threshold management in a coupled economic ecological system abstract economic analysis of optimal ecosystem management in the presence of a threshold has typically ignored the potential for induced behavioral responses this paper contributes to the literature on non convex ecosystem management by considering the implications of a particular behavioral response in a regional economy that of amenity led growth to changes in ecosystem services generated by a lake ecosystem subject to a eutrophication threshold the essential policy challenge is to achieve optimal levels of lake nutrients and urbanization given that improvements to water quality will induce additional migration and urbanization in the region with attendant ecological impacts we show that policies that ignore the recursive relationship between urbanization and water quality unintentionally exacerbate boom bust cycles of regional growth and decline and risk pushing the system towards long run economic decline in contrast the optimal policy accounts for the behavioral feedbacks to improved ecosystem services and balances regional growth and ecological degradation

a search cost model of obfuscation this article develops models in which obfuscation is individually rational for oligopolistic firms firms sell a homogeneous good to rational consumers who incur search costs to learn prices search costs are endogenized by allowing obfuscation firms have an unobservable action that increases the time needed to learn their price one model involves search costs convex in shopping time we show that slight convexity can dramatically alter the equilibrium price distribution a second model examines an informational linkage between current and future search costs consumers are uncertain about a component of search costs here a signal jamming mechanism can lead to equilibrium obfuscation

agent based computational transaction cost economics this article explores the use of agent based computational economics ace for modelling the development of transactions between firms transaction cost economics neglects learning and the development of trust ignores the complexity of multiple agents and assumes rather than investigates the efficiency of outcomes efficiency here refers to minimum cost or maximum profit we model how co operation and trust emerge and shift adaptively as relations evolve in a context of multiple interacting agents this may open up a new area of application for the ace methodology a simulation model is developed in which agents make and break transaction relations on the basis of preferences based on trust and potential profit profit is a function of product differentiation specificity of assets economy of scale and learning by doing in ongoing relations agents adapt their trust in a partner as a function of his loyalty exhibited by his continuation of a relation they also adapt the weight they attach to trust on the basis of realized profit the model enables an assessment of the efficiency of outcomes relative to the optimum as a function of trust and market conditions we conduct a few experiments to illustrate this application of ace

heuristic learning and the discovery of specialization and exchange abstract i develop and calibrate an agent based model of boundedly rational adaptive agents in a two good production and exchange economy to replicate human subject outcomes in the same eight person experimental economy to test agents ability to capture human behavior i extend the model and use its output to make predictions about a second experimental environment in which the group of eight agents is slowly constructed by merging smaller groups this environment improves human subject performance in the specialization and exchange task and commensurate improvement emerges for some parameterizations of the agent based model this iterative process yields incremental improvement of decision level theories about economic discovery

simple market equilibria with rationally inattentive consumers we study a market with rationally inattentive consumers who are unsure of the terms of the offers made by firms but can acquire information about the terms at a cost in a symmetric equilibrium the price set by firms is continuously increasing in the cost of information for consumers and decreasing in the number of firms operating in addition favorable a priori information about a firm leads it to set a higher price and a new entrant can increase demand for incumbents when consumers have heterogeneous costs of information firms selling low quality products may choose to set the highest prices

agency relationships in family firms theory and evidence does owner management necessarily eliminate the agency costs of ownership drawing on agency literature and on the economic theory of the household we argue that private ownership and owner management expose privately held owner managed firms to agency threats ignored by jensen s and meckling s 1976 agency model private ownership and owner management not only reduce the effectiveness of external control mechanisms they also expose firms to a self control problem created by incentives that cause owners to take actions which harm themselves as well as those around them jensen 1994 p 43 thus shareholders have incentive to invest resources in curbing both managerialand owner opportunism we extend this thesis to the domain of the family firm after developing hypotheses which describe how family dynamics and specifically altruism exacerbate agency problems experienced by these privately held owner managed firms we use data obtained from a large scale survey of family businesses to field test our hypotheses and find evidence which suggests support for our proposed theory finally we discuss the implications of our theory for research on family and other types of privately held owner managed firms

complexity and the character of stock returns empirical evidence and a model of asset prices based on complex investor learning empirical evidence on the distributional characteristics of common stock returns indicates 1 a power law tail index close to three describes the behavior of the positive tail of the survivor function of returns pr r x x a reflection of fat tails 2 general linear and nonlinear dependencies exist in the time series of returns 3 the time series return process is characterized by short run dependence short memory in both returns as well as their volatility the latter usually characterized in the form of autoregressive conditional heteroskedasticity and 4 the time series return process probably does not exhibit long memory but the squared returns process does exhibit long memory we propose a model of complex self referential learning and reasoning amongst economic agents that jointly produces security returns consistent with these general observed facts and which are supported here by empirical results presented for a benchmark sample of 50 stocks traded on the new york stock exchange the market we postulate is populated by traders who reason inductively while compressing information into a few fuzzy notions that they can in turn process and analyze with fuzzy logic we analyze the implications of such behavior for the returns on risky securities within the context of an artificial stock market model dynamic simulation experiments of the market are conducted from which market clearing prices emerge allowing us to then compute realized returns we test the effects of varying values of the parameters of the model on the character of the simulated returns the results indicate that the model proposed in this paper can jointly account for the presence of a power law characterization of the positive tail of the survivor function of returns with exponent on the order of three for autoregressive conditional heteroskedasticity for long memory in volatility and for general nonlinear dependencies in returns

