ecological economic viability as a criterion of strong sustainability under uncertainty strong sustainability according to the common definition requires that different natural and economic capital stocks be maintained as physical quantities separately yet in a world of uncertainty this cannot be guaranteed to therefore define strong sustainability under uncertainty in an operational manner we propose to use the concept of viability viability means that the different components and functions of a dynamic stochastic system at any time remain in a domain where the future existence of these components and functions is guaranteed with sufficiently high probability we develop a unifying and general ecological economic concept of viability that encompasses the traditional ecological and economic notions of viability as special cases it provides an operational criterion of strong sustainability under a mild form of uncertainty and for medium spatial and temporal scales we illustrate this concept and demonstrate its usefulness by applying it to livestock grazing management in semi arid rangelands publication ecological economic viability as a criterion of strong sustainability under uncertainty available from https www researchgate net publication 46490456 ecological economic viability as a criterion of strong sustainability under uncertainty accessed apr 3 2017

economic viability and small scale fisheries a review abstract globally over 90 of all fishing vessels and about 22 million fishers are considered small scale despite their high numbers small scale fisheries are often understudied they are usually economically and politically marginalized and therefore vulnerable to large scale threats e g globalized markets to support this sector and contribute to its sustainability we argue that it is fundamental to understand how economically viable small scale fisheries are hence the main objective of this article is to critically review and describe the current discourse on the economic viability of small scale fisheries we find that currently economic viability is mainly equated with financial viability where profitability is the goal in consideration of socio economic aspects the maintenance of nonnegative net benefits to society is often not considered in current notions of economic viability while these shortcomings have been acknowledged in some of the existing literature our review shows that they have not yet been addressed comprehensively we therefore conclude that it is necessary to develop or expand current methods to better take into account social aspects when assessing the economic viability of small scale fisheries this would help find solutions to make these fisheries less vulnerable and better equipped to face large scale processes of change

developing effective policies for the sustainable development of ecological agriculture in china the case study of jinshan county with a systems dynamics model abstract this paper focuses on a search for concrete policy measures to facilitate the overall sustainability of ecological agricultural development at a county level for this purpose a system dynamics model aiseem has been developed to explore the potential long term ecological economic institutional and social interactions of ecological agricultural development through a case study of jinshan county in china the model provides an experimental platform for the simulation and analysis of alternative policy scenarios the results indicate that the diversification of land use patterns government low interest loans and government support for training are important policy measures for promoting the sustainable development of ecological agriculture at least in the case study context in addition the study reveals that environmentally sound technology e g biogas project alone cannot sufficiently induce farmers to adopt ecological agricultural practices limited availability of information risk aversion and high transaction costs are major barriers to the adoption of alternative agricultural practices in this regard the importance of capacity building and institutional arrangements are emphasised through the development of an improved policy making process on agricultural sustainability this case study highlights the importance of combining the ecological economics analytical framework with the system dynamics modelling approach as a feasible integrated tool to provide insight into the policy analysis of ecological agriculture and thus set a solid basis for effective policy making to facilitate its sustainable development on a regional scale

simulating the effects of environmental and market variability on fishing industry structure abstract an agent based model comprising a fish stock a fishing fleet and a fish market is used to investigate the combined effects of environmental and market variability on the structure of a fishery over 15 year simulations agents make daily fishing decisions and annual entry exit and investment decisions based on the fishery s past economic outcomes and their individual risk preferences and opportunity costs e g an alternative source of income environmental variability is simulated through fishing success variability while market variability is simulated through changes in the elasticity of the demand curve i e the responsiveness of market prices to changes in daily landings our findings indicate that changes in variability lead to changes in economic and biological conditions of the fishery by influencing the composition of risk preferences within the fleet counter to expectations market stability did not dampen the negative impacts of environmental variability but rather stimulated over investment and increased harvesting by a small number of risk seeking fishers results from this research suggest that climate driven increases in fisheries variability coupled with increases in market integration that act to reduce local price signals may lead to inefficient investments and reduced fishery resources

