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1.
Abstract We show that with symmetric agents, noncooperation is the only stable coalition structure in a fishery with more than two countries. In the case of asymmetric fishing nations, partial or full cooperation may be stable even if the number of countries exceeds two. These are important results for recent fisheries economics papers that have not allowed for coalition formation. As an example how of one can use the model, we study the problem of new entrants into Regional Fisheries Management Organizations (RFMOs). We show that depending on the economic structure of the fishery, new entrants may make cooperation more difficult or easier.  相似文献   

2.
ABSTRACT. In this paper, we examine a game theoretic setting in which four countries have established a regional organization for the conservation and management of straddling and highly migratory fish stocks as recommended by the United Nations Agreement. These countries consist of two coastal states and two distant water fishing nations (DWFNs). A characteristic function game approach is applied to describe the sharing of the surplus benefits from cooperation. We are specifically interested in the effect of possible coalition restrictions on these shares. According to our results the distant water fishing nations, by individually refusing to join with the coastal states, can considerably improve their negotiation position if their harvesting costs are relatively high and similar. The results show that the DWFNs may have economic reasons for negotiating as a group against coastal states. However, if the coastal states are clearly more efficient than the DWFNs then coalition restrictions may be prevented by coastal states.  相似文献   

3.
One of the most ubiquitous of the fishery management problems to have arisen as a result of E.F.J. is that of managing transboundary resources. Economic analysis of this problem rests upon models blending the standard dynamic economic analysis of fisheries with game theory. The analysis reveals that noncooperation is likely to have severe economic consequences and that cooperative arrangements must deal with possible conflicting goals of management, as well as the division of economic returns from the fishery. While the existing economic analysis of transboundary fishery management is far from complete, it can be shown that the analysis is capable of providing important insights into existing real world cases of transboundary resource management.  相似文献   

4.
ABSTRACT. The current paper extends the coalition approach of the management of high seas fisheries to the presence of externalities. The coalition approach is set within the framework of a two‐stage game in which the payoffs depend on the entire coalition structure and are determined through a partition function. The relationship between the presence of externalities and the stability of the coalition structures is explored. The equilibrium coalition structures of the game are also examined. The application of the game to the Northern Atlantic bluefin tuna shows a typical picture of the high seas fisheries: the simultaneous presence of strong externalities in the coalition structures and the absence of stability of the grand coalition. A fundamental conclusion of this paper is that, generally, in order to guarantee the stability of the cooperative agreements it is not sufficient to implement a fair sharing rule for the distribution of the returns from cooperation. Stability requires a legal regime preventing the players that engage in noncooperative behavior from having access to the resource.  相似文献   

5.
本文讨论了满足?A0∈PA(VA0、V(A-A0)∈B→GA0=φ)的可数无穷非原子布尔代数与原子、无原子布尔代数在结构上的关系,给出了任意两个这种类型的布尔代数同构的充要条件,并且对可数无穷非原子布尔代数的结构进行了探讨。  相似文献   

6.
Some features of underdevelopment in Third World countries are reviewed with emphasis on their impact on fisheries and fisheries management. Poverty in rural communities is highlighted as the key issue preventing rational management of tropical inshore fisheries and shown to be - along with (misguided) export-oriented development strategies - the root cause for destructive fishing techniques and environmental degradation. Some implications for modelling are outlined. A reorientation of investments towards job creation in fish-erfolk and other rural communities is advocated as the key aspect of any solution of fisheries problems in Third World countries.  相似文献   

7.
ABSTRACT. In this paper we consider the meaning of sustainable resource management in multi-dimensional resources. Based on the principle of intergenerational fairness, we define fisheries management as sustainable if it does not lead to a decline in the net present value of the fishery. If sustainability, or intergenerational fairness, were held as an obligation by fishery managers, then the traditional present-value maximization objective would be constrained. Using numerical solutions to a simple predator-prey model, we explore how the optimal-sustainable management of this fishery would differ from management that seeks to maximize the present value of the benefits. General lessons regarding the meaning of sustainable fishery management are discussed.  相似文献   

8.
Research and management actions are reviewed with respect to demersal fisheries of the Mediterranean since the Second World War, as reflected in the activities of the General Fisheries Council for the Mediterranean, (GFCM). The scientific background to the priority concern expressed for minimum size limits in the 1960's and 1970's is discussed, and in particular, the mesh selectivity experiments that formed the basis for yield per recruit calculations, with respect to the trawl fishery. More recent considerations, changing our perception of the appropriateness of size at first capture of demersal fish as a management tool in trawl fisheries, are reviewed. It is concluded that for multispecies fisheries where the first priority for fishing effort control is not respected, size limits based on size at maturity, rather than yield per recruit criteria, are more feasible, but that changes in mesh size need to take into account subsequent changes in equity between inshore and offshore fleets, and changes in species composition and areas of distribution during the life history. They also need to consider the high landed value of small fish in many Mediterranean fisheries. Alternative, or supplementary, measures to mesh size regulation that affect capture of small fish are also reviewed, including seasonal closures, closed areas, bans on trawling inshore, and regulations on minimum size at sale. A range of problems to be considered prior to deciding on an increase in mesh size are reviewed, including changes in total effort exerted, changes in increases in fishing power (and especially the impacts on the spawning stock), changes in discard rate, “meshing” of small fish, and indirect mortality during fishing. A strategy for introducing new mesh sizes is suggested, with emphasis, where possible, on the experimental approach, and on supplementary measures to control fishing effort. The paper concludes by considering an alternative paradigm to minimum size regulation for demersal fisheries management; namely, the exploitation of juvenile fish, with provision for escapement of a small proportion of large, mature fish offshore, for which exploitation rate declines and remains low. It is suggested that this strategy may be, de facto, the one prevailing in the small mesh size inshore trawl fishery prior to development of offshore fisheries. The implications of this possibility have to be considered seriously if high effort levels are to be maintained while effective size limits are raised.  相似文献   

