impact of off farm income on food security and nutrition in nigeria abstract while the poverty implications of off farm income have been analyzed in different developing countries much less is known about the impact of off farm income on household food security and nutrition here this research gap is addressed by using farm survey data from nigeria econometric analyses are employed to examine the mechanisms through which off farm income affects household calorie and micronutrient supply dietary quality and child anthropometry we find that off farm income has a positive net effect on food security and nutrition the prevalence of child stunting underweight and wasting is lower in households with off farm income than in households without using a structural model we also show that off farm income contributes to higher food production and farm income by easing capital constraints thus improving household welfare in multiple ways

three minimal market institutions with human and algorithmic agents theory and experimental evidence we define and examine the performance of three minimal strategic market games sell all buy sell and double auction in laboratory relative to the predictions of theory unlike open or partial equilibrium settings of most other experiments these closed exchange economies have limited amounts of cash to facilitate transactions and include feedback general equilibrium theory since it abstracts away from market mechanisms and has no role for money or credit makes no predictions about how the paths of convergence to the competitive equilibrium may differ across alternative mechanisms

multiple round timber auction design and simulation this paper presents a multiple round timber auction simulation developed in order to study various configurations of auction design in this study simultaneous sequential timber auctions are modelled and analysed using agent based simulation technology as there are many individual items in the auction to be sold the auction designer defines several rounds that are sequential at pre defined intervals at each round the auction designer announces several simultaneous auctions since bidders are offered different items at each round a mathematical linear programing model for selecting the best set of items to bid for is presented different bidding patterns are simulated and compared in various setup configurations the most advanced of these strategies are adaptive and use agent learning capability the comparisons include the success rate of winning the auction and the winning price per m3 this study suggests an efficient bidding pattern for bidders to bid in order to achieve to their goal and increase their profit similarly in order to increase profit the auctioneer i e the government needs to control several auction parameters including the number of auctions per year the lot size the auction periodicity and the number of bidders this study also suggests parameters configurations that to maximise revenue for the auctioneer

a cointegration analysis of petroleum futures prices abstract this paper presents evidence concerning the number of common stochastic trends in a system of three petroleum futures prices crude oil heating oil and unleaded gasoline using daily data from 3 december 1984 to 30 april 1993 johansen s maximum likelihood approach for estimating long run relations in multivariate vector autoregressive models is used the results indicate the presence of only one common trend

the walrasian tatonnement mechanism and information this article reports the results of experiments analyzing the walrasian t tonnement mechanism the t tonnement mechanism has the following characteristics there is only one price at any time there is an information mechanism notifying all traders of the price there is a mechanism for determining quantities offered for sale and purchase at the price and transactions at nonequilibrating prices are forbidden in addition the walrasian pricing rule is utilized by the auctioneer the change in price has the same sign as excess demand the treatment variable used in the experimental design is the degree of segregation of buyers and sellers complete segregation means sellers cannot discover the number of buyers and buyers cannot discover the number of sellers at an announced price the results show that the auction mechanism is stable it exhibits strong convergence properties and efficiency levels averaging better than 97 segregation of the buyers from the sellers leads to a significant difference in underrevelation of demand relative to supply

equilibrium selection in an experimental macroeconomy author affiliation vivian lei department of economics university of wisconsin milwaukee milwaukee wi 53201 usa vlei uwm edu corresponding authorcharles n noussair department of economics faculty of economics and business tilburg university p o box 90153 5000 le tilburg the netherlands c n noussair uvt nl acknowledgment we are grateful to the college of letters and science and center for research on international economics at the university of wisconsin milwaukee for financial support we thank colin camerer katarina kellar lutz hendricks nazrul islam tomomi tanaka filip vesely and two anonymous referees for helpful comments 1 introductionone of the most influential literatures in economics is the theory of growth for surveys see azariadis 1993 barro and sala i martin 1995 romer 1996 sala i martin 2002 the basis of much of the literature is the ramsey 1928 cass 1965 koopmans 1965 growth model in this model the economy is assumed to behave like a benevolent social planner who chooses capital stock and consumption levels over an infinite time horizon with the goal of maximizing the discounted utility of the consumption stream the principal result of the model is that consumption and capital stock converge to unique optimal steady state levels that are independent of the initial endowment and the utility function of the social planner an implication of the model therefore is that different countries would converge toward a common income level even if their initial endowment of capital differed provided that they have access to the same production technology relatively poor countries would exhibit higher growth rates than richer ones these two predictions are testable with field data however field studies have generally failed to support the hypothesis of convergence toward a common income level see durlauf and quah 1999 temple 1999 and islam 2003 for surveys rather the data are more consistent with the alternative hypothesis of club convergence baumol 1986 which postulates that a small number of steady states exist and that each country has a tendency to converge toward one of them 1 such a framework can explain the observed pattern over time of an increase in income differences between the organisation for economic cooperation and development countries and the developing world as well as a decrease in the differences within each of the two groups the empirical support for club convergence has encouraged the development of theoretical models with multiple equilibria while some countries may reach optimal equilibria unfortunate countries might find themselves in low income equilibria which are often labeled as poverty traps these countries are unable to reach a better equilibrium without coordination originally due to rosenstein rodan 1943 the insight that the existence of multiple equilibria might provide an explanation of international income differences has led to a literature that considers a variety of growth models with multiple equilibria for example azariadis and drazen 1990 construct an overlapping generations model with two stable pareto rankable equilibria in the inferior equilibrium no agent trades with members of other generations murphy shleifer and vishny 1989 build a model with synergies between industries each industry is profitable only if other industries are operating and there are equilibria where all of the industries operate and other pareto dominated equilibria where none operate galor and zeira 1993 and banerjee et al 2001 show that inequality and differential access to credit can keep an economy in a pareto dominated equilibrium recognizing whether or not an economy has multiple equilibria is important because policy prescriptions differ depending on whether an economy is in an inferior equilibrium or whether it is in an equilibrium that is unique

