is protectionism on the rise assessing national trade policies during the crisis of 2008 to understand the role of trade policies in the crisis of 2008 this paper constructs the overall trade restrictiveness indices for a wide range of countries using their tariff schedules in 2008 and 2009 the index summarizes the trade policy stance of a country taking into account the share of each good in trade as well as its corresponding import demand elasticity results show that there is no widespread increase in protectionism via tariff policies since the global financial crisis has unfolded while many countries have adjusted tariffs upward on selected products only a handful of countries such as malawi russia argentina turkey and china focus on products that have significant impacts on trade flows the united states and the european union by contrast rely mainly on anti dumping duties to shield domestic industries overall while the rise in tariffs and anti dumping duties in these countries may have jointly caused global trade to drop by as much as us 43 billion during the crisis period it explains less than 2 percent of the collapse in world trade

how traders influence their neighbours modelling social evolutionary processes and peer effects in agricultural trade networks abstract marketing channel choices in agricultural trade networks affect the networks overall performance and influence rural livelihoods this study identifies key determinants of these choices among natural rubber traders in indonesia to evaluate four policy scenarios and their potential effects on rural incomes since traders marketing decisions are based on past interactions resulting trade networks are formed in recursive processes and can be understood as complex adaptive systems due to inherent endogeneity in these systems process based approaches such as agent based modelling abm can be effective in understanding them using a self gathered primary dataset from jambi province indonesia we implement and parameterise an abm to simulate the formation of the rubber trading network and analyse the effects on rural livelihoods of four hypothetical policy scenarios improved micro credit availability increased access to education better infrastructure and transportation capacity and market information availability the model is calibrated through a genetic algorithm which maximises the similarity between the simulated network and the actual network observed in the data results indicate that sellers decisions on a buyer are primarily determined by debt obligations and past peer interactions the most influential sellers have a similar level of formal education as their peers and live in close physical proximity results of the policy scenario analysis suggests that policies aimed at reducing sellers dependence on credit from buyers and increasing education are the most effective policies for improving value chains and reducing poverty in the region under consideration

land degradation drought and food security in a less favoured area in the ethiopian highlands a bio economic model with market imperfections abstract this paper presents a bio economic model of andit tid a severely degraded crop livestock farming system with high population density and good market access in the highlands of ethiopia land degradation population growth stagnant technology and drought threaten food security in the area drought or weather risk appears to have increased in recent years the bio economic model is used to analyse the combined effects of land degradation population growth market imperfections and increased risk of drought on household production welfare and food security we find that the indirect effects of drought on household welfare through the impact on crop and livestock prices are larger than the direct production effects of drought provision and adoption of credit for fertiliser although risky in itself may lead to increased grain production and improved household welfare and food security provision of credit may have a negative effect on conservation incentives but this effect may be mitigated by linking a conservation requirement to the provision of credit for fertiliser

protection with static collusion the present paper argues that when static collusion takes place there is a new justification for a tariff this occurs in the context of a model in which consumers observe prices at a cost and the industry structure is a duopoly with a home and a foreign firm because costly search induces imperfect information about prices on the part of consumers the ability to rapidly revise posted prices on the part of the duopolists leads to the appropriation of a substantial amount of consumer surplus the static collusion takes place under any trade policy thus a home tariff that shifts a duopoly equilibrium to the advantage of the home firm will be demonstrated to entail in the case of a nonprohibitive tariff no consumption cost from protection because this tariff generates revenue for the home government and greater profits for the home firm it will be welfare improving to the home country the concept of profit shifting as a motive for commercial policy in imperfectly competitive markets was pioneered by brander and spencer 6 2 in a model where home and foreign duopolists are nash courot competitors a tariff can shift profits from the foreign to the home firm by inducing the foreign firm to play less aggressively in the present paper the tariff shifts profits within the collusive outcome by precluding more aggressive play by the foreign firm 3 furthermore davidson 8 has disclosed that the level of a tariff can affect the incentives to collude in a quantity setting supergame with nash cournot punishments in the present model the tariff affects the collusive outcome that can be supported it does not however affect the incentives to collude