willingness to pay for car safety evidence from sweden this study estimates a marginal willingness to pay wtp function for a road mortality risk reduction observed marginal wtp from the swedish car market is used and found to be positively correlated with the baseline risk of the cars no statistically significant relationships between examined owner attributes e g wealth and background risk and marginal wtp are found when comparing the estimated monetary value of a non marginal risk reduction derived from the integral of the marginal wtp function with an estimate based on marginal wtp we find in line with expectations that the difference between the estimates is negligible for smaller risk reductions and small 4 10 also for relatively large risk reductions

altruistic versus egoistic behavior in a public good game this paper analyzes an evolutionary version of the public good game in which boundedly rational agents can use imitation and best reply decision rules several possibilities for both decision rules to be present in the population are considered i show that altruistic behavior might survive if switching between the decision rules occurs less often than the probabilities of errors in choosing a strategy and if local neighborhoods are not too small or too large

rational behavior and economic theory abstract nowadays it seems almost universally presumed that the fundamental characteristic of homo oeconomicus is his rationality we analyze the role played by the concept of rationality in economic theory and demonstrate that it is necessarily constrained to be an essentially contentless notion we show that the main body of economic theory is firmly grounded and that some contrasting approaches to rationality although leading to heated debates and vivid confusion have no fundamental significance for economics with a refereshed view on the essence of economics we argue that the principles of economic theory form an essential methodological guide for the emergent line of research based on the use of so called evolutive models

reinforcement learning in the el farol model abstract the paper applies the approach of reinforcement learning to arthur s american economic review 84 1994a 406 el farol problem where repeatedly a population of agents decides to go to a bar or stay home and going is enjoyable if and only if the bar is not crowded the numerical simulations show that the learning process is fairly efficient in that attendances tend to fluctuate around the bar s capacity on the other hand the shape of the long run equilibrium frequency distribution is usually quite distinct from the nash equilibrium solutions and furthermore rather sensitive to some of the model s specification details

strategies and evolution in the minority game a multi round strategy experiment abstract minority games are a stylized description of strategic situations with both coordination and competition these games are widely studied using either simulations or laboratory experiments simulations can show the dynamics of aggregate behavior but the results of such simulations depend on the type of strategies used so far experiments provided little guidance on the type of strategies people use because the set of possible strategies is very large we therefore use a multi round strategy method experiment to directly elicit people s strategies between rounds participants can adjust their strategy and test the performance of possible new strategies against strategies from the previous round strategies gathered in the experiment are subjected to an evolutionary competition the strategies people use are very heterogeneous although aggregate outcomes resemble the symmetric nash equilibrium the strategies that survive evolutionary competition achieve much higher levels of coordination

introduction to the special issue on agent based computational economics abstract a brief overview of agent based computational economics ace is given followed by a synopsis of the articles included in this special issue on ace and in a companion special issue on ace scheduled to appear in computational economics

equilibrium and reinforcement learning in private information games an experimental study abstract this paper examines the abilities of standard game theoretic solution concepts static nash equilibrium and a simple model of individual learning to describe subject behavior in an experiment involving private information games with mixed strategy nash equilibrium outcomes the experimental data are compared in several ways with the predictions of static nash equilibrium and the quite different predictions of the learning model which is based on the models of roth and erev 1995 games and economic behavior special issue nobel symposium vol 8 pp 164 212 nash equilibrium does not adequately describe subject behavior whereas the learning model performs well in describing aspects of the evolution in behavior over time

knight on risk and uncertainty it is argued that the received interpretation of knight s classic riskuncertainty distinction as concerning whether or not agents have subjective probabilities constitutes a misreading of knight on the contrary knight shared the modern view that agents can be assumed always to act as if they have subjective probabilities we document our contention that by uncertainty knight instead meant situations in which insurance markets collapse because of moral hazard or adverse selection knight s discussion of market failure although always informal and in places inaccurate was in many respects a remarkable anticipation of the modern literature

learning by imitation abstract this paper introduces a learning algorithm that allows for imitation in recursive dynamic games the kiyotaki wright model of money is a well known example of such decision environments in this context learning by experience has been studied before here we introduce imitation as an additional channel for learning in numerical simulations we observe that the presence of imitation either speeds up social convergence to the theoretical markov nash equilibrium or leads every agent of the same type to the same mode of suboptimal behavior we observe an increase in the probability of convergence to equilibrium as the incentives for optimal play become more pronounced

how to decide when experts disagree uncertainty based choice rules in environmental policy environmental economists have traditionally addressed the issue of choice under uncertainty by applying the expected utility hypothesis when policymakers face a panel of experts with widely divergent beliefs the problem may more accurately be described as a case of choice under pure uncertainty arrow and hurwicz 1972 demonstrate that rational choice criteria under pure uncertainty will focus on the extremes of the state space not the midpoint as is typically assumed using nordhaus s dice model uncertainty based choices about global warming policies are evaluated linkages to the safe minimum standard and the precautionary principle are also discussed