the triple bottom line meeting ecological economic and social goals with individual transferable quotas this paper deals with the sustainable management of a renewable resource based on individual and transferable quotas itqs when agents differ in terms of harvesting costs or catch capability in a dynamic bio economic model we determine the feasibility conditions under which a fishery manager can achieve sustainability objectives which simultaneously account for stock conservation economic efficiency and maintenance of fishing activity for the agents along time we show how the viability of quota management strategies based on itq depends on the degree of heterogeneity of users in the fishery the current status and the dynamics of the stock together with the selection of tac schedules in particular for a given stock we compute the maximin effort for a given set of agents and we derive the maximal number of active agents for a given guaranteed effort an application to the nephrops fishery in the bay of biscay illustrates the results

storage and viability of a fishery with resource and market dephased seasonalities in this study we analyse the role of the storageregulation in a fishery s production process when theresource exploited and the market to which theproduction is exported are characterized by seasonaldephased oscillations for this purpose we built up adynamic model drawn from the french guyana shrimpfishery example the underlying objective of the modelis not the maximisation of a given criterion as wouldbe in the optimal control approach but merely themaintenance of the fishery s economical viability thefundamental principle is here to try to preserve asmany as possible viable control options theconditions to achieve and maintain this viability arecaptured in a certain number of constraints theanalysis points out periods and situations within theseason where the fishermen must anticipate theevolution of their storage to avoid violating thoseviability constraints the study also indicates howthe fishery s viability can be ensured even if theexploitation costs exceed the commercial value of thelandings for a finite part of the year however whenthe resource s and or market s oscillations are toolarge the fishery may be not viable any longer and itappears that the crisis can not be removed byinvesting in larger storage capacities

a qualitative dynamical modelling approach to capital accumulation in unregulated fisheries capital accumulation has been a major issue in fisheries economics over the last two decades whereby the interaction of the fish and capital stocks were of particular interest because bio economic systems are intrinsically complex previous efforts in this field have relied on a variety of simplifying assumptions the model presented here relaxes some of these simplifications problems of tractability are surmounted by using the methodology of qualitative differential equations qde the theory of qdes takes into account that scientific knowledge about particular fisheries is usually limited and facilitates an analysis of the global dynamics of systems with more than two ordinary differential equations the model is able to trace the evolution of capital and fish stock in good agreement with observed patterns and shows that over capitalization is unavoidable in unregulated fisheries r 2005 elsevier b v all rights reserved

ecological and economic sustainability in fishery management a multi agent model for understanding competition and cooperation recent studies have shown that many marine ecosystems are experiencing an accelerating loss of population and biodiversity it is apparent that there is a growing disparity between the available supply of fish and the desire of the growing world population to catch them although studies have begun to question the ecological sustainability of managed fishery systems they often omit the corresponding effects on the economic sustainability of fishery industries this is particularly important in rural coastal areas where the fishing industry is often a dominant employer in this article we analyze the interactions between economic and ecological dynamic systems using a multi agent dynamic model of fishery management multiple agents fishers harvest multiple fish species and adapt the amount and allocation of their effort to their value functions which are given as net profits of the fish harvest sold for a market price this is largely unique in fishery models since many econometric studies view fishers as represented by homogenous average agents we introduce and compare two different decision rules governing the behavior of fishers engaged in a competitive market we demonstrate a situation where both behaviors lead to a decline of all fish stocks as well as profits for most fishers as an alternative we introduce a cooperative approach in which fisheries jointly set sustainable limits for total harvest and effort that are then distributed to the fishers according to distribution rules the simulation reveals that fish stocks and profits can stabilize at significantly higher levels in the cooperative case leading to a continuous accumulation of capital for all fishers this model demonstrates key aspects of overfishing conflicts that can be overcome through planned fishing quotas and cooperative market mechanisms it also demonstrates a novel approach for simulating the dynamic behavior of heterogeneous fishers