a political economy theory of trade agreements we develop a model where trade agreements in addition to correcting terms of trade externalities help governments to commit vis a vis domestic industrial lobbies the model allows us to explore how the characteristics of the political environment aect the structure of the trade agreement and the extent of trade liberalization the model also highlights the role of intersectoral capital mobility in determining trade liberalization in a dynamic extension of the model we explore the extent to which trade liberalization occurs gradually and how its speed depends on the fundamentals of the problem

unemployment and rationality the explanation of persistent excess labor supply is a challenge to macroeconomic theorists in a purely competitive framework it may be argued that unemployment is transitory since wages will react if excess supply is persistent enough for the economy to be driven towards full employment nevertheless classical tatonement models do not support this view since excess demand functions are arbitrary see shafer and sonnenschein 1982 and convergence to the walrasian equilibrium cannot be guaranteed fixed price theory accounts for unemployment at the cost of total indeterminacy of equilibrium allocations many efforts have been made in order to narrow down this set roughly speaking these attempts can be classified into two groups i the conjectural approach cf benassy 1976 negishi 1974 grandmont and laroque 1976 and hahn 1977 1978 ii the game theoretical approach cf hart 1982 madden 1983 and silvestre 1988 in this paper we want to contribute to the first tine of thinking by applying the rationality notion developed for a conjectural equilibrium model in trujillo 1985 to a standard three goods fixed price model both kinds of equilibria are equivalent see john 1985 the motivation behind our approach is that when agents set prices they have to respect the rules of the mechanism for instance in hahn s rationality approach agents may change prices even if they are not constrained however the assumed mechanism is such that this behavior is not allowed see below therefore agents must be cheating le hahn s notion is one of incentive compatibility and it is not surprising that he obtained negative results in our approach agents may change prices if they are conjecturable in the following sense if buyers are rationed they can increase conjecture higher prices and if sellers are constrained

rules communication and collusion narrative evidence from the sugar institute case detailed notes on weekly meetings of the sugar refining cartel show how communication helps firms collude and so highlight the deficiencies in the current formal theory of collusion the sugar institute did not fix prices or output prices were increased by homogenizing business practices to make price cutting more transparent meetings were used to interpret and adapt the agreement coordinate on jointly profitable actions ensure unilateral actions were not misconstrued as cheating and determine whether cheating had occurred in contrast to established theories cheating did occur but sparked only limited retaliation partly due to the contractual relations with selling agents jel l13 l41 this paper reexamines the cartel problem by studying the private discussions within one cartel while we find much that is in accord with george j stigler s 1964 basic insight that firms would structure an agreement conscious of their later incentive to cheat on it we also uncover puzzles for established theory and identify elements that a richer theory should encompass especially regarding the role of communication in collusion our window into the inner workings of a cartel is a remarkable series of notes on the weekly meetings of the sugar institute this trade association was formed in december 1927 in the wake of several years of falling margins and excess capacity by 14 firms comprising nearly all the cane sugar refining capacity in the united states it operated until 1936 when the supreme court ruled its practices illegal among the top executives in regular attendance at the meetings was louis v place vice president of mccahan a midsize refinery in philadelphia place who was in charge of all activities of the company except production and raw sugar purchases wrote over 500 pages of single spaced detailed

on the generic inefficiency of differentiable market games it is shown that a differentiable market game remains generically inefficient when its strategic outcome function is perturbed smoothly the proof is based on thom s transversality theorem and removes any restriction regarding the dimension of the strategy spaces a converse result is that almost all efficient market games that are competitive are characterized by bertrand like non differentiabilities finally a synthesis between the cournot and bertrand type approaches to walrasian equilibrium as recently developed in the literature is suggested

the objective demand curve in general equilibrium with price makers objective demand curves in general equilibrium with explicitly modeled price makers have been defined so far in a number of specific cases this paper gives a general definition of such an objective demand curve the associated general equilibrium concept is defined and sufficient existence conditions are given copyright 1987 by royal economic society