price discovery and learning during the preopening period in the paris bourse before the opening of the paris bourse traders place orders and indicative prices are set this offers a laboratory to study empirically the t tonnement process through which markets discover equilibrium prices since preopening orders can be revised or canceled before the opening indicative prices could be noise we test this against the hypothesis that preopening prices reflect learning early in the preopening the noise hypothesis is not rejected as the opening gets closer the informational content and efficiency of prices increase and the learning hypothesis is not rejected we also propose a gmm based estimate of the speed of learning

limited rationality and strategic interaction the impact of the strategic environment on nominal inertia much evidence suggests that people are heterogeneous with regard to their abilities to make rational forward looking decisions this raises the question as to when the rational types are decisive for aggregate outcomes and when the boundedly rational types shape aggregate results we examine this question in the context of a long standing and important economic problem the adjustment of nominal prices after an anticipated monetary shock our experiments suggest that two types of bounded rationality money illusion and anchoring are important behavioral forces behind nominal inertia however depending on the strategic environment bounded rationality has vastly different effects on aggregate price adjustment if agents actions are strategic substitutes adjustment to the new equilibrium is extremely quick whereas under strategic complementarity adjustment is both very slow and associated with relatively large real effects this adjustment difference is driven by price expectations which are very flexible and forward looking under substitutability but adaptive and sticky under complementarity moreover subjects expectations are also considerably more rational under substitutability

an experimental investigation of the patterns of international trade this study is the first attempt to create and study a laboratory economy with some of the prominent features of an international economic system the concept of multiple countries in which each country has its own technology preferences and resource endowments is introduced and operationalized the questions posed in the study are related to the law of comparative advantage factor price equalization terms of trade efficiency in production and exchange as guided by multiple and interacting markets and the effects of tariffs on international transactions the study builds on previous work in the experimental study of general equilibrium phenomena

testing for common features in north american energy markets abstract using recent advances in the field of applied econometrics we explore the strength of shared trends and shared cycles between north american natural gas and crude oil markets in doing so we use daily data from january 1991 to april 2001 on spot u s henry hub natural gas and wti crude oil prices the results show that there has been decoupling of the prices of these two sources of energy as a result of oil and gas deregulation in the united states we also investigate the interconnectedness of north american natural gas markets and find that north american natural gas prices are largely defined by the u s henry hub price trends

co learning patterns as emergent market phenomena an electricity market illustration abstract the definition of emergence remains problematic particularly for systems with purposeful human interactions this study explores the practical import of this concept within a specific market context namely a double auction market for wholesale electric power that operates over a transmission grid with spatially located buyers and sellers each profit seeking seller is a learning agent that attempts to adjust its daily supply offers to its best advantage the sellers are co learners in the sense that their supply offer adjustments are in response to past market outcomes that reflect the past supply offer choices of all sellers attention is focused on the emergence of co learning patterns that is global market patterns that arise and persist over time as a result of seller co learning examples of co learning patterns include correlated seller supply offer behaviors and correlated seller net earnings outcomes heat maps are used to display and interpret co learning pattern findings one key finding is that co learning strongly matters in this auction market environment sellers that behave as gode sunder budget constrained zero intelligence agents randomly selecting their supply offers subject only to a break even constraint tend to realize substantially lower net earnings than sellers that tacitly co learn to correlate their supply offers for market power advantages

fairness price stickiness and history dependence in decentralized trade this chapter investigates the implications that social preferences have for the stationary strategic equilibrium of such a decentralized market agents are supposed to be averse to unfairly unfavorable as well as unfairly favorable deals in the spirit of fehr and schmidt 1999 but we stay rather close to standard individualistic preferences the negative weights on advantageous and disadvantageous deviations from what is considered as the fair benchmark are such that utility remains strictly increasing in own surplus share and in contrast to the original fehr schmidt model the fair split need not automatically be a 50 50 division any price between sellers cost and buyers willingness to pay may be the one which for whatever reasons is agents reference point in a given market this makes it possible to consider a more flexible notion of fairness than is usually done it is in line with cognitive dissonance theory from psychology and the noteworthy experiments of binmore et al 1991 1993 where subjects who were triggered to play different bargaining equilibria ended up considering very different surplus distributions as fair

an interdisciplinary model for macroeconomics macroeconomic modelling has been under intense scrutiny since the great financial crisis when serious shortcomings were exposed in the methodology used to understand the economy as a whole criticism has been levelled at the assumptions employed in the dominant models particularly that economic agents are homogeneous and optimizing and that the economy is equilibrating this paper seeks to explore an interdisciplinary approach to macroeconomic modelling with techniques drawn from other natural and social sciences specifically it discusses agent based modelling which is used across a wide range of disciplines as an example of such a technique agent based models are complementary to existing approaches and are suited to answering macroeconomic questions where complexity heterogeneity networks and heuristics play an important role

