nash cournot or lindahl behavior an empirical test for the nato allies this paper derives systems of demand equations for distinguishing between nash cournot and lindahl behavior in a group that either shares a pure public good or an activity that provides a private and a pure public joint product systems of simultaneous equations are estimated based upon nash cournot and lindahl behavior for a sample of ten nato allies for the 1956 1987 period nonnested hypothesis tests support the nash cournot specification for five of the ten sample allies no evidence of lindahl behavior is found the nash cournot joint product specification outperforms the pure public model for all sample allies

changing threat perceptions and the efficient provisioning of international security this paper proposes a mechanism for structuring international institutions to efficiently provision global security against the threat of a rogue nation the effects of security effort by an alliance member are assumed to be non rival and non excludable for other members specifically this effort has both positive and negative effects as security measures prevent attacks by the rogue nation but also involves loss of commercial and diplomatic benefits further the alliance members are assumed to have heterogeneous tastes regarding the desired security level the allies act strategically vis a vis one another with regard to security provision and the alliance a whole acts strategically with respect to the rogue nation which strategizes in turn importantly this paper investigates how the evolution of public opinion in the respective countries facing the rogue nation s threat impacts the proposed mechanism

oligopoly game price makers meet price takers abstract the paper studies an oligopoly game where firms can choose between price taking and price making strategies on a mixed market price takers are always better off than price makers though the profits of both types decline in the number of price takers we investigate and confront two possibilities of firms decisions about their types forward looking equilibrium reasoning and backward looking individual learning we find that the cournot outcome is the only equilibrium prediction and it is learnable if firms are sufficiently sensitive to profit differences however with a larger number of firms a unilateral deviation from cournot behavior becomes profitable under learning this incentive creates a space for permanent oscillations over different markets with a positive but low number of price takers

the strategic advantage of being less skilled abstract ability need not pay if public goods are financed by voluntary contributions this result first shown for exogenously given income is reinforced if income is endogenously generated in equilibrium welfare of complete free riders is ranked according to their wage rate whereas for contributors a higher productivity is disadvantageous furthermore it can be shown that the set of contributors consists of the skilled agents and only the less productive will act as complete free riders this results in a strong incentive for being less skilled

artificial adaptive agents in economic theory economic analysis has largely avoided questions about the way in which economic agents make choices when confronted by a perpetually novel and evolving world as a result there are outstanding questions of great interest to economics in areas ranging from technological innovation to strategic learning in games this is so despite the importance of the questions because standard tools and formal models are ill tuned for answering such questions however recent advances in computer based modeling techniques and in the subdiscipline of artificial intelligence called machine learning offer new possibilities artificial adaptive agents aaa can be defined and can be tested in a wide variety of artificial worlds that evolve over extended periods of time the resulting complex adaptive systems can be examined both computationally and analytically offering new ways of experimenting with and theorizing about adaptive economic agents many economic systems can be classified as complex adaptive systems such a system is complex in a special sense i it consists of a network of interacting agents processes elements ii it exhibits a dynamic aggregate behavior that emerges from the individual activities of the agents and iii its aggregate behavior can be described without a detailed knowledge of the behavior of the individual agents an agent in such a system is adaptive if it satisfies an additional pair of criteria the actions of the agent in its environment can be assigned a value performance utility payoff fitness or the like and the agent behaves so as to increase this value over time a complex adaptive system then is a complex system containing adaptive agents networked so that the environment of each adaptive agent includes other agents in the system complex adaptive systems usually operate far from a global optimum or attractor such systems exhibit many levels of aggregation organization and interaction each level having its own time scale and characteristic behavior any given level can usually be described in terms of local niches that can be exploited by particular adaptations the niches are various so it is rare that any given agent can exploit all of them as rare as finding a universal competitor in a tropical forest moreover niches are continually created by new adaptations it is because of this ongoing evolution of the niches and the perpetual novelty that results that the system operates far from any global attractor improvements are always possible and indeed occur regularly the everexpanding range of technologies and products in an economy or the everimproving strategies in a game like chess provide familiar examples adaptive systems may settle down temporarily at a local optimum where performance is good in a comparative sense but they are usually uninteresting if they remain at that optimum for an extended period a theory of complex adaptive systems based on aaa makes possible the development of well defined yet flexible models that exhibit emergent behavior such models can capture a wide range of economic phenomena precisely even though the development of a general mathematical theory of complex adaptive systems is still in its early stages the aaa models complement current theoretical directions they are