approaches to the privatization of fertilizer marketing in africa abstract agricultural marketing privatization has been a central feature of structural adjustment recommendations this paper briefly analyses the main issues related to privatization in the fertilizer sector in africa reviews developments and examines possible reasons for the relatively slow progress to date constraints to effective privatization are identified and policy changes and other reforms necessary if fertilizer marketing privatization is to succeed are proposed effective privatization will not be achieved without detailed planning and consideration of potential problems at an early stage

revocable pricing can yield collusive outcomes abstract traditional models of bertrand price competition assume irrevocable price announcements in contrast when price changes have zero direct costs but sales are thereby delayed the collusive monopoly outcome is a subgame perfect outcome and is moreover the natural focal equilibrium

the smoot hawley tariff a quantitative assessment in the two years after the imposition of the smoot hawley tariff in june 1930 the volume of u s imports fell over 40 to what extent can this collapse of trade be attributed to the tariff itself versus other factors such as declining income or foreign retaliation partial and general equilibrium assessments indicate that the smoot hawley tariff itself reduced imports by 4 8 ceteris paribus although the combination of specific duties and deflation further raised the effective tariff and reduced imports an additional 8 10 a counterfactual simulation suggests that nearly a quarter of the observed 40 decline in imports can be attributed to the rise in the effective tariff i e smoot hawley plus deflation

dealing with uncertainty in agent based simulation farm level modeling of adaptation to climate change in southwest germany climate change will most likely confront agricultural producers with natural economic and political conditions that have not previously been observed and are largely uncertain as a consequence extrapolation from past data reaches its limits and a process based analysis of farmer adaptation is required simulation of changes in crop yields using crop growth models is a first step in that direction however changes in crop yields are only one pathway through which climate change affects agricultural production a meaningful process based analysis of farmer adaptation requires a whole farm analysis at the farm level we use a highly disaggregated mathematical programming model to analyze farm level climate change adaptation for a mountainous area in southwest germany regional level results are obtained by simulating each full time farm holding in the study area we address parameter uncertainty and model underdetermination using a cautious calibration approach and a comprehensive uncertainty analysis we deal with the resulting computational burden using efficient experimental designs and high performance computing we show that in our study area shifted crop management time slots can have potentially significant effects on agricultural supply incomes and various policy objectives promoted under german and european environmental policy schemes the simulated effects are robust against model uncertainty and underline the importance of a comprehensive assessment of climate change impacts beyond merely looking at crop yield changes our simulations demonstrate how farm level models can contribute to a process based analysis of climate change adaptation if they are embedded into a systematic framework for treating inherent model uncertainty

imperfect competition in auction designs we study the competition between two owners of identical goods who wish to sell them to a pool of potential buyers the sellers compete simultaneously setting reserve prices for their second price sealed bid auctions upon observing the set reserve prices the buyers decide simultaneously in which auction to bid we show that this game has at least one equilibrium and that all equilibria are inefficient reserve prices are not driven to zero cost we also discuss where and why the parallel between optimal auction design and optimal pricing in the case of monopoly breaks down for oligopoly

competitivity in auction markets an experimental and theoretical investigation the authors report successive rounds of theory and laboratory experiments investigating price taking behavior and market efficiency they focus on the impact of structural parameters as well as trading institution the structural parameters involve noncompetitive supply and demand and a new odd lot trading procedure for divisible goods the trading institutions include the continuous double auction and the one shot clearinghouse as well as a new quantities only clearinghouse institution the authors present and justify an as if complete information theory that explains the competitive outcomes and that correctly predicts highly noncompetitive outcomes in quantities only clearinghouse markets copyright 1995 by royal economic society

protectionism during the crisis tit for tat or chicken games abstract we explore the extent to which the adoption of protectionist measures during the recent financial crisis led to retaliation by trading partners we find no evidence of retaliation on the contrary there is strong evidence of chicken games being played