a viability analysis for a bio economic model abstract this paper presents a simple dynamic model dealing with the management of a marine renewable resource but instead of studying the ecological and economic interactions in terms of equilibrium or optimal control we pay much attention to the viability of the system or in a symmetric way to crisis situations these viability crisis situations are defined by a set of economic and biological state constraints the analytical study focuses on the compatibility between the state constraints and the controlled dynamics using the mathematical concept of viability kernel we reveal the situations and if possible management options to guarantee a perennial system going further we define overexploitation indicators by the time of crisis function in particular we point out irreversible overexploitation configurations related to the resource extinction

system behaviour modelling for demand response provision in a smart grid while pilot projects in the smart grid domain have abounded through public and private efforts there is still uncertainty in identifying effective business models for the smart grid in this paper we take the view of a new entrant in this market acting as a third party provider of demand response new entrants are a key player in emerging technological domains but simulation and policy analysis from this perspective have not been forthcoming we present a novel approach for evaluating business models within a regulatory context and avoid committing to specific technical solutions but instead embark on a parameter exploration through simple yet insightful agent based models our simulations analyse the impact of system performance by three key variables participant population size household flexibility in terms of the maximum number of dr events allowed and size of load shifting shedding available the simulations indicate that benefits of avoided capital investment leads to valuing a participating household at approximately 1800 over a 20 year period these results show how mandated infrastructure influenced by policy can affect the value proposition of a demand response service and provide a useful reference for system level parameter requirements with weak business models policy decisions can be crucial in providing the impetus needed to spur growth in this market

strategic policy for product r d with symmetric costs in this paper i examine strategic policy for product r d in an international duopoly where domestic and foreign firms are identical it is shown that strategic r d policy is described by a subsidy schedule contingent on firms quality choices unilateral policy enables its domestic firm to produce a high quality product making equilibrium outcome unique with two active governments in equilibrium they implement different subsidy schedules two equilibrium outcomes exist which are identical except for the identity of the countries thus both countries have an equal chance to become the high

do women shy away from competition do men compete too much we examine whether men and women of the same ability differ in their selection into a competitive environment participants in a laboratory experiment solve a real task first under a noncompetitive piece rate and then a competitive tournament incentive scheme although there are no gender differences in performance men select the tournament twice as much as women when choosing their compensation scheme for the next performance while 73 percent of the men select the tournament only 35 percent of the women make this choice this gender gap in tournament entry is not explained by performance and factors such as risk and feedback aversion only playa negligible role instead the tournament entry gap is driven by men being more overconfident and by gender differences in preferences for performing in a competition the result is that women shy away from competition and men embrace it

collaboration incentives endogenous selection into single and coauthorships by surname initial in economics and management many prior studies suggest that default alphabetical ordering of coauthors in economicsconfers disproportionate professional advantages on those with an early surname initialbecause of the greater prominence it gives to the first author however these studies do notconsider that authors select into coauthorships according to the incentives identified wedevelop a model of endogenous selection into single and coauthorships around the principlethat no one wants to be second author when they expect to provide the larger contribution i e are of higher quality we test it with authorship data from economics with man agement which does not use default alphabetical ordering as a benchmark we predict foreconomics that lower quality authors with an early surname initial would be less desirablecoauthors whereas higher quality authors with a late initial would have a lower desire tocoauthor most desired are early initial authors of high quality who are therefore advan taged in forming high quality collaborations the combined effect predicts citation rankincreases with surname initial for single authored papers and decreases for coauthored we find both effects for economics when compared to management and absolutely ourfindings indicate that part of the advantage enjoyed by early surname initial authors in eco nomics could be due to the higher ability among them having more incentive compatiblecollaborators rather than merely to greater prominence

women in economics moving up or falling off the academic career ladder copyright 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 by the american economic association