local robustness analysis theory and application this paper develops a general framework for conducting local robustness analysis by local robustness we refer to the calculation of control solutions that are optimal against the least favorable model among models close to an initial baseline we provide nash and stackelberg equilibrium characterizations of the choice of control we apply this abstract formulation to a class of discrete time control problems this analysis is conducted using frequency domain methods and is shown to involve certain fundamental limits to the efficacy of controls in such environments finally we discuss some implications of our results for monetary policy

can neoclassical economics handle complexity the fallacy of the oil spot dynamic abstract this paper is essentially a rebuttal of the view that neoclassical economics can handle complexity i have coined the locution oil spot dynamic to denote the neoclassical ability to subsume each and every new perspective the main part of the paper is devoted to showing why the oil spot dynamic cannot work with the complexity approach which is seen as a coherent stand alone research program that stems from the sfi economics program and manifests itself with different nuances the fallacy of the oil spot dynamic is relevant in this period in which economists are beginning to realize that the neoclassical samuelsonian paradigm no longer represents the common language of their profession the spread of the complexity approach and the dissolving notion of mainstream are here interpreted as indicative of a changing economics a short foray into the features of the process of change completes my arguments by showing that the shift from one paradigm to another has many interrelated dimensions and that there may be rigidities internalizing changes

theories of choice under ignorance and uncertainty abstract in this paper knight s distinction between risk and uncertainty and its significance for economic analysis are examined the paper consists of a survey of some recent developments on the theory of choice under uncertainty and some applications of these theories to problems for which bayesian decision theory has not proved entirely satisfactory two problems are examined in detail the first is that of finance and insurance and the second is that of risktaking behaviour with special emphasis on lotteries

evolutionary dynamics in club goods binary games abstract a dynamic adjustment mechanism based on replicator dynamics in discrete time is used to study the time evolution of a population of players facing a binary choice game with social influence characterized by payoff curves that intersect at two interior points also denoted as thresholds so besides the boundary equilibria where all players make the same choice there are two further steady states where agents playing different strategies coexist and get identical payoffs such binary game can be interpreted as a club good game in which players have to choose either joining or not the club in the presence of cost sharing so that they can enjoy a good or a service provided that a participation threshold is reached at the same time congestion occurs beyond a second higher threshold these binary choice models can be used and indeed have been used in the literature to represent several social and economic decisions such as technology adoption joining a commercial club r d investments production delocalization programs for environmental protection existence and stability of equilibrium points are studied as well as the creation of more complex attractors periodic or chaotic related with overshooting effects the study of some local and global dynamic properties of the evolutionary model proposed reveals that the presence of the participation threshold causes the creation of complex topological structures of the basins of coexisting attracting sets so that a strong path dependence is observed the dynamic effects of memory both in the form of convex combination of a finite number of previous observation moving average and in the form of memory with increasing length and exponentially fading weights are investigated as well

appropriative water rights and the efficient allocation of resources this paper investigates the allocative efficiency of the appropriative system of water rights within the context of a simplified model of a water using industry at a long run competitive equilibrium for the industry and with a prohibition on the transfer of water rights among firms it is shown that 1 senior appropriators claim and use more water than junior appropriators 2 senior appropriators bear less risk than junior appropriators 3 the allocation of water and diversion capacitie 6among firms is inefficient being dominated by an equal sharing among firms the equal sharing allocation which is pareto optimal when diversion capacities are supplied by a competitive leasing industry can be achieved under the appropriative system if there are competitive markets in water rights and in leases for the use of diversion capacities an application of the coase theorem

a folk theorem for minority games we study a particular case of repeated games with public signals in the stage game an odd number of players have to choose simultaneously one of two rooms the players who choose the less crowded room receive a reward of one euro whence the name minority game the players in the same room do not recognize each other and between the stages only the current majority room is publicly announced we show that in the infinitely repeated game any feasible payoff can be achieved as a uniform equilibrium payoff and as an almost sure equilibrium payoff in particular we construct an inefficient equilibrium where with probability one all players choose the same room at almost all stages this equilibrium is sustained by punishment phases which use in an unusual way the pure actions that were played before the start of the punishment

self efficacy beliefs and imitation a two armed bandit experiment abstract it is generally believed that individuals imitate others to gain status minimise regret or simply ameliorate their performance psychology provides a complementary explanation imitation becomes appealing when agents have little faith in their abilities we investigate the extent to which self efficacy beliefs affect agents propensities to imitate others we propose an experimental task which is a modified version of the two armed bandit we measure participants self assessed self efficacy then study individual learning subsequently we measure how individuals use the information they gather observing a randomly selected group leader we find that in stable environments a 1 increase in individual self efficacy reduces the propensity to imitate others by 3

globalizing carbon lock in this paper extends the arguments surrounding carbon lock in elaborated in unruh energy policy 28 2000 817 30 2002 317 to countries currently undergoing industrialization it argues that for numerous reasons industrializing countries are unlikely to leapfrog carbon intensive energy development on the contrary carbon lock in may be globalizing and could further constrain climate change mitigation options it is then argued that many policy recommendations ignore carbon lock in possibly limiting their potential for successful implementation the paper then discusses four policy approaches that appear to have advantages given lock in conditions it is recognized however that relative ease of implementation does not necessarily equate with superiority instead it is merely a path dependent outcome of past development decisions pursuing policies on the basis of relative implementation ease may help address the issue of climate change but could also result in sub optimal outcomes along other dimensions of sustainable development