9.
Abstract Steady state and dynamic management models are developed for analyzing the Malaysian marine fisheries. These models originate from the theoretical concepts of the natural resource economics namely the open access, limited entry and the intertemporal fishery models. Such management models are deemed necessary because of the need to sustain the depleting resource and degrading environment. Marine fisheries had been managed under open access for a long time before government intervention took effect sometime during the 1960s. Open access and government intervention during the earlier phase of economic development contributed to the immediate pressure on fisheries. Community development programs geared to alleviate poverty among the fishermen apparently contradicted the effort of sustaining fisheries. Even today this fundamental management objective of sustainable development of fishery resource is not fully adhered to. This study suggests that ability to sustain fishery requires government intervention that can direct resource use to steady state or intertemporal optimal levels.  相似文献   

10.
We give a simple game-theoretic proof of Silver's theorem that every analytic set is Ramsey. A set P of subsets of ω is called Ramsey if there exists an infinite set H such that either all infinite subsets of H are in P or all out of P. Our proof clarifies a strong connection between the Ramsey property of partitions and the determinacy of infinite games.  相似文献   

11.
ABSTRACT. . Regional analyses of possible physical and biological effects of global warming in the Barents Sea area have been carried out recently. Based on such studies possible economic impacts of global warming on the Barents Sea fisheries have been quantified, assuming different types of management regimes. The EconSimp2000 model, consisting of the ecosystem model AggMult and the fleet model EconMult have been parameterized based on fleet and catch records from the Norwegian Barents Sea fisheries. The model has been used to study biological and economic impacts of different environmental scenarios representing possible consequences of global warming. The current environmental situation, including normal seasonal and other variations, has been used as a reference scenario. Several biological and economic indicators have been defined in order to evaluate the simulation results of different environmental scenarios and different types of management regimes. The findings support earlier studies where biological and economic impacts of changes in management regime is found to be more pronounced than impacts caused by effects of global warming.  相似文献   

12.
Abstract In this paper, we use stock size, harvest quantity, and fishing effort as strategic variables. We model a two‐agent noncooperative fishery game, where the agents (nations) harvest a common fish stock. The planning horizon is infinite. The model is solved successively using one instrument at a time as the strategic variable in the game. The net present values of fishing and the escapement stock level from the three different models are compared to show how the choice of variables affects the results. The choice of strategic variable is not a trivial one, as the results are shown to be sensitive to the discounting, the stock's rate of growth, and the assumptions about the distribution of the fish in response to harvesting.  相似文献   

13.
Static analysis shows that individual transferable quotas (ITQs) can dramatically increase economic efficiency comparable to a limited entry (LE) management by releasing excess capital. However, the transition from LE to ITQ management presents further efficiency questions. This paper shows that the rate of retirement of excess capital is determined by the opportunity cost of holding ITQ harvest rights on cost inefficient vessels. While restructuring is immediate with perfect foresight, delayed exit occurs with uncertainty and low opportunity costs of holding ITQ. Nearly cost-efficient fishers anticipate increasing their payoff by waiting for higher ITQ prices, e.g., game theoretic principles rather than static Marshallian principles apply. The results raise policy questions about allocating ITQ to incumbent fishers at no charge. The Mid-Atlantic surf clam and ocean quahog fishery which switched from LE to ITQ management in 1990 is analyzed as a case study. Results show that a large surplus was possible but unattained under LE management but also that adjustment has been slow and costly, consistent with the results of this paper.  相似文献   

14.
ABSTRACT. We utilize a spatial bioeconomic model to investigate the impacts of creating reserves on limited‐entry fisheries. We find that reserve creation can produce win‐win situations where aggregate biomass and the common license (lease) price increase. These situations arise in biological systems where dispersal processes are prevalent and the fishery prior to reserve creation is operating at effort levels in a neighborhood of open‐access levels. We also illustrate that using strictly biological criteria for siting reserves (e.g., setting aside the most biological productive areas) will likely induce the most vociferous objections from the fishing industry. In general, we find that the dispersal rate and the degree the patches are connected play a significant role on the net impacts on the fishing sector.  相似文献   