recognition for group work gender differences in academia abstract how is credit for group work allocated when individual contributions are not observed i use data on academics publication records to test whether demographic traits like gender influence how credit is allocated under such uncertainty while solo authored papers send a clear signal about ability coauthored papers are noisy providing no specific information about each contributor s skills i find that men are tenured at roughly the same rate regardless of coauthoring choices women however are less likely to receive tenure the more they coauthor the result is much less pronounced among women who coauthor with other women

international fisheries agreements a game theoretical approach this paper surveys the application of game theory to the economic analysis of international fisheries agreements the relevance of this study comes not only from the existence of a vast literature on the topic but especially from the specific features of these agreements the emphasis of the survey is on coalition games an approach that has become prominent in the fisheries economics literature over the last decade it is shown that coalition games were first applied to international fisheries agreements in the late 1990s addressing cooperative issues under the framework of characteristic function games then progressively this cooperative approach was combined with non cooperative elements such as the stability analysis of the agreements finally partition function games which model coalition formation endogenously were introduced and became the standard approach to study the formation and stability of international fisheries agreements a key message that emerges from this literature strand is that self enforcing cooperative management of internationally shared fish stocks is generally difficult to achieve hence the international legal framework and regulations play a decisive role on ensuring cooperation over the use of these resources

managing interacting species in unassessed fisheries abstract this paper addresses the management of multispecies fisheries and suggests the use of restricted fishing policies as an interesting option for unassessed fisheries as is the case within developing countries specifically we consider a predator prey system under two potential management policies an unrestricted regime where agents can compete to harvest from both species and a second one where they are allowed to harvest only predators the performance of both policies is compared from an ecological and an economic point of view for a sufficiently large number of agents or for strong biological interaction parameters the assumed restricted fishing policy yields both higher long run stock levels and profits thus this contribution suggests that such a policy while requiring weaker monitoring governance than instruments based on outputs such as quotas or taxes would meet environmental and economic objectives finally several features of the analysis are discussed including targeting prey instead of predator and the issue of compliance

on uncertain renewable resource stocks optimal harvest policies and the value of stock surveys abstract annual harvest quotas are commonly employed in the management of renewable resource stocks commercial fisheries being a prime example such resource stocks often undergo quite significant natural fluctuations to which quotas must be adapted a further complication arises from the fact that estimates of stock abundance are often highly uncertain in this paper a bayesian approach is used to model optimal quota decisions for an uncertain fluctuating renewable resource stock

divide and conquer multiple leasing in common pool oil fields a theoretic model is developed to analyse strategic leasing behaviours of u s landowners in a non exclusively owned common oil pool oil field development is modelled as a simultaneous move two stage non cooperative game the landowners choose leasing strategies in the first stage independent lease operators choose extraction strategies in the second ownership structure is distinguished from operation structure and their relationship analyzed it is shown that in a non exclusively owned oil field it is individually rational for a landowner to subdivide his landholding and delegate production rights to multiple inde pendent firms although more dispersed production control leads to heavier common pool

up the average cost curve inefficient entry and the new protectionism abstract a two country model is developed in which each country produces one good with increasing returns the goods being perfect or imperfect substitutes with cournot nash behavior and free entry certain restrictive trade policies have effects opposite to their favorable effect under noentry assumptions import tariffs and export subsidies lead to inefficient entry that raises rather than decreases the average production cost of and price charge by the domestic industry with negative welfare consequences we argue that these predictions of our model are closely consistent with extensive canadian data on entry exit and firms responses to trade liberalization