competition for attention we present a model of market competition in which consumers attention is drawn to the products most salient attributes firms compete for consumer attention via their choices of quality and price strategic positioning of a product affects how all other products are perceived with this attention externality depending on the cost of producing quality some markets exhibit commoditized price salient equilibria while others exhibit de commoditized quality salient equilibria when the costs of quality change innovation can lead to radical shifts in markets as in the case of decommoditization of the coffee market by starbucks in the context of financial innovation the model generates the phenomenon of reaching for yield

markets for water rights under environmental constraints abstract the cumulative impact of pollutants on water quality at a given location along a river is a function of prior loadings as well as pollution and surface flows at that particular site the question of whether it is possible to maintain water quality under alternative mechanisms for allocating surface water and pollution rights is addressed we model the optimal allocation of surface water and pollution rights along a river with water quality constraints due to cumulative effects the shadow values of water and pollution rights are contingent on location it is shown that a nash equilibrium in a market for tradable surface water rights in conjunction with a market for pollution damages implements the optimal solution the market supports location specific prices for both consumptive water rights and pollution damages

a global game with strategic substitutes and complements abstract we study a global game in which actions are strategic complements over some region and strategic substitutes over another region an agent s payoff depends on a market fundamental and the actions of other agents if the degree of congestion is sufficiently large agents strategies are non monotonic in their signal about the market fundamental in this case a signal that makes them believe that the market fundamental is more favorable for an action may make them less likely to take the action because of the risk of overcrowding

genetic algorithm learning and the cobweb model this paper presents the cobweb model in which competitive firms in a market for a single good use a genetic algorithm to update their decision rules about next period production and sales the results of simulations show that the genetic algorithm converges to the rational expectations equilibrium for a wider range of parameter values than other algorithms frequently studied within the context of the cobweb model price and quantity patterns generated by the genetic algorithm are also compared to the data of experimental cobweb economies it is shown that the algorithm can capture several features of the experimental behavior of human subjects better than three other learning algorithms that are considered

allocating resources in an uncertain world water management and endangered species instream flows may be essential in protecting aquatic species that are threatened or endangered an economic model of the optimal allocation of water under pure uncertainty is developed with particular attention paid to the situation when a species characterized by critical depensation is affected by instream flows we adopt the notion of pure uncertainty that frank knight and daniel ellsberg intended which applies when decision makers cannot reduce their uncertainty to a unique probability distribution following recent work by hansen sargent and others we employ robust control as a way to deal with this problem copyright 2008 oxford university press

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

living in an imaginary world that looks real abstract in the paper we show using standard approaches general equilibrium modeling and the assumption of complete rationality that the macroeconomic environment is endogenous and is indeterminate specifically it is argued without resorting to sunspot type arguments that microeconomic fundamentals do not suffice to characterize the economy at the macro level in particular we show how perceptions of rational agents of the workings of the economy a shape the environment b affect the environment sufficiently to ensure that rational economic agents find the observed environment consistent with their beliefs even though it is not as a by product we illustrate that endogenous macro uncertainty can arise as an outcome if rational economic agents whose expectations are anchored on endogenous variables expect them to arise finally we show that systematic errors can persist indefinitely under rationality

inter pattern speculation beyond minority majority and games abstract a new simple model of financial market is proposed based on the sequential and inter temporal nature of trader trader interaction and on a new simple trading strategy space in this pattern based speculation model the traders open hold and close their positions explicitly information ecology is strikingly similar to that of the minority game which suggest to reinterpret the latter as a model of synchronisation of predictability exploitation naive and sophisticated agents are shown to give rise to very different phenomenology

fishery management under multiple uncertainty abstract among others who point to environmental variability and managerial uncertainty as causes of fishery collapse roughgarden and smith proc natl acad sci 93 1996 5078 argue that three sources of uncertainty are important for fisheries management variability in fish dynamics inaccurate stock size estimates and inaccurate implementation of harvest quotas we develop a bioeconomic model with these three sources of uncertainty and solve for optimal escapement based on measurements of fish stock in a discrete time model among other results we find 1 when uncertainties are high we generally reject the constant escapement rule advocated in much of the existing literature 2 inaccurate stock estimation affects policy in a fundamentally different way than the other sources of uncertainty and 3 the optimal policy leads to significantly higher commercial profits and lower extinction risk than the optimal constant escapement policy by 42 and 56 respectively

a natural experiment approach to contingent valuation of private and public uv health risk reduction strategies in low and high risk countries we present the results of a natural experiment to test how variations in exogenous risk levels affect resultant willingness to pay wtp for risk reduction the case study presented considers wtp for reductions in the skin cancer risks associated with exposure to solar uv radiation a common design contingent valuation survey is conducted in four countries across which variation in geographical latitude and genetic mix mean that exogenous risks differ substantially survey respondents were presented with both a private and public good route for affecting risk reduction in both cases results confirm that once adjustment had been made for expected relationships with other covariates such as income and risk averting behaviour valuation responses for both goods conformed to expectations with the ordering of values across countries reflecting the ordering of scientifically established health risks this suggests that links between values and objective health risks may be observed within such situations and provides a justification for continuing research into more natural representations of risk and risk reductions in order to yield consistent and robust measures of associated values