the theory of public goods non nash behaviour abstract most treatments of equilibrium public goods provision assume zero conjectural variations in the sense that each individual regards the behaviour of the rest of the community as independent of his own this paper introduces nonzero conjectural variations into the model a diagram is introduced which can depict both the individual s and the community s equilibrium in the presence of nonzero conjectural variations equilibrium and optimal outcomes are compared and a specific functional form is used to investigate the effect of community size on the nature of equilibrium finally we discuss the requirement that conjectures should be consistent

alternative models of spatial competition the concept of a spatial price equilibrium underlies most studies of spatial movement and competition however this concept is based upon a notion of perfectly competitive markets that is often unrealistic for many markets such as the markets for oil and coal and ignores the existence of local spatial monopolies this paper presents alternative economic models of spatial competition and shows how all of these models can be solved with essentially the same solution algorithm specifically after reformulating the classical spatial price equilibrium model and two extensions of takayama and judge s monopoly model we state and analyze a cournot nash model and discuss solution algorithms we then generalize these models and algorithms to multiple commodities and networks with transshipment nodes we conclude with a brief discussion of possible extensions of this class of models and associated algorithms

heterogeneous expectations adaptive learning and evolutionary dynamics this paper presents a linear self referential macroeconomic model with the possibility of multiple equilibria where agents have the choice of using one of two forecasting models one of minimum state variable form and the other of sunspot form to form expectations of current and future prices endogenous predictor selection is modeled as an evolutionary game where individuals choose among the forecasting models based on relative performance some nash solutions are not relevant as they are not stable under evolutionary or adaptive learning finally it is shown that the sunspot equilibrium is fragile against temporary shocks to information costs

gorman and musgrave are dual an antipodean theorem on public goods abstract this paper examines the conditions under which the allocation branch of the government can determine the optimum provision of public goods independently of the distribution of private goods we draw attention to the duality with the literature on aggregation over consumers private goods economies

understanding the health and nutritional status of children in ghana abstract the data set of the ghana living standards survey glss round 1 1987 1988 was utilized to analyse the principal determinants publicly and privately of health and nutrition of children under five in ghana while in most health and nutrition studies the emphasis is either on health related factors such as occurrence of illness immunization accessibility to light electricity the role of breastfeeding or on food availability and food consumption related factors in the present study an attempt has been made to incorporate both aspects simultaneously on the basis of the glss ghanaian households spend at the average approximately 60 of total expenses on food changes in relative prices of the various food commodities differently affect household food availability lowering prices of relatively cheap foods e g millet cassava tends to have a strong positive effect on total household kcal availability at the level of the household the absolute number of nondependents presumed to represent the available labour force is positively correlated with household food availability there is also a positive correlation between the mothers level of education 10 yrs of schooling and above and the nutrition level of children occurrence of illness in children could be shown to negatively affect their health and nutrition status finally a specific finding in the analysis was a rather strong negative effect of prolonged breastfeeding on the nutritional status of children among the policy recommendations emanating from the research are 1 promotion of efficient production and marketing of cassava 2 efforts to achieve slowing down of rural urban migration to prevent labour shortages in rural households 3 improving water and sanitation conditions 4 expanding immunization programmes in particular in rural areas and 5 promoting better weaning practices when children are no longer fully breastfed

spatial market policy modeling with goal targets in this paper we show how the theory of variational inequalities can be applied to the formulation qualitative analysis and computation of a new competitive spatial market model in the presence of goal targets the model allows the decision maker to impose supply goals at production locations demand goals at consumption locations and transportation goals between supply and demand locations along with associated penalties for failure to comply this work may be viewed as a contribution to the growing literature on the development of mathematical methodologies for policy modeling