walras s models of the barter of stocks of commodities abstract the models are described in regard to their features that determine and express the pricing and exchange processes namely their physical characteristics participants institutions procedures rules and behavioral patterns it is shown that walras s arbitrage model is defective and walrasian arbitrage is not an equilibriating mechanism in the models that the other barter models are complete functioning systems that the numeraire does not simplify pricing in the models that the characteristics of the pricing process in the models do not involve a central or particular market authority and that they do not use or logically depend on the assumption of large numbers of traders

impact of off farm income on food expenditures in rural bangladesh an unconditional quantile regression approach this study examines the effects of off farm income on food expenditures of rural bangladeshi households our analysis yields unbiased estimates of the unconditional impact of off farm income on food expenditures and reveals the heterogeneous effects that occur across the distribution of total food consumption expenditures the findings suggest that the impacts of off farm income are uniformly positive across the unconditional quantile regression and significantly increase food consumption expenditures for all quantiles except for the 25th quantile in addition we found that schooling experience and location of the household increase the food expenditures of rural households most importantly this article argues that female headed rural households in which the female works off the farm tend to have significantly lower food expenditures

learning to deal with repeated shocks under strategic complementarity an experiment experimental evidence shows that the rational expectations hypothesis fails to characterize the path to equilibrium after an exogenous shock when actions are strategic complements under identical shocks however repetition allows adaptive learning so that inertia in adjustment should fade away with experience if this finding proves to be robust inertia in adjustment may be irrelevant among experienced agents the conjecture in the literature is that inertia would still persist perhaps indefinitely in the presence of real world complications such as nonidentical shocks herein we empirically test the conjecture that the inertia in adjustment is more persistent if the shocks are nonidentical for both identical and nonidentical shocks we find persistent inertia and similar patterns of adjustment that can be explained by backward looking expectation rules a reformulation of naive expectations with similarity based learning approach is found to have a higher predictive power than rational and trend following rules

do institutions promote rationality an experimental study of the three door anomaly the three door problem is an example of a systematic violation of a key rationality postulate that has attracted much attention in this seemingly simple individual decision task most people initially fail to apply correctly bayes law and to make the payoff maximizing choice previous experimental studies have shown that individual learning reduces the incidence of irrational choices somewhat but is far from eliminating it we experimentally study the roles of communication and competition as institutions to mitigate the choice anomaly we show that the three door anomaly can be entirely eliminated by these institutions

ex post impacts of improved maize varieties on poverty in rural ethiopia public agricultural research has been conducted in africa for decades while many studies have examined its aggregate impacts few have investigated how it affects the poor this paper helps fill this gap by applying a new procedure to explore the ex post impacts of improved maize varieties on poverty in rural ethiopia plot level yield and cost changes due to adoption are first estimated using instrumental variable and marginal treatment effect techniques where possible heterogeneity is carefully accounted for a backward derivation procedure is then developed to link treatment effect estimates with an economic surplus model to identify the counterfactual household income that would have existed without improved maize varieties poverty impacts are finally estimated by exploiting the differences between observed and counterfactual income distributions improved maize varieties have led to a 0 8 1 3 percentage drop of poverty headcount ratio and relative reductions of poverty depth and severity however poor producers benefit the least from adoption due to the smallness of their land holdings

papers in experimental economics competitive market institutions double auctions vs sealed bid offer auctions consider a market with the following characteristics 1 privacy that is each agent knows only his own valuation or cost conditions 2 exchange follows the rules of the oral double auction that is buyers freely announce bids or accept offers and sellers freely announce offers or accept bids 3 aggregate market supply and demand per trading period is stationary for at least two to three periods and 4 there are at least four buyers and as many sellers the literature reporting the results of a large number of experimental markets with these characteristics documents what appears to be a remarkably rapid convergence to a competitive equilibrium ce however any claim of double auction da convergence to the ce can only have meaning in one of three senses i the ce is attained immediately ii after t periods of trading some measure of the market s state such as mean price is nearer relative to experimental sampling variability to a ce than to some distinct alternative equilibrium such as a monopoly or nash equilibrium iii after t periods of trading this measure is nearer to a ce in da experimental markets than in markets organized under a different institution of contract for example a sealed bid auction since everything from electrons and the stars to rats and people yield state measures subject to error or random variation the deterministic criterion i can have no serious scientific standing by such criteria any hypothesis can be rejected and there could be no science of physics biology or economics 2 with the exception of certain very simple markets such as single object auctions or certain idealized markets such as the cournot quantity adjuster model economics has only two concepts of equilibrium monopoly and competitive the only formal model of da trading that has been proposed see david easley and john ledyard p 6 predicts stochastic convergence in finite time with probability one to a ce hence the only test alternative to the ce research hypothesis in da markets is a monopoly or monopsony equilibrium experimentalists have not reported statistical tests of the ce professor department of economics university of arizona assistant professor department of economics indiana university instructor department of economics university of arizona and sandia national laboratories albuquerque nm respectively we are indebted to the national science foundation for research support and to art denzau and mort kamien for helpful comments there is an early and recently growing body of experimental evidence for convergence to a competitive equilibrium under double auction rules the earliest evidence contained in experiments initiated in january 1956 is reported in smith 1962 1964 1965 1976 however these early experiments used between twenty and fifty or so participant buyers and sellers because in keeping with prevailing professional beliefs it was thought that a ce was unlikely to be approached unless numbers were quite large using large numbers was not unreasonable since it is a good beginning procedure to give a theory whatever is believed to be its best shot more recent evidence using six buyers six sellers and two traders in speculative da markets with cyclical demand is reported by r m miller charles plott and smith and williams 1979 for evidence from a comparison of oral and computerized da experiments with four buyers and four sellers see williams 1980 for further evidence in the context of the study of price controls see m isaac and plott 1981b and smith and williams 1981b in the context of a conspiracy study see isaac and plott 1981a in the context of comparisons between da and posted offer pricing see jon ketcham smith and williams in the context of a study of four variations on da rules see smith and williams 1980 all of these more recent papers report double auction experiments using no more than four buyers and four sellers 2as frederick mosteller once noted if you wanted to reject the inverse square law of attraction try tossing a sheet of paper out the window