adaptive consumption behavior abstract in this paper we propose and study a theory of adaptive consumption behavior under income uncertainty and liquidity constraints we assume that consumption is governed by a linear function of wealth whose coefficients are revised each period by a procedure that places few informational or computational demands on the consumer we show that under a variety of settings the procedure converges quickly to a set of coefficients with low welfare cost relative to a fully optimal nonlinear consumption function

political economy based institutional industry complex and sustainable development the case of the salt chemical industry in huai an china abstract this article explains how the salt chemical industry may evolve over time from a high energy consumption based industry complex in the local community to a consolidated pro growth pluralist regime at the urban scale the salt chemical industry is resisting to restructure to a sustainable environmental friendly economic system by spilling over in the form of pro growth political economic coalition in local society theories of the logan and molotch s growth machine stone s urban regime together with the extension of unruh s thesis concerning the characteristics of lock in in the technological or institutional economics approach were used to propose an enlarged lock in political economic framework and pro growth institutional industry complex iic it is further used to explain the consensus building of the pro growth governance a study of the salt chemical and new material industry park in the huai an metropolitan area china serves as an illustrative case the article also suggests that the path dependence followed in constructing a pro growth coalition could serve as a program to unlock the pro growth institutional industry complex of salt chemical industry and foster the anti coalition needed

acquisition of costly information an experimental study abstract i study decision making in a situation where subjects can buy information in order to uncover the initially unknown deterministic structure the majority of subjects fail to find the most economical way of choosing between two possible prospects many subjects underestimate the value of information and as a result make avoidable forecasting errors other subjects learn correctly which action is most successful under any given condition but fail to implement this knowledge efficiently they either accept errors for the sake of economizing on small amounts of information costs or they invest in redundant information the measured losses are substantial however in certain settings the fact that half of the economist subjects and one fourth of non economist subjects learn to behave optimally may be sufficient for efficient market functioning the present findings thus help to explain the near competitive outcomes observed in many experimental and actual markets

harvesting a renewable resource under uncertainty abstract this paper presents a theory of harvesting that allows for partial harvests and accounts for the risk of extinction for biological assets with size dependent stochastic growth the harvesting decision is formulated as a disinvestment problem in continuous time and generalized faustmann formulas are derived the probability of extinction is then analyzed for a wide class of growth functions an illustration based on the logistic brownian motion shows that both optimal biomass at harvest and harvest size do not vary monotonically with uncertainty more generally this paper illustrates the importance of properly accounting for barriers in stochastic investment problems

a learning to forecast experiment on the foreign exchange market with a classifier system abstract this paper reports on an experiment of learning and forecasting on the foreign exchange market by means of an artificial intelligence methodology a classifier system which simulates learning and adaptation in complex and changing environments the experiment has been run for two different exchange rates the us dollar d mark rate and the us dollar yen rate representative of two possibly different market environments a fictitious artificial agent is first trained on a monthly data base from 1973 to 1990 and then tested out of sample from 1990 to 1992 its forecasting performance is then compared with the performance of decision rules which follow the prescription of various economic theories on exchange rate behaviour and the performance of forecasts given by var estimations of the exchange rate s determinants

how vulnerable is the emissions market to transaction costs an abms approach abstract the impact of transaction costs on the early emissions trading market is examined by applying an agent based model and simulation abms approach for a realistic model set up bounded rationality stochastic characteristics and learning by doing are considered in our search processes marginal abatement cost parameters are obtained from yoo et al 2010 which is an experimental study on the emissions trading in the korean power sector sensitivity analyses are performed on market performance indices with regard to transaction cost parameters which represent scales and the learning elasticities of transaction costs a total of 960 simulations were run in this sensitivity analysis sensitivity analysis results consistently show that higher transaction costs worsen market performance the most remarkable finding in these results is that welfare performance of all the transactions decreases by up to 50 as the scale parameters of transaction costs increase implying that welfare gain from introducing emissions trading disappears significantly however with learning curve effect welfare performance could be regained by up to 26 in sum although transaction costs significantly encroach upon trade gains at the early stage based on our simulation results the welfare loss by way of transaction costs is lessened as the knowledge of market participants progresses

the role of regulatory learning in energy transition the case of solar pv in brazil abstract an important problem that has attracted significant amount of attention within the context of energy transitions is the carbon lock in a situation in which energy systems are locked in to high carbon technologies through a path dependent process several measures to avoid the carbon lock in involve technology specific measures which in turn implies that those measures may result in an energy system locked in to certain low carbon technologies we consider that the brazilian system needs policies to escape the carbon lock in which are based on providing incentives to low carbon technologies we develop an analytical framework to analyze the role of regulatory institutions in the possible lock in to utility scale photovoltaic in the sense that they create barriers to the adoption of distributed generation photovoltaic we show that the definition of a process to adapt the institutional framework in a context of stress in the innovation system is crucial for the adoption of new technologies applying our framework to the brazilian power sector we observe that only when regulators consider the possibility that the system is locked in to centralized production technologies and not when they just consider the carbon lock in they manage to eliminate barriers to distributed generation based on solar pv