introduction to the stability of rational expectations equilibrium abstract this paper surveys the literature which examines the stability of the expectations that agents are assumed to have in a rational expectations equilibrium ree this issue is more complex than the usual statistical estimation problem because the relationship between observable variables and payoff relevant variables is endogenous one approach taken in the literature yields convergence to a ree but requires agents to have extensive knowledge about the structure and dynamics of the model that prevails while they learn a second approach does not assume that agents have correctly specified likelihood functions and finds that ree may not be stable

learning ricardian equivalence abstract this paper tests whether subjects learn to comply with the ricardian equivalence proposition in a life cycle consumption laboratory experiment our results suggest that ricardian equivalence does not hold on average tax changes have a significant and strong impact on consumption choice using individual consumption time series the behaviour of 56 of our subjects can be classified as inconsistent with the ricardian equivalence proposition classifying subjects according to rules of thumb that best describe their behaviour we find that subjects switch less to rules that theoretically violate ricardian equivalence in later rounds compared to earlier rounds this implies that some subjects learn to comply with ricardian equivalence by changing their consumption strategy however the aggregate effect of taxation on consumption persists even after eight rounds of repetition

on the stability of an adjustment process for spatial price equilibrium modeled as a projected dynamical system abstract this paper presents a stability study for the continuous time adjustment process proposed for the perfectly competitive spatial price equilibrium problem modeled as a projected dynamical system by nagurney takayama and zhang 1995 two distinct approaches are adopted here for establishing the stability of the spatial price equilibrium under such an adjustment process one approach utilizes the monotonicity condition on the supply prices demand prices and transaction costs to develop various stability properties the other utilizes the regularity concept adapted from zhang and nagurney 1995 which enables us to explore the stability of the adjustment process a nonstandard dynamical system via its minimal face flow a standard dynamical system

economic models of nato abstract the seminal work of olson and zeckhauser 1966 on the economic theory of alliances in particular nato provides the theoretical background for this paper after restating their results on alliance allocation behavior in a formal framework we show that these results may fail in a context with decentralized production of the public defense commodity finally we introduce a simple mechanism which allows the implementation of an efficient allocation characterized by proportional burden sharing and cost monotonicity these results can also be applied to other public goods problems

spatial price equilibrium with information asymmetry in quality and minimum quality standards abstract a spatial price equilibrium model with information asymmetry in quality is developed in both static and dynamic versions producers at the supply markets are aware of the quality of their products whereas consumers located at the demand markets are aware only of the average quality of the products that are shipped to their demand markets minimum quality standards are also captured in order to assess the impacts of such policy interventions we establish qualitative results in the form of existence uniqueness and stability analysis an algorithm is proposed along with a convergence proof it is then utilized to compute solutions to a spectrum of spatial price equilibrium numerical examples in order to explore the impacts of information asymmetry under different scenarios the numerical examples which are of quite general functional forms reveal that as the number of supply markets increases the anonymizing effect leads to a decrease in the average quality on the other hand as the number of demand markets increases the pressure to improve quality increases and the average quality increases finally we demonstrate that after the imposition of minimum quality standards the average quality at the demand markets increases and the prices also increase

learning to bid the design of auctions under uncertainty and adaptation we examine auction design in a context where symmetrically informed adaptive agents with common valuations learn to bid for a good despite the absence of private valuations asymmetric information or risk aversion bidder strategies do not converge to the bertrand nash equilibrium strategies even in the long run deviations from equilibrium strategies depend on uncertainty regarding the value of the good auction structure the agents learning model and the number of bidders although individual agents learn nash bidding strategies in isolation the learning of each agent by flattening the best reply correspondence of other agents blocks common learning these negative externalities are more severe in second price auctions auctions with many bidders and auctions where the good has an uncertain value ex post

complementarity free riding and the military expenditures of nato allies abstract this paper examines the major influences of an ally s demand for military expenditures demand equations are estimated for a sample of nato nations using the iterative seemingly unrelated regressions technique evidence is presented indicating that structural changes occured in these equations in the early 1970s this instability is the predicted effect of the doctrine of flexible response adopted by nato during this time period the statistical tests show that the medium sized nuclear powers military expenditures responded identically to income and defense spillins the same held true for the lowland allies