15.
The proliferation of double‐crested cormorants (DCCOs; Phalacrocorax auritus) in North America has raised concerns over their potential negative impacts on game, cultured and forage fishes, island and terrestrial resources, and other colonial water birds, leading to increased public demands to reduce their abundance. By combining fish surplus production and bird functional feeding response models, we developed a deterministic predictive model representing bird–fish interactions to inform an adaptive management process for the control of DCCOs in multiple colonies in Michigan. Comparisons of model predictions with observations of changes in DCCO numbers under management measures implemented from 2004 to 2012 suggested that our relatively simple model was able to accurately reconstruct past DCCO population dynamics. These comparisons helped discriminate among alternative parameterizations of demographic processes that were poorly known, especially site fidelity. Using sensitivity analysis, we also identified remaining critical uncertainties (mainly in the spatial distributions of fish vs. DCCO feeding areas) that can be used to prioritize future research and monitoring needs. Model forecasts suggested that continuation of existing control efforts would be sufficient to achieve long‐term DCCO control targets in Michigan and that DCCO control may be necessary to achieve management goals for some DCCO‐impacted fisheries in the state. Finally, our model can be extended by accounting for parametric or ecological uncertainty and including more complex assumptions on DCCO–fish interactions as part of the adaptive management process.  相似文献   

16.
Fisheries regulation is considered necessary to counteract the effects of competitive forces which can lead to a “tragedy of the commons”. Yet management initiatives have often failed because they did not take into account competitive responses of fishing enterprises. In particular, open access fisheries provide strong incentives for the development of excessive harvesting capacity. This in turn leads to harvesting that is concentrated in space and time, with adverse effects on both the resource and markets. A coalition of fishermen, such as a fishermen's cooperative, has interests similar to those of a sole owner, and thus would be expected to produce more efficient behaviour. In practice, however, fishermen's cooperatives seldom persist. Game theory is used to explore relationships between the coalition structure of the industry, economic variables, and regulation. The models are based loosely on a purse seine fishery for herring. The results suggest that the potential to form stable coalitions is affected by changes in price and harvest. Changes in regulation also affect stability of coalitions. When interpreted in the light of historical changes in the herring fishery, these results suggest that industry may not accept regulations which do not permit formation of stable coalitions.  相似文献   

17.
ABSTRACT. I trace the development of fisheries models (i.e., fish population dynamics models of species subject to fisheries) to the 21st century. The first real efforts occurred in the period 1900 1920 with the work of Baranov (the “Grandfather” of fisheries population dynamics) and the formation of the International Council for the Exploration of the Sea (ICES). The establishment of the science occurred between 1920 1960 with multi‐species modeling, age‐ and size‐structure dynamics, and production models. Fundamental work during this time was done by Ricker (the “Father” of fisheries population dynamics), Beverton and Holt (the “Prophets” of fisheries population dynamics), Chapman, Dickie, DeLury, Graham, Gulland, Leslie, Lotka and Volterra, Russell, Schaefer, and Thompson. During this time, most of the workwas deterministic and mathematical. Between 1960 and 1980, statistical methodology evolved greatly but was separate from mathematical advances for the most part. The development of statistical principles for the estimation of animal abundance was further enhanced by Arnason, Buckland, Burnham and Anderson and White, Cormack, Eberhardt, Jolly, Manly, Pollock, Ricker, Robson, and Seber, among others. Fisheries models evolved in a deterministic setting, with advances in age‐structured models (Gulland, Pope, Doubleday), surplus production models (Pella, Tomlin‐son, Schnute, Fletcher, Hilborn), growth models, bioeconomic models (C. Clark) and management control models (Hilborn, Walters). The period 1980 2000 was the Golden Age. The integration between mathematics and statistics occurred when likelihood and least squares techniques were formally combined with mathematical models of population change. The number of fisheries modelers grew exponentially during this time, resulting in a concomitant increase in publications. A major advance in the 1990s has been the development of Bayesian and time series methods, which have allowed explicit specification of uncertainty. Currently, theory allows realistic modeling of age‐ and size‐structured populations, migratory populations and harvesting strategies. These models routinely incorporate measurement error, process error (stochasticity) and time variation. But data needs often overwhelm the performance of models, and greater demands are being placed on models to answer complex questions. There has been poor communication between fisheries and ecological modelers, between fisheries researchers and statisticians, and among fisheries researchers in different geographic locales. Future models will need to deal better with habitat and spatial concerns, genetics, multispecies interactions, environmental factors, effects of harvesting on the ecosystem, model misspecification and so‐cioeconomic concerns. Meta‐analysis, retrospective analysis and operating models are some modern approaches for dealing with uncertainty and providing for sustainable fisheries. However, I fear that current attacks on single‐species models and management may result in rejection of these advances and an attempt to substitute a less scientific approach.  相似文献   

18.
19.
本文通过构建产权效度的影响效应模型、产权效度的优化模型和最优产权效度的贸易效应模型,分别对产权制度与出口竞争力的关系、最优产权效度的决定机制与影响效应进行了初步分析与论证,并对旨在提高产权效度的制度改革提出了相关建议.  相似文献   

20.
黎杰 《运筹与管理》1997,6(4):83-86
本文以一个利用日元贷款引进的大型水厂自控系统为例,简述了系统实施过程中项目管理的方法,希望对同类引进自控项目有一定的参考价值  相似文献   

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