coordination through social learning in a general equilibrium model this paper analyses coordination through social learning in a general equilibrium model we use a fully decentralized economy in which households and firms exchange labour and consumption goods in the corresponding markets with potential rationing their strategies are updated through an evolutionary learning process based on imitation and random experimenting this learning process induces substantial coordination failures especially between firms which lead almost systematically to below equilibrium output levels and social welfare losses the main underlying mechanism is a self reinforcing uneven distribution of households income which results in a lack of aggregate demand

expectational diversity in monetary economies abstract we investigate an overlapping generations monetary economy in which expectations depend upon backward looking predictors of the future price level we use discrete choice theory to model how agents select a predictor based on its past forecast error letting the number of available predictors tend to infinity we obtain the large type limit of the system taking the large type limit dramatically reduces the number of free parameters while maintaining the expectational diversity which we argue is necessary for constructing plausible learning based models the model s dynamics are strongly influenced by the intensity of choice which measures how sensitive an agent s predictor choice is to differences in forecast errors across predictors when the intensity of choice is low the monetary steady state is stable as the intensity of choice increases and if certain parametric restrictions are met the system undergoes a hopf bifurcation in which case we document the existence of highly irregular equilibrium price paths

harvest decisions and asset valuation for biological resources exhibiting size dependent stochastic growth optimal harvest rules and preharvest valuation procedures are derived for biological assets with stochastic size dependent growth in a stochastic price environment these issues are analyzed as continuous time optimal stopping problems both the single rotation and ongoing rotations problems are addressed the sensitivity of harvest and valuation rules is assessed the results are compared with those derived from a myopic look ahead procedure and with the corresponding findings for age dependent growth copyright 1990 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

fuzzy inductive reasoning expectation formation and the behavior of security prices abstract this paper extends the santa fe artificial stock market model sfasm studied by lebaron arthur and palmer 1999 journal of economic dynamics and control 23 1487 1516 in two important directions first some might question whether it is reasonable to assume that traders are capable of handling a large number of rules each with numerous conditions as is assumed in the sfasm we demonstrate that similar results can be obtained even after severely limiting the reasoning process we show this by allowing agents the ability to compress information into a few fuzzy notions which they can in turn process and analyze with fuzzy logic second lebaron et al have reported that the kurtosis of their simulated stock returns is too small as compared to real data we demonstrate that with a minor modification to how traders go about deciding which of their prediction rules to rely on when making demand decisions the model can in fact produce return kurtosis that is comparable to that of actual returns data

self organized criticality in a dynamic game we investigate conditions under which self organized criticality soc arises in a version of a dynamic entry game in the simplest version of the game there is a single location a pool and one agent is exogenously dropped into the pool every period payoffs to entrants are positive as long as the number of agents in the pool is below a critical level if an agent chooses to exit he cannot re enter resulting in a future payoff of zero agents in the pool decide simultaneously each period whether to stay in or not we characterize the symmetric mixed strategy equilibrium of the resulting dynamic game we then introduce local interactions between agents that occupy neighboring pools and demonstrate that under our payoff structure local interaction effects are necessary and sufficient for soc and for an associated power law to emerge thus we provide an explicit game theoretic model of the mechanism through which soc can arise in a social context with forward looking agents

allocative efficiency of markets with zero intelligence traders market as a partial substitute for individual rationality we report market experiments in which human traders are replaced by zero intelligence programs that submit random bids and offers imposing a budget constraint i e not permitting traders to sell below their costs or buy above their values is sufficient to raise the allocative efficiency of these auctions close to 100 percent allocative efficiency of a double auction derives largely from its structure independent of traders motivation intelligence or learning adam smith s invisible hand may be more powerful than some may have thought it can generate aggregate rationality not only from individual rationality but also from individual irrationality

uncertain health and survival effects on end of life consumption this article analyzes the impact of health and survival uncertainty on the saving and consumption decisions of retirees a dynamic programming approach is used to model the household s planning problem the utility parameters are estimated using panel data we find that a fall into poor health raises the marginal utility from consumption simulations are used to indicate the effects of falling into poor health and loss of spouse they reveal a large transfer from the healthy to the sick partner and a strong dependence of saving on the survivor benefits suggesting that concern about the surviving spouse is an important motive for saving

learning about learning in games through experimental control of strategic interdependence we report experiments in which humans repeatedly play one of two games against a computer program that follows either a reinforcement learning or an experience weighted attraction algorithm our experiments show these learning algorithms detect exploitable opportunities more sensitively than humans also learning algorithms respond to detected payo increasing opportunities systematically however the responses are too weak to improve the algorithms payos human play against various decision maker types doesn t vary signicantly these factors lead to a strong linear relationship between the humans and algorithms action choice proportions that is suggestive of the algorithm s best response correspondence these properties are revealed only by our human versus computer experiments and not by our standard human versus human experiments nor our model simulations jel classication c72 c92 c81