are rational conjectures rational the concepts of rational conjectures and reasonable conjectures are critically reviewed it is shown that their operation depends crucially on an invisible non optimizing deus ex machina hence these concepts are not really suitable for understanding competition among optimizing firms in addition the widely claimed fact that bertrand conjectures are locally rational conjectural variations is shown to be erroneous the message of this paper should be plain from the title it reflects a disillusionment with the concepts of rational conjectures and reasonable conjectures for helping us understand economic interactions under imperfect competition on the face of it these concepts seem to offer the economic modeller some useful tools hence this paper is in some sense intended as a friendly warning to other economic modellers there are inherent conceptual weaknesses in these concepts that do not become apparent until one begins to penetrate their inner logic to make plain the weaknesses of rational conjectures and reasonable conjectures we shall concentrate on the simplest application of the ideas to duopoly and we shall illustrate our points using the classical cournot example of duopolists facing a common linear demand curve and having the same constant marginal cost the reader may know that this example figures prominently in the rational conjectures literature it being shown that bertrand conjectures are locally rational conjectural variations we shall see in section vi that this claim is not really valid although widely asserted but our real message is on a different plane and pertains to the usefulness of the concepts in general

promoting high input maize technologies in africa the sasakawa global 2000 experience in ethiopia and mozambique abstract critics argue that high external input technologies heit are too costly for african farmers and that programs to promote them are economically unsustainable this paper assesses sasakawa global 2000 programs in ethiopia and mozambique using financial and economic analysis yield models and subsector analysis the sg 2000 technology was much more profitable in ethiopia than in mozambique but varied depending on production location fertilizer and transport costs domestic and international prices regional surplus or deficit conditions and production as import substitute or export the case studies provide further evidence that high input technologies can be successfully introduced through well funded high profile programs but not conclusive evidence that such programs can be scaled up and sustained five major implications are discussed concerning 1 prospects for scaling up and sustaining heit adoption 2 the need for expanded profitability analysis 3 the role of trade prospects and policies 4 institution building requirements and 5 infrastructure investments to reduce marketing costs

fertilizer market development a comparative analysis of ethiopia kenya and zambia abstract this article synthesizes case studies from kenya zambia and ethiopia to assess how differences in the implementation of fertilizer marketing policies have affected the costs and risks borne by marketing actors the investment response by private traders and fertilizer consumption financial cost accounting techniques indicate that domestic marketing costs account for 50 or more of farm gate prices the sum of importer wholesaler and retailer profit margins generally account for less than 10 there are opportunities to reduce domestic marketing costs through the following reducing port fees coordinating the timing of fertilizer clearance from the port with up country transport reducing transport costs through port rail and road improvements reducing high fuel taxes and reducing the uncertainty associated with government input distribution programs that impose additional marketing costs on traders estimated reductions in the farm gate price of fertilizer from implementing the full range of options identified in each country range from 11 to 18 price reductions of this magnitude if passed along to farmers would increase farmers effective demand for fertilizer investments in selected publically provided goods often considered outside the scope of fertilizer marketing policy per se strongly affect the costs of fertilizer farmers willingness to pay for it and hence the performance of markets

feasible and continuous implementation there has been a great deal of research in recent years investigating the question of whether or not there exist institutions game forms for which the set of equilibria will coincide with the set of walrasian equilibria in this paper we show the existence of a game form that is feasible both for equilibrium and disequilibrium strategies continuous and for which the set of nash equilibria coincides with the set of constrained walrasian equilibria for all pure exchange economies the game form allows agents to behave strategically both with respect to their preferences and their initial endowments

quick responses in duopoly ensure monopoly pricing if firms in a homogeneous duopoly game can respond with negligible delay to their rival s price changes equilibrium is unique at the monopoly price