a network equilibrium framework for internet advertising models qualitative analysis and algorithms in this paper we develop a network equilibrium framework for the modeling and analysis of competitive firms engaged in internet advertising among multiple websites the model allows for the determination of both the equilibrium online advertising budget as well as the advertising expenditures on the different websites we then specialize the model to the case of fixed online budgets for the firms the governing equilibrium conditions of both models are shown to satisfy finite dimensional variational inequalities we present qualitative properties of the solution patterns as well as computational procedures that exploit the underlying abstract network structure of these problems the models and algorithms are illustrated with numerical examples this paper adds to the growing literature of the application of network based techniques derived from operations research to the advertising marketing arena

an illustration of the essential difference between individual and social learning and its consequences for computational analyses abstract drawing a conclusion from recent insights in evolutionary game theory we show that a so called spite effect implies that there is an essential difference between individual and social learning we illustrate its consequences for the choice of computational tools in economics and social settings in general by analyzing two variants of a genetic algorithm

poverty food intake and malnutrition implications for food security in developing countries the relation between household income food intake and nutritional status in less developed countries is examined and a framework that explicitly relates household behavior patterns with public policy options designed to improve the nutritional status of the rural and urban poor is presented for rural areas nutritional and health status depends largely upon the levels of private inputs provided by households in turn level depends upon income consequently increasing income may also lead to improvements in nutrition and health status regrettably post world war ii development strategy in most developing countries has undervalued the potential contribution of agricultural development to economic development domestic economic policies practiced thus far have most probably had serious negative effects upon the nutrition and heal status of the poorest segments of developing nations economic development policy reform is therefore called for as a measure to alleviate rural poverty in developing countries

local convergence properties of a cobweb model with rationally heterogeneous expectations abstract this paper gives local stability conditions for convergence of the price dynamics in a cobweb model with rationally heterogeneous expectations generalizing the example of brock and hommes 1997 when agents choose between rational naive and adaptive beliefs the steady state may be locally asymptotically stable if the adaptive predictor places enough weight on past prices and is costless if adaptive expectations are sufficiently more costly than naive expectations the steady state will be an unstable saddle point our results imply that adding a choice can stabilize a system which is unstable under the brock and hommes model these results illustrate how the critical parameter that governs stability is dependent on the array of available predictors

approaches to economic equilibrium abstract we study mechanisms that help to explain why and how equilibrium may eventually be attained in many economic settings examples include competitive markets and many noncooperative games the main object is an adaptive process reflecting repeated adjustment of individual strategies which under monotonicity conditions leads to equilibrium environmental uncertainty is accommodated but agents need neither know the probability law nor invoke any statistical learning theory nor compute mean values in fact everyone can act perhaps without precedent maybe among strangers within unidentified frames nonetheless we show under reasonable conditions that individual optimality and system equilibrium obtains in the long run