rigid pricing and rationally inattentive consumer abstract this paper proposes a mechanism leading to rigid pricing as an optimal strategy it applies a framework of rational inattention to study the pricing strategies of a monopolistic seller facing a consumer with limited information capacity the consumer needs to process information about the realized price while the seller is perfectly attentive the seller chooses to price rigidly i e prices respond to changes in the unit input cost less than if the consumer was perfectly attentive the rigidity is sometimes manifested by discreteness of prices the seller charges a finite set of different prices even for a continuous range of unit input costs the seller does so to provide the consumer with easily observable prices which stimulates her to consume more and increases the seller s profit

genetic algorithms and inflationary economies abstract this paper studies overlapping generations economies in which agents use genetic algorithms to learn correct decision rules the results of computer simulations show that a genetic algorithm converges to the unique monetary steady state in case of a constant money supply policy and to the low inflation stationary equilibrium in case of a constant real deficit financed through seignorage features of the genetic algorithm adaptation are compared to the performance of other learning algorithms and to the behavior observed in experiments with human subjects in the same olg environments

multi agent simulations to explore rules for rural credit in a highland farming community of northern thailand thanks to recent advances in the field of distributed artificial intelligence agentbased models abm can now be used to run simulations of social phenomena based on their computerized representations and to apply experimental methods in social sciences axelrod 1997 gilbert and troitzsch 1999 jager 2000 in the field of renewable resource management and environmental sciences several abm simulation platforms offer the possibility to explore interactions between social and ecological dynamics costanza and ruth 1998 bousquet et al 1998 lansing 2002 in these complex systems the social and economic dynamics can be viewed as a set of interactions among heterogeneous agents generating aggregate phenomena that are different from the behaviour of groups of average individuals considered in classical economic thinking rouchier and bousquet 1998 such a view was adopted in the research presented here

crises and confidence systemic banking crises and depositor behavior abstract we show that individuals who have experienced a systemic banking crisis are 11 percentage points less likely to use banks in the u s than otherwise similar individuals who emigrated from the same country but did not live through a crisis this finding is robust to controlling for exposure to other macroeconomic events and to various methods for addressing potential bias due to migrant self selection consistent with the view that personal experience plays an important role in decision making the effects are larger for individuals who were older and more likely to have had wealth entrusted to the banking system at the time of the crisis and for people who experienced crises in countries without deposit insurance

rationalizability learning and equilibrium in games with strategic complementarities we study a rich class of noncooperative games that includes models of oligopoly competition macroeconomic coordination failures arms races bank runs technology adoption and diffusion r d competition pretrial bargaining coordination in teams and many others for all these games the sets of pure strategy nash equilibria correlated equilibria and rationalizable strategies have identical bounds also for a class of models of dynamic adaptive choice behavior that encompasses both best response dynamics and bayesian learning the players choices lie eventually within the same bounds these bounds are shown to vary monotonically with certain exogenous parameters we study the class of noncooperative supermodular games introduced by topkis 1979 and further analyzed by vives 1985 1989 who also pointed out the importance of these games in industrial economics supermodular games are games in which each player s strategy set is partially ordered the marginal returns to increasing one s strategy rise with increases in the competitors strategies so that the game exhibits strategic complementarity 2 and if a player s strategies are multidimensional marginal returns to any one com ponent of the player s strategy rise with increases in the other components this class turns out to encompass many of the most important economic applications of noncooperative game theory in macroeconomics diamond s 1982 search model and bryant s 1983 1984 rational expectations models can be represented as supermodular games in each of these models more activity by some members of the economy raises the returns to increased levels of activity by others in oligopoly theory some models of bertrand oligopoly with differentiated products qualify as supermodu lar games in these games when a firm s competitors raise their prices the marginal profitability of the firm s own price increase rises a similar structure is present in games of new technology adoption such as those of dybvig and spatt 1983 farrell and saloner 1986 and katz and shapiro 1986 when more users hook into a communication system or more manufacturers adopt an interface standard the marginal return to others of doing the same often rises similarly in some specifications of the bank runs model introduced by diamond and dybvig 1983 when more depositors withdraw their funds from a bank it is more worthwhile for other depositors to do the same in the warrant exercise

learning with fixed rules the minority game abstract this paper gives a critical account of the literature on adaptive behaviour in the minority game a simple congestion game the literature has proposed a model which differs markedly from many standard learning models in that players are endowed with a fixed subset of behavioural rules or response modes which map the observed history to actions these rules need not have a behavioural interpretation or be derived from some form of optimizing behaviour nonetheless this model gives rise to behaviour that is close to equilibrium behaviour at the aggregate level the individual level behaviour predicted by the model seems to capture some aspects of observed experimental behaviour that are difficult to explain using standard models

optimal sticky prices under rational inattention this paper presents a model in which price setting firms decide what to pay attention to subject to a constraint on information flow when idiosyncratic conditions are more variable or more important than aggregate conditions firms pay more attention to idiosyncratic conditions than to aggregate conditions when we calibrate the model to match the large average absolute size of price changes observed in micro data prices react fast and by large amounts to idiosyncratic shocks but only slowly and by small amounts to nominal shocks nominal shocks have strong and persistent real effects we use the model to investigate how the optimal allocation of attention and the dynamics of prices depend on the firms environment jel e 3 e5 d8