smart policies to reduce pesticide use and avoid income trade offs an agent based model applied to thai agriculture abstract policy makers in developing countries need better evidence of how changes in pesticide regulation would affect pesticide reduction and farm incomes but there are very few modeling tools that can provide such information the present study develops a new model based on mathematical programming based multi agent system mpmas a simulation software that allows assessing ex ante the impact of alternative pesticide use reduction strategies including combinations of pesticide taxes the introduction of integrated pest management a price premium for safe agricultural produce and subsidies for biopesticides the model is parameterized with farm and plot level data from northern of thailand where the adoption of high value cash crops has been accompanied by a rapid increase in synthetic pesticide use simulation results suggest that a pesticide tax alone has little effect on synthetic pesticide use a smart policy package combining integrated pest management a progressive pesticide tax based on toxicity and subsidies lowering the price of biopesticides can reduce average use of hazardous pesticides by 34 over current levels without adverse effects on the average farm income

perfectly flexible pricing in a homogeneous market so as to present our reappraisal of the implications of perfect price flexibility in the simplest possible framework we turn to marshall s 1920 book v corn market example where stocks offered for sale already exist at the outset and where equilibrium is established solely through price adjustment in this context marshall simply took it for granted that the competitive price is the unique equilibrium price op cit p 278 indeed it is clear that if prices are set by the sellers and no seller can change a quoted price then a uniform price above the competitive

strategy proof risk sharing abstract we consider risk sharing problems with a single good and a finite number of states agents have a common prior and their preferences are represented in the expected utility form and are risk averse we study efficient and individually rational risk sharing rules satisfying strategy proofness the requirement that no one can ever benefit by misrepresenting his preference when aggregate certainty holds we show that fixed price selections from walrasian correspondence are the only rules satisfying efficiency individual rationality and strategy proofness however when aggregate uncertainty holds we show that there exists no rule satisfying the three requirements moreover in the two agents case we show that dictatorial rules are the only efficient and strategy proof rules dropping the common prior assumption in the model we show that this assumption is necessary and sufficient for the existence of rules satisfying the three main requirements in the two agents and aggregate certainty case

testing a model of the kinked demand curve this paper analyzes survey data on the responses firms expect from their competitors when they change prices there is evidence of an assymmetry in expected responses which provides some support for modified versions of the kinked demand curve the asymmetry in responses is found to be cyclically sensitive and to differ with certain firm characteristics copyright 1991 by blackwell publishing ltd

linear inequality methods to enforce partnerships under uncertainty an overview we review different generic conditions on stochastic outcome functions to enforce either efficient or nearly efficient partnerships their logical relationship is explored two kinds of conditions are considered however the property for an action profile to be compatible plays a crucial role in both kinds also two kinds of enforcement mechanisms are considered enforcement through utility transfers and enforcement through repetition

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

technical coefficients for bio economic farm household models a meta modelling approach with applications for southern mali abstract in recent years different types of bio economic models have been developed to support the analysis of the potential impact of agrarian policies on changes in land use sustainable resource management and farmers welfare most bio economic models rely on series of discrete input output coefficients for current and improved cropping and livestock activities whereas mathematical programming procedures are usually applied to analyse optimum allocative choice adequate procedures for the smooth integration of biophysical information into economic decision models are however not readily available this article provides a new and comprehensive framework for the incorporation of technical input output coefficients derived from agroecological simulation approaches into bio economic farm household models therefore continuous production functions are estimated for the production side of the farm household model making use of meta modelling principles it is shown that meta modelling offers considerable scope for improving the specification and behaviour of bio economic farm household models this procedure is applied in a farm household model developed for the analysis of farmers response to agrarian policies in southern mali results are presented for the behaviour of a typical household focusing attention on the trade offs between farm income and soil nutrient balances under free market conditions and with constraints on labour capital and animal traction markets the stability and robustness of the model is analysed through a simulation of the impact of higher input costs for land use and fertiliser applications