alternative collective goods models of military alliances theory and empirics i introduction in a seminal article mancur olson and richard zeckhauser 1966 characterized the north atlantic treaty organization nato in the mid 1960s as a group of allies who shared a pure public good in the form of deterrence to qualify as a pure public good a good s benefits must be nonexcludable i e available to all group members once provided and nonrival in consumption i e consumption opportunities associated with a unit of the good do not decline with the number of users pure public goods are characterized by free riding behavior owing to non excludability which permits individuals to partake in the benefits of the good without expending their own scarce resources olson and zeckhauser also demonstrated that a pure public good such as deterrence is associated with an exploitation hypothesis whereby the large agents allies shoulder the payment burdens of the small agents allies using data from 1964 olson and zeckhauser 1966 274 77 established that defense burdens are positively correlated with the economic size of the allies as measured by gross national product gnp over the next twenty five years a large literature has generalized and extended the olson and zeckhauser collective goods theory of alliances van ypersele de strihou 1967 recognized that defense expenditures could generate country specific private benefits e g disaster relief protection of colonies management of domestic unrest along with purely public deterrence with the presence of ally specific benefits the strength of the exploitation hypothesis is attenuated since a small ally might willingly shoulder a relatively large burden provided that this ally views its defense expenditures as possessing a large share of nation specific benefits in a series of articles murdoch sandler and others 1 formulated a joint product model in which the military activity of an ally yields pure public impure public and or private jointly produced outputs or benefits if the benefits derived from the allies military expenditures were from a single purely public good then the joint product model would obviously degenerate to the model of olson and zeckhauser 1966 murdoch and sandler 1984 sandler and forbes 1980 and sandler and murdoch 1990 have shown that the joint product model outperforms the pure public good deterrence model for nato during various time periods in recent years a number of important contributions to the collective good analysis of alliances have appeared these include the inclusion of foreign trade considerations wong 1991 marginal cost differentials among allies mcguire 1990 weber and wiesmeth 1991 leader follower behavior bruce 1990 and median voter considerations dudley and montmarquette 1981 murdoch sandler and hansen 1991 and okamura 1991 mcguire and groth 1985 engineered an econometric procedure for distinguishing between allocative processes e g non cooperative and cooperative within an alliance while subsequent work by sandler and murdoch 1990 operationalized this econometric procedure until now collective good models of alliances have computed alliancewide defense levels by simply summing the allies expenditures however the appropriate manner for aggregating defense efforts among allies may depend on geographical strategic and technological determinants for example the defense efforts of the weakest ally or link along a front may determine the strength of the allies defenses since the enemy s ability to penetrate behind the front hinges on the weakest fortification hirshleifer 1983 in consequence the minimal defense level of the allies and not the sum determines alliance capabilities the purpose of this paper is fivefold first we intend to look at different methods of aggregating allies military expenditures to determine alliancewide defense levels three procedures summation weakest link and best shot are examined

money as a medium of exchange in an economy with artificially intelligent agents abstract we study the exchange economies of kiyotaki and wright 1989 in which agents must use a commodity or fiat money as a medium of exchange if trade is to occur our agents are artificially intelligent and are modeled as using classifier systems to make decisions in the assignment of credit within the classifier systems we introduce some innovations designed to study sequential decision problems in a multi agent environment for most economies that we have simulated trading and consumption patterns converge to a stationary nash equilibrium even if agents start with random rules in economies with multiple equilibria the only equilibrium that emerges in our simulations is the one in which goods with low storage costs play the role of medium of exchange i e the fundamental equilibrium of kiyotaki and wright

sensitivity analysis for the general spatial economic equilibrium problem we consider the general spatial economic equilibrium problem where the supplies and demands at each market for each commodity may depend on the price on this as well as other prices of other commodities at other markets and the transportation cost on each link for each commodity may depend on the flow on this as well as other flows of other commodities on other links in the network for this model we perform stability and sensitivity analysis assuming that the supply demand and transportation cost functions are monotone we first show that the multicommodity equilibrium price pattern depends continuously upon the market supply and demand functions and the multicommodity equilibrium shipment pattern depends continuously upon the transportation cost functions we then focus on the delicate question of predicting the direction of the change in the price and shipment pattern and the incurred supplies demands and transportation costs resulting from changes in the supply demand and transportation cost fu

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

food preference poverty and the nutrition gap in recent decades widespread poverty has been observed in the developing economies studies probing the relationship of development to income distribution or poverty suggest either no development effect on the extent of poverty or a widening of inequality of incomes during the initial stages of development 2 a recent study by dandekar and rath of poverty in india showed the prevalence of poverty in both rural and urban areas after nearly three five year plans although these plans enabled india to achieve a sustained high rate of growth 3 other studies just preceding and following confirmed and extended the major conclusion of dandekar and rath s study 4 while income distribution studies relate to the extent of relative poverty studies similar to dandekar and rath s relate to absolute poverty in the latter the measurement of poverty is related to calorie intake levels in at least one study it is related to a collection of basic goods recent studies at the international level give evidence of poverty in the past decade and project a further spread in the next they too have used the calorie based poverty line 6 in this paper i maintain that calories or other nutrients taken singly or together measure only one attribute of food another is its taste the demand for food is a joint demand for these attributes and others like bulk which gives a sense of fullness i maintain that to concentrate on nutrition or calories alone leads to inaccuracy in measuring the extent of poverty we must ask therefore what role food preferences play in food consumption and nutrition intake my attempt is to understand food habits especially at low income levels although measurements are given regarding food preferences