an open access fishery with rational expectations explain the evolution of the fish stock and the boat fleet as well as determine their equilibrium levels 2 while the changes in the fish stock are described by a biological rule entry and exit from the fishing industry are determined by how expectations are formed we examine a general model in which entry and exit are proportional to the present value of expected profits and compare two special cases of adaptive myopic expectations and rational expectations although both expectations mechanisms lead to the same equilibrium values they lead to different adjustment paths where expectations solely depend on current values myopic expectations it is well known that boats enter the fishery only when the fish stock is greater than its steady state stock 3 with rational expectations however boats may enter when the fish stock is much lower than its steady state value provided the boat fleet is sufficiently small this difference in adjustment is observable and in principle leads to an obvious test on how agents form expectations section 2 develops a general dynamic model for studying fisheries in section 3 we show that the model standardly used in the literature is equivalent to a myopic adaptive expectations model a rational expectations model is analyzed in section 4 the standard and rational expectations models are compared in section 5 section 6 illustrates this comparison using a simulation based on a schaefer model of the pacific halibut fishery section 7 presents the conclusions

divisionalization franchising and divestiture incentives in oligopoly a two stage game is used to model firms strategic incentives to divide production among autonomous competing units through divisionalization franchising or divestiture firms simultaneously choose their number of competing units which then engage in cournot competition while it is costly to form autonomous units each firm does so in equilibrium thus reducing firm profits and increasing social welfare relative to the case where firms cannot form competing units with linear demand and costs duopolists choose the socially optimal number of competing units oligopolies with larger numbers of firms choose too many the case of nonlinear demand is also examined copyright 1996 by american economic association

strategic r d policy under vertically differentiated oligopoly in this paper strategic rd and the high tech firm s government always gains in the r d policy game in contrast to the standard prison

on conflict over natural resources abstract this paper considers a game theoretic framework of repeated conflict over natural resource extraction in which the victory in each engagement is probabilistic and the winner takes all the extracted resource every period each contesting group allocates its capabilities or power between resource extraction and fighting over the extracted amount the probability of victory rises with fighting effort but a weaker group can still win an encounter the victorious group wins all of the extracted resources and converts them to power and the game repeats in one model groups openly access the resource in a variant of the model the stronger group can access a larger part of the resource than its rival while in a second variant of the model the advantage of the dominant group is made more decisive than in the first two models our models generate outcomes that mimic several aspects of real world conflict including full military mobilization defeats in one or repeated battles victories following defeats changes in relative dominance and surrender we examine comparative dynamics with respect to changes in the resource attributes resource extraction initial power allocation fighting capabilities and power accumulation the policy implications are evaluated and future research avenues are discussed

a model of regulated open access resource use abstract this paper develops a model of regulated open access resource exploitation the regulatory model assumes that regulators are goal oriented choosing target harvest levels according to a safe stock concept these harvest quotas are implemented by setting season lengths conditioned on the industry fishing capacity the industry enters until rents are dissipated conditioned on season length regulations harvest levels fishing capacity season length and biomass are determined jointly using parameter estimates from the long regulated north pacific halibut fishery predictions of these variables from the regulated open access model are compared to predictions that arise from the gordon model

international fish wars the strategic roles for fleet licensing and effort subsidies abstract this article examines the problem of noncooperative international fishing by analyzing the strategic rent shifting roles for such well known national management policies as fleet licensing and effort subsidies it is shown that the noncooperative equilibrium in each policy takes the form of a prisoner s dilemma with dissipated rents in the fishery it is also shown that strategic effort subsidies can only lead to incomplete rent dissipation but strategic fleet licensing can lead to complete rent dissipation the models developed in this article may help to provide an explanation for the persistence of large and excessively subsidized national fleets that exploit depleted international fish stocks

challenges for economic policy in sustainable management of marine natural resources the sustainable management of marine natural resources presents particular challenges to the managers of those resources while such management has typically been based on biological considerations it is argued that this has resulted in overexploitation and destruction of important marine assets in industries such as fishing and tourism consequently it is concluded that other approaches are needed with the use of economic concepts and management tools particularly relevant at the same time the human welfare outcomes of the application of various policy instruments must be carefully considered while biological information is critical to the formulation and implementation of successful management regimes it is concluded that the application of economic instruments will become more attractive to resource managers with these instruments underpinned by consideration of property rights and an appropriate allocation of economic rents a greater focus on these economic matters will take resource managers further in the direction of sustainable management of increasingly scarce marine resources the conclusions in the paper are supported by various case studies from fisheries and tourism 2001 elsevier science b v all rights reserved