on the status of the nash type of noncooperative equilibrium in economic theory in economic theory the nash type of noncooperative equilibrium is a widely used equilibrium concept nevertheless the concept is frequently misunderstood and misleading explanations and interpretations are often given this paper presents a sample of such frequently appearing misleading explanations and goes on to explain why they are misleading the case for using the nash noncooperative equilibrium concept is stronger than what is implied by the many misleading statements found in the literature a basic issue is whether it can be argued that decisions in accordance with the noncooperative equilibrium theory are individually rational decisions this issue is not covered by the classical rationality postulate in economic theory this problem is tackled by stating certain postulates which may be taken as defining individual rationality in situations of noncooperative interaction it is shown that nash behavior satisfies these postulates

the kinked demand curve a game theoretic approach in a simple model of duopoly firms price moves are modelled as an extensive form game where firms can respond to undercutting without delay when firms are not too dissimilar kinked demand strategies enforcing an arbitrary price may be nash equilibria however these strategies are dominated and perfect equilibrium is unique at the minimum optimal common price rather than implying price rigidity kinked demand strategies are a device for ensuring compliance with a collusive price leadership

simulating the diffusion of organic farming practices in two new eu member states abstract agriculture continues to be a major contributor to water pollution climate change and loss of biodiversity although policies to encourage farmers to work to higher sustainability standards in food and energy crop production have increased throughout the european union in new member states accession to the european union mostly brought a substantially increased public support to foster the diffusion of certified organic farming however the take up of organic farming is varied for reasons that are not yet well understood in this paper we analyse the diffusion of organic farming through farm populations this involves an understanding of farmer behaviour and how it can change over time we present a generic agent based model that builds on the theory of planned behaviour as framework for understanding and modelling farmers decision making processes the model is applied to high diffusion regions in two new eu member states latvia and estonia the values for the model s parameters are informed by survey data the model reproduces the interdependence of social influence and economic factors social influence alone is shown to make little difference to the model dynamics organic farmers remain organic and conventional farmers remain conventional introducing a change to the environment e g a subsidy results in an increase in the proportion of adopters thus economic factors appear to be more influential than social factors however only when allowing for both the subsidy and social influence do we reveal the whole picture and the combined adoption rate is higher than the sum of the proportion of adopters resulting from just social influence without a subsidy and from just a subsidy without social influence we also compare the effect of the subsidy with the effect of influence from organic farm advisors to develop policy recommendations

hidden protectionism evidence from non tariff barriers to trade in the united states abstract can the enforcement of product standards be protectionism in disguise this paper estimates the costs of non compliance with u s product standards using a new database on u s import refusals from 2002 to 2014 we find that import refusals decrease exports to the united states this trade reducing effect is driven by developing countries and by refusals without any product sample analysis in particular during the subprime crisis and its aftermath we also provide evidence that given product standards were enforced more strictly during the crisis while the quality of imported products did not deteriorate these results are consistent with the existence of counter cyclical hidden protectionism due to non tariff barriers to trade in the united states

input use and market development in sub saharan africa an overview abstract this paper sets forth the background and objectives of this special issue trends in input use since 1980 are reviewed and a conceptual framework is presented for analyzing problems of input use and formulating strategies for resolving them reasons for low levels of fertilizer use by smallholder farmers are summarized briefly the essential points of the papers in the special issue and their implications for further expansion of input use in sub saharan africa are then outlined

general equilibrium concepts under imperfect competition a cournotian approach in a pure exchange economy we propose a general equilibrium concept under imperfect competition the cournotian monopolistic competition equilibrium and compare it to the cournot walras and the monopolistic competition concepts the advantage of the proposed concept is to require less computational ability from the agents the comparison is made first through a simple example then through a mon abstract concept the p equilibrium based on a general notion of price coordination c 1997 academic press