convergence of least squares learning in environments with hidden state variables and private information we study the convergence of recursive least squares learning schemes in economic environments in which there is private information the presence of private information leads to the presence of hidden state variables from the viewpoint of particular agents by applying theorems of ljung we extend some of our earlier results to characterize conditions under which a system governed by leastsquares learning will eventually converge to a rational expectations equilibrium we apply insights from the learning results to formulate and compute the equilibrium of a version of townsend s model

the demand for military expenditures an international comparison earlier studies have explained inter country variations in the share of gnp devoted to military expenditures by international spillovers and by differences in the threat of attack related to relative incomes in this paper we use the theory of public choice to explain these differences we attempt to measure the importance of both international spillovers and relative incomes along with two other factors the tax price elasticity of demand and economies of scale in the consumption of security we find that international spillovers are significant and positive that the income elasticity of demand is greater than unity that the tax price elasticity of demand explains part of observed inter country differences and that there are considerable economies of scale in the consumption of military spending finally between 1960 and 1975 there was apparently a substantial increase in the value which each country derived from a dollar of military spending by its allies this phenomenon which seems related to the increased importance of deterrent weapons has tended to induce individual alliance members to reduce the share of their national income devoted to defense

will developing country nutrition improve with income a case study for rural south india aggregate estimates of food expenditure are consistent with such a possibility implying income expenditure elasticities close to one however the high degree of aggregation at which such estimates are made means that the considerable increase in price per nutrient as income increases is ignored and the nutrient elasticities are therefore overstated estimates for a rural south indian sample indicate that this bias is considerable and that the true nutrient elasticities with respect to income may be close to zero

tariffs and quotas in world trade a unified variational inequality framework abstract in this paper we develop a unified variational inequality framework in the context of spatial price network equilibrium problems that captures world trade policies in the form of tariff rate quotas which are two tiered tariffs and that have been applied in practice to numerous commodities the spatial price network equilibrium model allows for multiple supply markets and multiple demand markets in different countries as well as multiple transportation routes the model is qualitatively analyzed and also related to models with trade policies such as ad valorem tariffs and strict quotas a case study on the dairy industry focusing on the united states and france is presented to illustrate the modeling and computational framework with impacts of stricter quotas higher over quota tariffs as well as additional transportation routes assessed the numerical examples reveal that although domestic producers can gain under tariff rate quotas consumers may experience higher prices given the relevance of tariffs to global trade in the world today and discussions concerning the impacts the framework constructed in this paper is especially timely

adaptive behavior and economic theory the relationship between psychological and economic views of behavior once a subject of heavy dispute is now understood in a very similar way by practitioners of both these disciplines and of our sister social sciences in general terms we view or model an individual as a collection of decision rules rules that dictate the action to be taken in given situations and a set of preferences used to evaluate the outcomes arising from particular situation action combinations these decision rules are continuously under review and revision new decision rules are tried and tested against experience and rules that produce desirable outcomes supplant those that do not i use the term adaptive to refer to this trial anderror process through which our modes of behavior are determined if one is interested in modeling particular decisions in any very explicit way it is obviously necessary to think about rather narrow aspects of an individual s entire set of decision rules his or her personality experimental psychology has traditionally focused on the adaptive process by which decision rules are replaced by others in this tradition the influence of the subject s or as an economist says the agent s preferences this essay uses a series of examples to illustrate the use of rationality and adaptation in economic theory it is argued that these hypotheses are complementary and that stability theories based on adaptive behavior may help to narrow the class of empirically interesting equilibria in certain economic models an experiment is proposed to test this idea

progression under the benefit approach to the theory of taxation abstract the implications for progression of the benefit approach to the theory of taxation are studied in this paper it is concluded that the case for progression rests on the degree of substitutability between public and private goods