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

oil and the macroeconomy since world war ii all but one of the u s recessions since world war ii have been preceded typically with a lag of around three fourths of a year by a dramatic increase in the price of crude petroleum this does not mean that oil shocks caused these recessions evidence is presented however that even over the period 1948 72 this correlation is statistically significant and nonspurious supporting the proposition that oil shocks were a contributing factor in at least some of the u s recessions prior to 1972 by extension energy price increases may account for much of post opec macroeconomic performance

markets as information gathering tools the academic literature wall street commentary and even daily news reporting reflect a belief that markets can anticipate events the current movements in the stock market are interpreted as reflecting the likelihood that the federal reserve system will change interest rates futures markets are interpreted as reflecting the best estimates of things to come movements in individual stock prices are thought to anticipate earnings reports or the probability of a merger or buyout if we want to know about future weather in the south we should study the orange juice futures the academic journals are filled with the concept of rational expectations in which current prices are supposed to reflect the sum of all knowledge in the system prices according to this theory are a statistic that indicates the aggregation of information about underlying states of the economy those who are outsiders to the information in the system become insiders by simply observing the economic activity

a rule of one a rule ofone one rational person is enough to make a market one irrational person is enough to break a game let me explain the power of the market as an exchange institution rests in its ability to move resources from lowto highvalued uses the market works if one person is rational enough to look for arbitrage opportunities among the other irrational players he buys low and sells high the market collects and disseminates this information such that others

marshall and walras disequilibrium trades and the dynamics of equilibration in the continuous double auction market prices and quantities converge to the theoretical competitive equilibria in continuous double auction markets the double auction is not a tatonnement mechanism disequilibrium trades take place the absence of any influence of disequilibrium trades which have the capacity to change the theoretical equilibrium appears to be due to a property found in the marshallian model of single market adjustments the marshallian model incorporates a principle of self organizing coordination that mysteriously determines the sequence in which specific pairs of agents trade in an environment in which market identities and agent preferences are not public disequilibrium trades along the marshallian path of trades do not change the theoretical equilibrium the substance of this paper is to demonstrate that the marshallian principle captures a natural tendency of the adjustment in single continuous double auction markets and to suggest how it takes place the marshallian model of quantity adjustment and the walrasian model of market price adjustment can be seen as companion theories that explain the allocation and price processes of a market the marshallian model explains the evolution of the allocation who will meet and trade and the walrasian excess demand explains the evolution of prices when they do

experimental economics accounting and society in memory of john dickhaut abstract this volume consists of papers presented at a conference in memory of john dickhaut the conference sponsored by the economic science institute at chapman university focused on four areas of john s research interests during his career accounting and society methodology in experimental economics neural economics and trust and reciprocity all of the papers make novel interesting contributions to the study of human behavior in economic institutions and should interest readers in a range of fields including accounting anthropology economics finance neurology and psychology

walrasian and marshallian stability abstract it is well known that there is no direct relation between stability of the walrasian t tonnement process and stability of the marshallian quantity adjustment process it is shown that if short run walrasian t tonnement with a given number of firms is distinguished there is under the assumption of no joint production local stability of the short run walrasian adjustment process if and only if there is local stability of the long run marshallian adjustment process with exit and entry of firms according to profit levels

does adaptation to climate change provide food security a micro perspective from ethiopia we examine the driving forces behind farmers decisions to adapt to climate change and the impact of adaptation on farmers food production we investigate whether there are differences in the food production functions of farm households that adapted and those that did not adapt we estimate a simultaneous equations model with endogenous switching to account for the heterogeneity in the decision to adapt or not and for unobservable characteristics of farmers and their farm we compare the expected food production under the actual and counterfactual cases that the farm household adapted or not to climate change we find that the group of farm households that adapted has systematically different characteristics than the group of farm households that did not adapt the relationship between production and average temperature is inverted u shaped for farm households that adapted while it is u shaped for farm households that did not adapt and vice versa in the case of precipitation we find that adaptation increases food production however the impact of adaptation on food production is smaller for the farm households that actually did adapt than for the farm households that did not adapt in the counterfactual case that they adapted