assessing efficiency gains from individual transferable quotas an application to the mid atlantic surf clam and ocean quahog fishery delayed fishing fleet restructuring complicates the assessment of efficiency gains from individual transferable quota itq fisheries management programs this article presents a methodology to estimate harvest sector efficiency gains in lieu of incomplete fleet restructuring the methodology is applied to assess the efficiency gains in the mid atlantic surf clam and ocean quahog fishery itq program while roughly 128 vessels harvested clams under the previous management regime the analysis suggests that 21 25 vessels will remain under ltqs the efficiency gains are estimated to be between 11 1 million and 12 8 million annually 1990 dollars

an adjustment restriction on fish quota resource rents overcapacity and recovery of fish stock management objectives of the european union for north sea fish stocks are shifting towards considering both biological sustainability and economic benefits as part of multiannual management plans an adjustment restriction on fish quota has been introduced its objective is to obtain an efficient fish stock and to reduce overcapacity for the fishing industry we develop and apply a bi level stochastic dynamic programming model to study the effect of a quota adjustment restriction on the net present value of resource rents overcapacity and fish stock when the system is recovering from a downward environmental shock at level one a policy maker sets the quota considering fishermen behavior stochastic fish stock dynamics capital stock dynamics and a quota adjustment restriction at level two fishermen harvest myopically and make long term investment decisions assuming that fish stock and quota do not change over time the two levels are linked by the quota which is optimized by the policy maker at level one and becomes a restriction for myopic harvest and long term investment decisions of fishermen at level two our analysis suggests that in the long run overcapacity can be reduced by 54 at modest costs namely at a 1 reduction in the net present value of resource rents long and short run sustainability of the fish stock is not affected

between group competition enhances cooperation in resource appropriation games abstract cooperation in public goods games increases in the presence of between group competition in this study we validate the effect of between group competition in a different social dilemma a resource appropriation game unlike the voluntary contributions setting group performance in this game increases with the exercise of a passive choice not appropriating units in an open access resource we conducted an incentivized experiment using 276 undergraduate students in which groups of four subjects played a resource appropriation game different groups within a session were ranked in each round according to the group s aggregate payoff this ranking determined a group performance multiplier which increased the payoffs in groups ranked above the median and decreased the payoffs in groups below the median the multipliers were small enough to keep the individual benefits from appropriation larger than the individual benefits from a higher payoff multiplier derived from an improvement in group ranking by not appropriating the resource unit we found that implementing this small group performance multiplier decreased the average appropriation by 31 this efficiency enhancing device generated a 19 percentage point increase in overall earnings in a given session

the sensitivity of strategic and corrective r d policy in battles for monopoly the authors characterize the role for r d subsidies in export markets where r d is an uncertain process and the winner of the r d competition monopolizes the market investments are assumed to induce either first order or mean preserving second order shifts in the distribution of a firm s costs or reinterpreting the model as a patent race a firm s discovery dates the authors show that regardless of which form the uncertainty takes a national strategic incentive to subsidize r d exists but must be balanced against a national corrective incentive to tax r d whenever a country has multiple firms involved in the r d competition copyright 1992 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

the diffusion of consumer durables in a vertically differentiated oligopoly in a vertically differentiated durable goods duopoly prices tend to decline over time because the high quality manufacturer s future product may compete more directly with the other firm s present product than with its own this removes the standard reason not to cut prices stokey 1979 price levels depend not only on the similarity of the two products but also on how readily the low quality manufacturer s customers abstain from purchasing in order to obtain the high quality good at a reduced price in the future when quality choice is endogenized substantially less vertical differentiation arises than would occur for nondurables