egalitarian equivalent cost sharing of a public good in an economy with one public and one private good egalitarian equivalent cost sharing consists of finding the highest public good level x such that consuming x for free yields a feasible utility distribution the corresponding feasible allocation typically unique called egalitarian equivalent is in the core of the economy conversely any cost sharing method satisfying pareto optimality cost monotonicity nobody suffers a utility loss if the production technology improves upon ceteris paribus and individual rationality no single agent coalition objects or no private transfers no agent receives a positive amount of private good must select an egalitarian equivalent allocation in every economy copyright 1987 by the econometric society

agricultural incentives in developing countries measuring the effect of sectoral and economywide policies the impact of sector specific direct and economywide indirect policies on agricultural incentives for 18 developing countries for the period 1975 84 are estimated the direct effect is measured by the proportional difference between the producer price and the border price adjusting for distribution storage transport and other marketing costs the indirect effect has two components 1 the impact of the unsustainable portion of the current account deficit and of industrial protection policies on the real exchange rate and thus on the price of agricultural commodities relative to nonagricultural nontradables and 2 the impact of industrial protection policies on the relative price of agricultural commodities to that of nonagricultural tradable goods the authors found that a in almost all cases the direct effect is equivalent to a tax on exportable goods and to a subsidy for importables b the indirect effect also taxes agriculture and dominates the direct effect and c the direct policies for both importables and exportables stabilize domestic producer prices

learning dynamics genetic algorithms and corporate takeovers abstract this paper simulates via a genetic learning algorithm free riding and coordination failure when shareholders are confronted with an unconditional tender offer bid between the pre takeover and post takeover value of their firm the outcomes produced by the simulations offer strong support for the hypothesis that coordination to tendering strategies permitting offer success is impaired by increasing the number of shareholders and the divisibility of shareholdings further the outcomes of the simulations closely conform to the restrictions imposed by the nash equilibrium hypothesis when the number of shareholders and the disability of shareholdings are both small the aggregate outcomes of the simulations converge to the aggregate outcomes produced by efficient nash equilibria otherwise the outcomes of the simulation more closely resemble the outcomes of inefficient nash equilibria

social learning and monetary policy rules we analyse the effects of social learning in a monetary policy context social learning might be viewed as more descriptive of actual learning behaviour in complex market economies in our model taylor principle governs uniqueness and expectational stability of rational expectations equilibrium ree under homogeneous recursive algorithms we find that the taylor principle is not necessary for convergence to ree minimum state variable msv equilibrium under social learning sunspot equilibria exist in the indeterminate region our agents cannot co ordinate on a sunspot equilibrium in general form specification however they can co ordinate on common factor specification we contribute to the use of genetic algorithm learning in stochastic environments

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

structuring international institutions for the efficient provisioning of global security this paper analyzes the issue of security provision by an alliance against the threat of a rogue nation proactive security effort by an alliance member is assumed to be non rival and non excludable so the results of the effort jointly accrue to every other member this effort has both positive and negative effects as security measures mitigate the threat but also involve loss of commercial benefits collateral damages and infringement on human rights in this paper i suggest an institutional structure for the alliance which would lead to the achievement of the efficient level of world security through multilateral participation

on convergence of the pies algorithm for computing equilibria equilibria in market models with continuous market supply functions can be obtained by computing fixed points with an activity analysis representation of production fixed point algorithms would converge slowly further since the market model here is of a partial equilibrium nature the market demand function may not exhibit the integratability condition precluding the formulation of the market equilibrium problem as an economic surplus maximization problem we examine an iterative algorithm the pies method for locating equilibria in markets whose production is described by optimization over a finite set of activities and whose econometric demand function does not possess the integrability property convergence properties of the algorithm along with existence and uniqueness of market equilibrium are summarized

carl s nonlinear cobweb abstract this essay surveys some of my work on expectations learning and bounded rationality within the classical cobweb model following early inspiring ideas from carl chiarella in particular i focus on the role of nonlinear dynamics learning and heterogeneity within the cobweb framework and how price fluctuations in the cobweb theory fit with observations of individual and aggregate behaviour from laboratory experiments with human subjects