marshallian vs walrasian stability in an experimental market the experiments discussed below are an attempt to examine concepts of stability as found in economic textbooks two concepts of stability which stem from two different concepts of market adjustment seem to have dominated thinking whilst these two concepts are typically called walras stability and marshall stability some controversy exists over the extent to which these two models represent their respective thinking no doubt the current formal statements of the theories reflect an evolution of the ideas through the work of many theorists the terminology is retained for convenience regardless of their origins these two concepts lead to competing hypotheses about the conditions under which market instability will be observed so the subject is a natural one for experimental investigation furthermore since this is the first experimental examination of the stability of equilibria the strategy is to inquire about stability in the context of these two classical models and to avoid the temptation to attempt to extend them or integrate them with more modern theory the old models have not been checked they seem to be an appropriate place to start

market simulation and the provision of public goods a non paternalistic response to anomalies in environmental evaluation most normative economics assumes that individuals have coherent preferences this paper responds to growing evidence of failures of this assumption particularly in the context of stated preference methods widely used in environmental policy analysis it proposes a non paternalistic concept of consumer sovereignty that does not assume preference coherence is satisfied by competitive markets and can be applied to the provision of public goods a key implication is that decisions should reflect valuations revealed at the point of consumption such valuations which can be inferred from hedonic prices may be less susceptible to willingness to accept wta willingness to pay wtp disparities than those elicited by stated preference methods

iteration tâtonnement computation and economic dynamics an attempt is made in this paper to extract a mathematical methodology underpinned by numerical meaning from a study of richard goodwin s classic contributions from 1943 to 1967 and beyond the key conceptual notions used are t tonnement computation approximations the geometry of dynamics simulations and iteration

extreme walrasian dynamics the gale example in the lab we study the classic gale 1963 economy using laboratory markets tatonnement theory predicts prices will diverge from an equitable interior equilibrium towards infinity or zero depending only on initial prices the inequitable equilibria determined by these dynamics give all gains from exchange to one side of the market our results show surprisingly strong support for these predictions in most sessions one side of the market eventually outgains the other by more than twenty times leaving the disadvantaged side to trade for mere pennies we also find preliminary evidence that these dynamics are sticky resisting exogenous interventions designed to reverse their trajectories

price formation in double auction markets abstract this paper reports 14 laboratory experiments that examine existing theories of the price formation process in the continuous double auction the experiments feature random values and costs and therefore a new price formation observation each period we find that efficiency is high and rises with experience in this environment we also find that trades with greater exchange surplus tend to occur earlier in the period that increased trader experience reduces an anomalous intertemporal arbitrage opportunity observed previously and that only when traders are very experienced does exchange surplus accrue disproportionately to the side of the market with a smaller number of traders

markups in double auction markets abstract we study the continuous double auction cda market with simulated traders using three simple markup rules relative to analytic results obtained for markups in the simpler call market cm we find that uniform cda markups have a more complex and non monotonic impact on cda market outcomes such as price volume and efficiency the symmetric nash equilibrium markup in the cda is remarkably close to the most efficient markup in thick markets which may partially explain the mysterious efficiency for cda market

soil and water conservation technology adoption and labour allocation evidence from ethiopia abstract soil and water conservation swc technologies are viewed as part of a solution to increase the resilience of the agriculture sector to climate change research has shown that swc technologies are effective at controlling erosion and increasing yields but are labour intensive however the quantification of their labour impacts remains an important research gap in this paper i estimate the labour impacts of adopting swc technologies in ethiopia using an endogenous switching regression model esrm i find that adopting swc technologies increases plot level adult labour by 35 impacts on child labour depend on the number of adults in the household specifically estimated impacts range from 29 for the full sample to 78 for the sub sample of households with fewer than three adults i also find some evidence of negative self selection in the case of child labour which suggests that adopters have a comparative advantage since they are able to adopt the technology with smaller impacts on child labour as a result of unobservable characteristics the estimated labour impacts also provide a plausible explanation for why farmers may not adopt swc technologies despite their economic profitability ultimately the paper argues that understanding the heterogeneity and magnitude of the labour impacts is an important part of understanding potential trade offs of adopting swc technologies given the estimated labour impacts policies that relax the household s labour constraints could be an effective mechanism to spur the adoption of labour intensive environmentally agricultural practices while minimizing potential negative effects

demand revelation and tâtonnement auctions abstract the t tonnement process is inherently a price taking process an auctioneer calls out a price and traders respond with a quantity signal this t tonnement groping process contrasts with a double auction continuous bid ask process that utilizes price signals do traders in this institution fully reveal quantity or do they underreveal affecting price quantity and efficiency in the experiments reported here traders playing against a fully revealing automaton systematically attempt to manipulate price by underrevealing quantity bid or offered

instability of equilibria in experimental markets upward sloping demands externalities and fad like incentives the objective of the paper is to study markets in which the value of the activity to any one person increases with the level with which the activity is undertaken by others the general interpretation could be fads mimicking behavior or some sort of belief formation process in which the beliefs or expectations of agents about some underlying state of nature are influenced by the buying behavior of other agents the result is to create a market that can be modeled as having an upward sloping market demand curve the questions posed are 1 in the fad like environment does the classical concept of equilibrium as an equating of market demand and market supply accurately predict market behavior ii can both stable and unstable equilibria be observed and iii which of the two classical concepts of stability best describes the conditions under which instability is obeserved under the conditions of a fad like demand side externality in a market organized by the multiple unit double auction muda market equilibration occurs at a point where demand equals supply the disequilibrium behavior follows the dynamics of the marshallian model of dynamics as opposed to the walrasian model these results confirm and extend the major findings of plott and george who studied a similar environment with a downward sloping supply

