The difficulties in reaching sustainability are due partly to the prevailing use of “narrow-system-boundary” tools that are non-holistic. Consequently, they fail to capture important ecosystem services and ignore interdependencies between them. To comply with the basic principles, our method allows environmental assets to be evaluated in multiple units and integrates results from recent researches in natural sciences. Both enable coverage of interdependencies between ecosystem services. Thereby, we enlarge input-output modelling from the two conventional ecosystem services of sink and provisioning to the most vital ones: the supporting services. An application to the Seine estuary addresses the impacts of maritime transportation infrastructures on nursery habitats for commercial fish. The ecosystem services covered are life support and resource provisioning. Our results show that the restoration of a total of 73.7 km2 of nursery areas over the period 2004-2015 would result in a stock of sole in 2015 that exceeds the “business as usual” scenario by 44.2% (uncertainty range: 35.9%-69.9%). In spite of high restoration costs, the negative macro-economic impact is very low. However, on the sector level, a trade-off results between nurseries and three economic sectors. The quantification of such trade-offs in our model is particularly useful to public participation in decision-making.  相似文献   

13.
The emergence of profit-based online platforms related to the Sharing Economy, such as BlaBlaCar and Airbnb, provides new means for end users to create an income from their possessions. With this opportunity, participants have to make strategic economic decisions despite limited formal expertise and information. Decentralization (using digital technologies) and reputation (using user reviews) are the core mechanisms chosen by these platforms to mitigate these limitations and to work efficiently as online matchmakers. We test the performance of these two mechanisms by studying the allocative efficiency (in terms of value and volume of transactions) of simulated marketplaces under different types of motivation from the participants and control from the platforms. As a result, we find an inverted-U relationship between the decision-making leeway available to the participants and the platform’s allocative efficiency. From the participants’ perspectives, too much freedom or too many barriers lead to market failures affecting specific participants: low-end consumers are banned from the marketplace while high-end providers experience lower levels of activity. As governance advice for these platforms, we show the limitations of promoting these platforms on the sole motive of monetary rewards.  相似文献   

14.
As telecommunication market becomes more competitive and the customers' expectations regarding services or products increases, understanding customer or market needs is at the center of successful telecommunication business.In this study, we attempt to explore the intention of using mobile services based on the Warshaw's purchase intention model. We also focus on a personal innovativeness in the domain of IT (PIIT) because we assumed that as characteristics of telecommunication services become increasingly sophisticated, personal innovativeness could be a key factor of telecommunication services usage. In this study, we examine whether PIIT has the moderating effect on purchasing mobile-RFID services.The result shows that both purchasability and perceived need collectively explain purchase intention of mobile-RFID services, as well as PIIT serves to moderate the relationship between perceived need and purchase intention of mobile-RFID services. The study findings also indicate that IT knowledge, responsiveness to IT news and ability to use mobile phone of customers are positively related with PIIT.  相似文献   

15.
This paper describes the first application to an economy-wide macroeconometric model of recently developed methods for the exact Gaussian estimation of higher order continuous time dynamic models. The new model is formulated as a system of second order differential equations, thus providing a much richer dynamic specification than the predominantly first order continuous time macroeconometric models developed during the last 15 years. It also makes intensive use of economic theory to obtain a parsimonious parametrization, is designed in such a way as to permit a rigorous mathematical investigation of its steady state and asymptotic stability properties, and makes systematic use of the assumption of long-run rational expectations. In addition to the exact Gaussian estimates of the structural parameters, the paper includes the first set of continuous lag distributions derived from estimates that take account of the exact restrictions on the distribution of the discrete data implied by a continuous time model. It also includes the first estimates of the coefficient matrices of the exact discrete model, in its VARMAX form, satisfied by the discrete stock and flow data generated by a higher order continuous time dynamic model.  相似文献   

16.
A method of constructing a deficit-having model of exchange based on the Markov chain theory for continuous processes with external control is developed, for which the results of the continuous and discrete models are identical. Continuous models allow us to study and predict exchange processes at any moment in time. The deficit model assumes that in the exchange process, when a stationary regime is achieved, those involved have a nonzero balance. The model allows us to determine the external force (control – the actions of the administration) for the realization processes of a specific exchange programme.  相似文献   

17.
The traditional income–leisure model treats income as a composite commodity; it is not appropriate for studying commodity subsidies which alter relative prices within the composite. I suggest reinterpreting the traditional model as a special case of a utility function weakly separable with respect to leisure and all other commodities. This interpretation allows the work incentive effects of any subsidy program to be inferred from the terms of the program and data on the work effort effects of any other subsidy program, most notably income maintenance experiments. I illustrate the approach by estimating the work incentive effects of public housing. The model implies that even if special complementaries between leisure or work and the subsidized good are neglected, in-kind transfers will have different work incentive effects than equivalent cash transfers. In practice, in-kind transfers will generally stimulate work effort vis-à-vis equivalent cash grants.  相似文献   

18.
In an integrated economic/ecological model, the economy benefits from ecosystem services that include: (1) the consumptive use of a harvested species, (2) the non-consumptive use of popular species, and (3) naturalness, i.e., the divergence of the ecosystem’s biodiversity from its natural steady state. The biological component of the model, which is applied to a nine-species Alaskan marine ecosystem, relies on individual optimizing behaviour by plants and animals to establish population dynamics. The biological component is used to define naturalness. By varying harvesting we arrive at different steady-state populations and humans choose from among these steady states. Welfare maximizing levels of the ecosystem services are derived, then it is shown that in the laissez-faire economy overharvesting occurs when the harvesting industry ignores ecosystem services (2) and (3). Lastly, we introduce efficiency restoring taxes and standards that internalize the ecosystem externalities.
John TschirhartEmail:
  相似文献   

19.
Estimation, inference and interpretation of the causal effects of programs and policies have all advanced dramatically over the past 25 years. We highlight three particularly important intellectual trends: an improved appreciation of the substantive importance of heterogeneous responses and of their methodological implications, a stronger focus on internal validity brought about by the “credibility revolution,” and the scientific value that follows from grounding estimation and interpretation in economic theory. We discuss a menu of commonly employed partial equilibrium approaches to the identification of causal effects, emphasizing that the researcher's central intellectual contribution always consists of making an explicit case for a specific causal interpretation given the relevant economic theory, the data, the institutional context and the economic question of interest. We also touch on the importance of general equilibrium effects and full cost–benefit analyses.  相似文献   

20.
Despite billions of dollars of public appropriations to state purchase of development rights (PDR) programmes, there has been limited evaluation of the effects of these investments on the economic performance of preserved farms. This article estimates dose-response functions to evaluate the effects of enrolment in New Jersey’s PDR programme on farm profitability. The generalized propensity score method in a continuous treatment setting is used to address selection bias arising from voluntary programme participation. Treatment effects are measured across treatment levels to determine whether farm profitability is affected differently across levels of programme participation. Our findings reveal that, relative to unpreserved farms, profit per acre tends to increase along lower treatment levels. The profit per acre of preserved farms in the 1–40% treatment range is, on average, $407 higher than that of unpreserved farms in the full sample. Positive profit differentials averaging between $317 and $472 per acre are also observed in the 1–20%, 1–40% and 1–60% treatment quintiles in the farming occupation sample. We do not observe statistically significant profitability differentials when treatment effects are averaged across all positive treatment values.  相似文献   

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