ecoviability for small scale fisheries in the context of food security constraints this paper applies a stochastic viability approach to a tropical small scale fishery offering a theoretical and empirical example of ecosystem based fishery management approach that accounts for food security the model integrates multi species multi fleet and uncertainty as well as profitability food production and demographic growth it is calibrated over the period 2006 2010 using monthly catch and effort data from the french guiana s coastal fishery involving thirteen species and four fleets using projections at the horizon 2040 different management strategies and scenarios are compared from a viability viewpoint thus accounting for biodiversity preservation fleet profitability and food security the analysis shows that under certain conditions viable options can be identified which allow fishing intensity and production to be increased to respond to food security requirements but with minimum impacts on the marine resources

decentralized regulation of a common property renewable resource industry with irreversible investment abstract the effectiveness of output controls for rationalizing a common property renewable resource has been called into question by the theoretical work of j r gould economica nov 383 402 1972 a proper examination of this question requires an intertemporal analysis one that takes into account that asymmetries between persistent factors of production immaleable capital and factors that are instantaneously consumed labor or ldharvest effort we present here a nonlinear intertemporal model of a renewable resource industry under conditions of irreversible capital investment and undertake to analyze its dynamics both at open access and under centralized optimal management we then examine the theoretical possibility of decentralized regulation by pigouvian taxes and reconsider the proposition of gould

international r d rivalry and industrial strategy this paper presents a theory of government intervention which provides an explanation for industrial strategy policies such as r d or export subsidies in imperfectly competitive international markets domestic net welfare is improved by the capture of a greater share of the output of rent earning industries although the subsidy ridden noncooperative international equilibrium is jointly suboptimal behaviour of governments and firms is modelled as a three stage subgame perfect nash equilibrium the assumption that the government is the first player in this game allows it to influence equilibrium outcomes by altering the set of credible actions open to firms

aggregation and imperfect competition on the existence of equilibrium we present a new approach to the theory of imperfect competition and apply it to study price competition among differentiated products the central result provides general conditions under which there exists a pure strategy price equilibrium for any number of firms producing any set of products this includes products with multi dimen sional attributes in addition to the proof of existence we provide conditions for uniqueness our analysis covers location models the characteristics approach and probabilistic choice together in a unified framework to prove existence we employ aggregation theorems due to prekopa 1971 and borell 1975 our companion paper caplin and nalebuff 1991 introduces these theorems and develops the application to super majority voting rules we present a new approach to the theory of imperfect competition and apply it to study price competition among differentiated products the central result is that there exists a pure strategy price equilibrium for any number of firms producing any set of products in addition to the proof of existence we provide conditions for uniqueness our model both unites diverse strands of the earlier literature and opens up uncharted areas for future analysis in particular we expand the traditional one dimensional framework to allow for multi dimen sional product differentiation our approach involves twin restrictions on consumer preferences one on individuals preferences the other on the distribution of preferences across society these are generalizations of the restrictions supporting 64 majority rule presented in caplin and nalebuff 1988 to prove existence we apply a new technique of aggregation this technique is valuable in a variety of other problems in the companion paper we use the aggregation result to generalize our earlier work on 64 majority rule and to characterize the relationship between the distribution of human capital and the distribution of income caplin and nalebuff 1991 there are additional applications in statistics and in search theory we begin with a brief review of the early literature on imperfect competition describing in more detail the existence problem and previous solutions section 3 presents our twin assumptions and shows that they cover many standard cases in section 4 we introduce the aggregation theorem and use it in the analysis of demand functions the proof of existence of equilibrium is in section

strategic enhancement and destruction of fisheries and the environment in the presence of international externalities abstract this paper considers enhancement of fisheries and the environment in the presence of international externalities by enhancement we refer to investments which affect the costs and benefits of controlling fish harvest rates or pollution emission levels in a two country two period model it is shown that enhancement may be used strategically to influence the behavior of rival governments and that the strategic effect may either offset or reinforce the standard free rider problem associated with such investment in some cases countries may have an incentive to invest in environmental destruction i e negative enhancement if policies are not coordinated internationally