walras s theories of tatonnement it is shown that leon walras developed two separate theories of tatonnement one is a disequilibrium production model the other is a pledges model in which transactions and production occur only at the equilibrium set of prices these models are explained and the manner in which they appear in the vari ous editions of walras s elements is used to account for the developm ent of conflicting interpretations of his writings on tatonnement it is shown that the disequilibrium production model is more representa tive of walras s work than the pledges model and that the latter is i ncompatible with the theories of particular aspects of economic behav ior on which the elements depends for its verisimilitude and explanat ory power copyright 1987 by university of chicago press

price formation in double auctions abstract we develop a model of information processing and strategy choice for participants in a double auction sellers in this model form beliefs that an offer will be accepted by some buyer similarly buyers form beliefs that a bid will be accepted these beliefs are formed on the basis of observed market data including frequencies of asks bids accepted asks and accepted bids then traders choose an action that maximizes their own expected surplus the trading activity resulting from these beliefs and strategies is sufficient to achieve transaction prices at competitive equilibrium and complete market efficiency after several periods of trading journal of economic literatureclassification numbers d41 d44 d8

soil erosion and smallholders conservation decisions in the highlands of ethiopia abstract soil erosion is one of the most serious environmental problems in ethiopia coupled with growing populations falling per capita food production and worsening poverty loss of productive land due to land degradation undermines rural livelihoods and national food security despite their awareness of the erosion problem peasants investments in land have been limited we use an applied nonseparable model to simulate conservation decisions pervasive market imperfections poverty and high rates of time preference seem to undermine erosion control investments lack of technologies which provide quick returns to subsistence constrained peasants also seem to deter such investments lower private incentives to internalize the intertemporal land degradation externality may require public intervention

allocation of track capacity experimental evidence on the use of priority auctioning in the railway industry allocation of track capacity concerns multiple users facing demand indivisibilities running trains over an inelastic supply of railway tracks the paper suggests a vickrey type mechanism to handle incentive aspects of this technically complex optimisation task here the price for operating a train will correspond to the bids foregone by other operators who are pushed off their preferred routes the paper reports the results of 11 experimental markets using variations of this mechanism where each market includes up to 10 trading periods and subjects bid for routes over a highly stylised railway network the experiments generated solutions that capture 90 100 of potential benefits

comovement or safe haven the effect of corruption on the market risk of sovereign bonds of emerging economies during financial crises in this study i explore the role of corruption in the cross market time varying linkage between sovereign bonds of emerging markets and the us stock market it shows that corruption plays a prominent role in the behaviour of capm beta under different market conditions the sensitivity of sovereign bonds issued by countries perceived as more corrupt to systematic shocks increases during financial crises the prices of bonds issued by less corrupt countries are determined more idiosyncratically under extreme market conditions and realize more hedging benefits against s p 500 risk to explain these findings i integrate results from behavioural finance i propose a comovement model built on barberis et al 2005 where investors load more worldwide news on sovereign bonds issued by more corrupt countries when their sentiment deteriorates

economists models of learning abstract economic theorists have intensively studied learning in games and decisions over the last decade this essay puts some of the work in perspective and offers opinions about what still needs to be learned journal of economic literature classification numbers c73 d83

market theories evolve and so do markets responding to mirowski s target article this paper discusses some intellectual currents of the 1970s to 1990s and offers suggestions on measuring market performance on including automated agents as market participants on evolving new market formats and on dealing with highly differentiated goods acknowledgments i am grateful to associate editor rosser for inviting me to participate in this symposium and to philip mirowski for writing a timely and engaging target article some of the material comes from a recent nsf proposal co written with james c cox the paper mentions many other intellectual debts of course i retain sole responsibility for lapses of style and substance

price expectations and international quota trading an experimental evaluation this paper reports a preliminary experimental test of international quota trading on a market characterized by several dominant traders uncertain quota demand and supply imply true market clearing prices that in general differ from an expected competitive quota price however in the experiment the expected price level emerges as a focal point on which the bulk of quota trade contracts are keyed thus incomplete price discovery occurs

production trade prices exchange rates and equilibration in large experimental economies we study market equilibration in laboratory economies that are larger and more complex than any that have been studied experimentally to date complexity is derived from the fact that the economies are international in economic structure with multiple input output and foreign exchange markets in operation the economies have twenty one markets and due to the fact that they have roughly fifty agents the economies are characterized by several hundred equations in spite of the complexity and interdependence of the economy the results demonstrate the substantial power of the general equilibrium model of perfect competition to predict the direction of movement of market level variables empirical patterns in the convergence process are explored and described

global instability in experimental general equilibrium the scarf example scarf 1960 proposed a market environment and a model of dynamic adjustment in which the standard tatonnement price adjustment process orbits around rather than converges to the competitive equilibrium hirota 1981 characterized the price paths by the configuration of endowments we explore the predictions of scarf s model in a nontatonnement experimental double auction we find that the average transaction prices in each period do follow the path predicted by the scarf and hirota models when the model predicts prices will converge to the competitive equilibrium our data converge when the model predicts prices will orbit our data orbit the equilibrium and in the direction predicted by the model moreover we observe a weak tendency for prices within a period to follow the path predicted by the model