does volatility matter expectations of price return and variability in an asset pricing experiment abstract we present results of an experiment on expectation formation in an asset market participants in our experiment must provide forecasts of the stock future return to computerized utility maximizing investors and are rewarded according to how well their forecasts perform in the market in the baseline treatment participants must forecast the stock return one period ahead in the volatility treatment we also elicit subjective confidence intervals of forecasts which we take as a measure of perceived volatility the realized asset price is derived from a walrasian market equilibrium equation with non linear feedback from individual forecasts our experimental markets exhibit high volatility fat tails and other properties typical of real financial data eliciting confidence intervals for predictions has the effect of reducing price fluctuations and increasing subjects coordination on a common prediction strategy

logit ces and rational inattention abstract we study the fundamental links between two popular approaches to consumer choice the multinomial logit model of individual discrete choice and the ces utility function which describes a diversified choice of a representative consumer we base our analysis on the rational inattention ri model and show that the demand system of ri agents each of which chooses a single option coincides with the demand system of a fictitious representative agent with ces utility function thus the diversified choice of the representative agent may be explained by the heterogeneity in signals received by the ri agents we obtain a new interpretation for the elasticity of substitution and the weighting coefficients of the ces utility function specifically we provide a correspondence between parameters of the ces utility function prior knowledge and marginal cost of information

implications of rational inattention abstract a constraint that actions can depend on observations only through a communication channel with finite shannon capacity is shown to be able to play a role very similar to that of a signal extraction problem or an adjustment cost in standard control problems the resulting theory looks enough like familiar dynamic rational expectations theories to suggest that it might be useful and practical while the implications for policy are different enough to be interesting

the reality game abstract we introduce an evolutionary game with feedback between perception and reality which we call the reality game it is a game of chance in which the probabilities for different objective outcomes e g heads or tails in a coin toss depend on the amount wagered on those outcomes by varying the reality map which relates the amount wagered to the probability of the outcome it is possible to move continuously from a purely objective game in which probabilities have no dependence on wagers to a purely subjective game in which probabilities equal the amount wagered we study self reinforcing games in which betting more on an outcome increases its odds and self defeating games in which the opposite is true this is investigated in and out of equilibrium with and without rational players and both numerically and analytically we introduce a method of measuring the inefficiency of the game similar to measuring the magnitude of the arbitrage opportunities in a financial market we prove that the inefficiency converges to equilibrium as a power law with an extremely slow rate of convergence the more subjective the game the slower the convergence

the achilles heel of salience theory and a way to fix it abstract salience theory has been successfully used to explain a wide range of empirical and experimental phenomena such as the allais paradox framing effect the preference reversal phenomenon or the decoy and compromise effects in this paper we show that salience theory carries a notable flaw and under certain circumstances it suggests that a salient thinker may prefer a dominated option even when a strictly dominant alternative is available to her to solve this problem we propose a possible alteration of the theory and show how it accounts for the same phenomena as the salience theory

strategic pricing with rational inattention to quality this paper studies both theoretically and experimentally the pricing strategy of a rm that faces a consumer who is rationally inattentive to product quality sims 2003 in a standard sequential pricing game rational inattention to quality produces two types of mixed strategy perfect bayesian equilibria one where sellers pool at a low price and buyers are fully inattentive to quality and one where there is semi pooling at a high price and buyers are selectively attentive to quality i characterize these

behavioral heuristics and market patterns in a bertrand edgeworth game abstract this paper studies bertrand price setting behavior when firms face capacity constraints bertrand edgeworth game this game is known to lack equilibria in pure strategies while the mixed strategy equilibria are hard to characterize we explore families of heuristic rules for individual price setting behavior and the resulting market patterns through simulations of agent based models and laboratory experiments overall the individual pricing strategies observed experimentally can be represented approximately by a sales based simple rule in the experiments average market prices tend to converge from above and approach a state resembling a steady state with slow aggregate price variations and low price dispersion around an average near the competitive level however that configuration can be disturbed occasionally by excursions triggered by discrete price raises of some agents salient features of experimental results can be described by simulations where agents use sales based heuristics with parameters calibrated from the experiments the results obtained here suggest the existence of useful complementarities between analytical experimental and agent based simulation approaches

attention discrimination theory and field experiments with monitoring information acquisition we link two important ideas attention is scarce and lack of information about an individual drives discrimination in selection decisions our model of allocation of costly attention implies that applicants from negatively stereotyped groups face attention discrimination less attention in highly selective cherry picking markets where more attention helps applicants and more attention in lemon dropping markets where it harms them to test the prediction we integrate tools to monitor information acquisition into correspondence field experiments in both countries we study we find that unfavorable signals minority names or unemployment systematically reduce employers efforts to inspect resumes also consistent with the model in the rental housing market which is much less selective than labor markets we find landlords acquire more information about minority relative to majority applicants we discuss implications of endogenous attention for magnitude and persistence of discrimination in selection decisions returns to human capital and potentially for policy