discrete modelling of supply response under uncertainty the case of the fishery abstract in the absence of complete control in a regulated industry effective management requires prediction of firms behavioral responses to public policy this paper develops a discrete choice model of supply response under uncertainty and applies it to fishery choice problems of new england fishing firms while fishermen demonstrate a bias towards remaining within the same fishery sufficient incentives in terms of changes in expected returns and risk are shown to elicit response due to extreme uncertainty concerning population dynamics of fish stocks a satisficing approach to management facilitated by this type of modelling may be more appropriate than bioeconomic optimization

a stochastic viability approach to ecosystem based fisheries management academia and management agencies show a growing interest for ecosystem based fishery management ebfm however the way to operationalize this approach remains challenging the present paper illustrates how the concepts of stochastic co viability which accounts for dynamic complexities uncertainties risk and sustainability constraints can be useful for the implementation of ebfm in the present case this concept is used to identify fishing strategies that satisfy both ecological conservation and economic sustainability in a multi species multi fleet context economic viability analysis eva and the broader co viability analysis cva are proposed to expand the usual population viability analysis pva and precautionary approach an illustration is proposed using data on the fisheries of bay of biscay france exploiting the stocks of nephrops and hake stochastic simulations show how cva can guarantee both ecological stock and economic profit sustainability using 2008 as a baseline the model is used to identify fishing efforts that ensure such co viability c 2012 elsevier b v all rights reserved

stability and success of regional fisheries management organizations according to international law straddling fish stocks should be managed cooperatively through regional fisheries management organizations rfmos this paper analyzes the stability and success of these organizations through a game in partition function form based on the classical gordon schaefer bioeconomic model results show that the larger the number of fishing states that compete for the fish stock the higher are the relative gains from full cooperation but the lower is the likelihood of large rfmos being stable it is also shown that new entrants increase the incentives of rfmo members to leave and decrease the incentives of non members to join it moreover the success of coalition formation is positively correlated with the degree of cost asymmetry among fishing states and negatively with the overall level of efficiency

the korean system of innovation and the semiconductor industry a governance perspective1 this paper explores in detail the political institutional processes and governance aspects of the korean system of innovation it shows i how the specific form of corporate governance chaebol evolved out of korea s national political institutional arrangements such as the state firm relationship based on reciprocal subsidy and ii how the dramatic emergence of korean semiconductor firms in world memory chip markets resulted from the subtle and changing interactions of state world market conditions and chaebol governance copyright 1998 by oxford university press

what is ecological economics ecological economics addresses the relationships between ecosystems and economic systems in the broadest sense these relationships are the locus of many of our most pressing current problems i e sustainability acid rain global warming species extinction wealth distribution but they are not well covered by any existing discipline environmental and resource economics as it is currently practiced covers only the application of neoclassical economics to environmental and resource problems ecology as it is cur rently practiced sometimes deals with human impacts on ecosystems but the more common tendency is to stick to natural systems ecological economics aims to extend these modest areas of overlap it will include neoclassical environmental economics and ecological impact studies as sub sets but will also encourage new ways of thinking about the linkages between ecological and economic systems we have chosen the name ecological economics for this area of study because it implies a broad ecological interdisciplinary and holistic view of the problem of studying and managing our world the earth from space cover of the journal reflects this global holistic perspective we did not intend to imply with the ordering of the two words in the title that the journal is mainly an economics journal it is intended to be a new approach to both ecology and economics that recognizes the need to make economics more cognizant of ecological impacts and dependencies the need to make ecology more sensitive to economic forces incentives and constraints and the need to treat integrated economic ecologic systems with a common but diverse set of conceptual and analytical tools there was much discussion of other possible names such as economic ecology or ecology and economics or some conjoining of the two words that to me end up being confusing tongue twisters like ecolnomics or econology but ecological economics seemed to get closest to the mean ing we desired while still being evocative to the uninitiated