examining the effectiveness of price limits in an artificial stock market abstract this paper proposes an agent based framework to examine the effectiveness of price limits in an artificial stock market the market is composed of many boundedly rational and heterogeneous traders whose learning behavior is represented by a genetic programming algorithm we calibrate the model to replicate several stylized facts observed in real financial markets based on this environment the impacts of price limits are analyzed from the perspectives of volatility price distortion volume and welfare we find that the imposition of price limits possesses both positive and negative effects however compared with the market without price limits appropriate price limits help to reduce volatility and price distortion and increase the liquidity and welfare

price dynamics in general equilibrium experiments general equilibrium ge theory faces several related challenges classical theories of out of equilibrium adjustment are intuitive but implausibly centralized further standard restrictions on individual preferences place little structure on aggregate excess demand functions amongst other issues this fact implies that economies can be unstable under classical dynamics and thus instability appears to be an unavoidable feature of ge theory this paper recounts laboratory studies of ge environments which reveal that classical theories of dynamics do in fact organize market activity surprisingly well these experiments suggest that the walrasian auctioneer for example appears to be a constructive abstraction and that instability should be accommodated within theory rather than circumscribed laboratory applications of ge theory focused on issues beyond stability and dynamics are also briefly surveyed

redistribution and market efficiency an experimental study abstract we study the interaction between competitive markets and income redistribution that reallocates unequal pre tax market incomes away from the rich to the poor majority in one setup participants earn their income by trading in a double auction da with exogenous zero or full redistribution in another setup after trading they vote on redistributive tax policies in a majoritarian election with two competing candidates this results in virtually full redistribution even when participants have the opportunity to influence taxes by transferring money to the candidates we find that the high redistribution reduces trading efficiency but not as much as predicted if market participants trade randomly this is because rather than capitulating to the much lower trading incentives many participants respond to redistribution by asking and bidding more conservatively in the da and in this way help to prevent further efficiency losses

perfect competition in markets with adverse selection this paper proposes a perfectly competitive model of a market with adverse selection prices are determined by zero profit conditions and the set of traded contracts is determined by free entry crucially for applications contract characteristics are endogenously determined consumers may have multiple dimensions of private information and an equilibrium always exists equilibrium corresponds to the limit of a differentiated products bertrand game we apply the model to establish theoretical results on the equilibrium effects of mandates mandates can increase efficiency but have unintended consequences with adverse selection an insurance mandate reduces the price of low coverage policies which necessarily has indirect effects such as increasing adverse selection on the intensive margin and causing some consumers to purchase less coverage

the cyclical behavior of monthly nymex energy prices abstract this paper systematically investigates the basic stylized facts of energy price movements using monthly data for the period that energy has been traded on organized exchanges and the methodology suggested by kydland and prescott kydland f e prescott e c 1990 business cycles real facts and a monetary myth fed reserve bank minneapolis q rev spring 3 18 the results indicate that energy prices are in general procyclical in contrast to the accepted fact that energy prices are countercyclical and leading the cycle

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

avoidable cost ride a double auction roller coaster the double auction trading institution has been highly efficient across diverse marginal cost market structures whether human subjects or zero intelligence robots populated those markets accordingly many researchers suspect that double auction performance transcends market structure and agent strategy but the authors show that large avoidable costs undermine the efficiency and stability of human subject double auctions and these low human efficiencies are simultaneously well above zero intelligence efficiencies their results dramatically illustrate the potential havoc wrought by highly competitive institutions when they must cope with nonconvex technologies copyright 1996 by american economic association

designing call auction institutions is double dutch the best this paper is an exercise in the institutional design of call markets schwartz i988 whitcomb i985 using the experimental laboratory as a test bed we evaluate the comparative performance1 of three new institutions for exchange when all trades are simultaneously executed at a uniform price call markets have been used on many european and israeli stock exchanges and for the daily opening on the new york american and tokyo stock exchanges in all outstanding listed issues in some versions the bids offers are verbal in others written in some cases the procedure is walrasian orders may be modified after a trial price is given whitcomb i985 also see jarecki i976 for the walrasian mechanism implemented with a unanimity stopping rule in the london bullion market in france new issues are offered in fixed quantity using modified uniform price sealed bid auction rules mcdonald and jaquillat i974 the rules of trading on all these exchanges are subject to incremental adjustment in the light of experience in recognition of this continuing adaptation the chicago mercantile exchange publishes its consolidated rules as a loose leaf three ring notebook these considerations motivate our interest in examining three potential new exchange mechanisms as their names suggest these institutions are generalisations of auctions which already exist in the field 2 double dutch dd is a generalisation of the dutch auction double english ee a generalisation of the english auction and dutch english de a special form of tatonnement using a single clock which is a dutch clock to buyers and an english clock to sellers our generalisations make the supply quantity endogenous thus broadening the scope of english and dutch auctions to markets in which both buyers and sellers are active in the exchange process two cited disadvantages of sealed bid offer call markets schwartz i988 pp 442 6 are corrected by

the approach of institutional economics this paper assesses the old institutional economics it emphasizes the importance of key old institutionalist themes concerning the necessity of habits and rules and the role of institutions a problem in the alternative theoretical program of the new institutionalism is the untenability of its assumption of an original institution free market or state of nature even optimizing behavior requires the prior existence of habits and rules although it still lacks a complete and systematic theory the evolutionary approach of the old institutionalists tackles the problem of the interactive relationship of actor to structure without analytical reduction to one or the other

costly offers and the equilibration properties of the multiple unit double auction under conditions of unpredictable shifts of demand and supply the paper reports on the behavior of markets in which a cost is imposed in the form of a tax on bids and asks but not contracts that are tendered in the market the markets were nonstationary in the sense that market demand and market supply shifted unpredictably in each period the results are as follows 1 a market equilibration process is observed across the periods of nonstationary markets 2 the price discovery process in the costly offer condition was incomplete relative to the free offer case 3 price equilibration with the offer cost was slower and efficiencies were reduced

geographical indications and the competitive provision of quality in agricultural markets the economics of geographical indications gis is assessed within a vertical product differentiation framework that is consistent with the competitive structure of agriculture it is assumed that certification costs are needed for gis to serve as collective credible quality certification devices and production of high quality product is endogenously determined we find that gis can support a competitive provision of quality and lead to clear welfare gains although they fall short of delivering the constrained first best the main beneficiaries are consumers producers may also accrue some benefit if production of the high quality products draws on scarce factors that they own copyright 2008 oxford university press

tradable deficit permits efficient implementation of the stability pact in the european monetary union tradable deficit permits efficient implementation of the stability pact borrowing from the experience of environmental markets this paper proposes a system of tradable deficit permits as an efficient mechanism for implementing fiscal constraints in the european monetary union having chosen an aggregate target for the union and an initial distribution of permits emu countries could be allowed to trade rights to deficit creation the scheme exploits countries incentives to minimize their costs is transparent and flexible in accommodating idiosyncratic shocks and allows for adjustments in case of europe wide recessions in addition it need not treat all countries identically and can be designed to penalize countries with higher debt to gdp ratios finally the scheme rewards countries for reducing their deficit below the initial allowance lending credibility to the stability pact s goal of a balanced budget in the medium run alessandra casella

follies subdued informational efficiency under adaptive expectations and confirmatory bias abstract we study the informational efficiency of a market with a single traded asset the price initially differs from the fundamental value about which the agents have noisy private information which is on average correct a fraction of traders revise their price expectations in each period the price at which the asset is traded is public information the agents expectations have an adaptive component and a social interactions component with confirmatory bias we show that taken separately each of the deviations from rationality worsens the informational efficiency of the market however when the two biases are combined the degree of informational inefficiency of the market measured as the deviation of the long run market price from the fundamental value of the asset can be non monotonic both in the weight of the adaptive component and in the degree of confirmatory bias for some ranges of parameters two biases tend to mitigate each other s effect thus increasing informational efficiency

a test of the modigliani miller invariance theorem and arbitrage in experimental asset markets modigliani and miller show that the total market value of a firm is unaffected by a repackaging of asset return streams to equity and debt if pricing is arbitrage free we investigate this invariance theorem in experimental asset markets finding value invariance for assets of identical risks when returns are perfectly correlated however exploiting price discrepancies has risk when returns have the same expected value but are uncorrelated in which case the law of one price is violated discrepancies shrink in consecutive markets but persist even with experienced traders in markets where overall trader acuity is high assets trade closer to parity

market stability backward bending supply in a laboratory experimental market 1999 presidential address western economic association the paper investigates the stability properties of markets with backward bending supply curves parameters are chosen so that the two classic models of price dynamics the walrasian model and the marshallian model give opposite predictions the results are 1 market instability can be observed 2 in the backward bending case stability is captured by the walrasian model and the marshallian model of dynamics is rejected previous experiments have demonstrated that the marshallian model works in the forward falling case thus which theory of dynamics is appropriate for a market depends upon the underlying reasons for demand and supply shapes

bounded rationality and the emergence of simplicity amidst complexity abstract the purpose of this essay is to explore the relationship between the simple and the complex in economics by anchoring our analysis on bounded rationality much of the conventional literature focuses on un bounded rationality of the rationality as consistency variety theorizing of bounded rationality tends to assume that the problem to be solved is independent of the nature of bounded rationality following the insights from the works of herbert simon and contributions from outside economics both bounded rationality and the environment are inextricably linked the boundaries between bounded rationality and its environment can shift the form in which bounded rationality is found depends on the complexity of the environment furthermore if local interactions between bounded rational agents result in the formation of hierarchies the complexity of the collective system will change whether this will occur depends on the nature of bounded rationality at the individual level

market clearing and price formation abstract considered here is decentralized exchange of privately owned commodity bundles voluntary transactions take the form of repeated bilateral barters under broad and reasonable hypotheses the resulting process converges to competitive equilibrium price taking behavior is not assumed prices emerge over time they need neither be anticipated nor known at any interim stage

oil and the macroeconomy when prices go up and down an extension of hamilton s results in an important paper hamilton 1983 demonstrated a strong correlation between oil price changes and gross national product growth in u s data however his study pertained to a period in which all the large oil price movements were upward and thus it left unanswered the question whether the correlation persists in periods of price decline moreover the price variable he used was somewhat distorted by price controls in the 1970s this note investigates whether hamilton s results continue to hold when the sample is extended to include the recent oil market collapse and the oil price variable is corrected for the effects of price controls particular attention is given to the possibility of asymmetric responses to oil price increases and decreases as suggested in the structural employment literature loungani 1986 davis 1987 hamilton 1988 like hamilton i based my investigation on the gnp equation in sims s 1 980b six variable quarterly vector autoregressive model