technological and policy options for sustainable agricultural intensification in eastern uganda this article presents a bio economic household model which has been developed to assess the potential impacts of agricultural intensification efforts on economic and ecological indicators in eastern uganda a study region in the lake victoria crescent was selected with comparative advantages for intensive agricultural production high agricultural potential high market access and high population density however current production is characterized by low input output systems revealing a discrepancy between development opportunities and actual development outcomes based on a farmer participatory research approach production methods were introduced in the study region aimed at fostering sustainable agricultural development data from two community surveys two comprehensive household and plot level surveys and farm trial data were used to develop and calibrate bio economic models for four representative household types model scenarios reveal that farm households in eastern uganda would not pursue sustainable intensification under current socio economic conditions the market environment has to be improved substantially i e transaction and transportation costs have to be reduced innovative credit schemes for smallholders have to be introduced and alternative forms of labor acquisition have to be promoted to provide sufficient economic incentives for the adoption of environmentally sound production methods in addition agricultural service provision needs to be reformed and more agricultural research is needed for new and better targeted technologies

agent based spatial models applied to agriculture a simulation tool for technology diffusion resource use changes and policy analysis abstract this paper presents a spatial multi agent programming model which has been developed for assessing policy options in the diffusion of innovations and resource use changes unlike conventional simulation tools used in agricultural economics the model class described here applies a multi agent cellular automata ca approach by using heterogeneous farm household models and capturing their social and spatial interactions explicitly the individual choice of the farm household among available production consumption investment and marketing alternatives is represented in recursive linear programming models adoption constraints are introduced in form of network threshold values that reflect the cumulative effects of experience and observation of peers experiences the model s economic and hydrologic components are tightly connected into a spatial framework the integration of economic and hydrologic processes facilitates the consideration of feedback effects in the use of water for irrigation the simulation runs of the model are carried out with an empirical data set which has been derived from various data sources on an agricultural region in chile simulation results show that agent based spatial modelling constitutes a powerful approach to better understanding processes of innovation and resource use change

the collapse of global trade a unique feature of the financial crisis is the unprecedented collapse in global world trade the objective of this paper is to explain some of that collapse as a move towards protectionism triggered not by nationalistic interests but by competing objectives among trading partners from the mundell fleming trilemma even with the best of intentions efforts towards internal rebalancing necessarily imply harming your trading partner unintentionally if they should be using conflicting policy objectives of the trilemma national interests are at odds between two such countries and their policy prescriptions counteract and paralyse rebalancing and coordination efforts between nations policymakers may be forced into protectionist stances in an effort to counteract the internal rebalancing efforts of their neighbours

reducing dependence on chemical fertilizers and its financial implications for farmers in india the fertilizer intensive technology so long promoted in agriculture produced a green revolution but has brought long term damages to soil quality the technology now appears unsustainable for future agricultural development in india both on account of its ecological implications and the burden on the budget there is now a need to revisit the traditional methods once used in agriculture and to look for a judicious blend of chemical fertilizer based technology with organic manure since manures are relatively less productive in the short run there is an alarm that a shift in technology away from the chemical fertilizer towards organic manure may mean a compromise in production or may hurt the incomes of farmers this paper emphasizes the environmental benefits of a possible shift in agricultural technology while keeping in view the importance of sustaining crop yield levels and protecting farmers incomes considering two major crops in india in specific states the paper finds that over time while fertilizer use intensified several times over the use of manure in agriculture either stagnated or declined the manure market remained localized limited and unorganized and its price was significantly higher than fertilizer in terms of nutrients in contrast to the organized and state supported fertilizer market the paper estimates quadratic yield functions based on cross section household level data and using the prices faced by farmers as reported by official survey finds that in majority of the cases there will not be any financial loss resulting from a small shift in technology towards organic manure such a shift can however be considered feasible if the losing households are compensated and if manure price is kept in control by promoting a more dynamic manure market d 2004 elsevier b v all rights reserved

simulating soil fertility and poverty dynamics in uganda a bio economic multi agent systems approach declining soil fertility and increasing rural poverty are major problems facing sub saharan agriculture bio economic modeling has been used to analyze the complex interaction between ecological sustainability and rural poverty as well as to explore policy options promoting sustainable development this paper shows that these models can be further advanced by adopting an agent based modeling approach this gives a more realistic representation of diversity in socioeconomic and biophysical terms allows local interaction between households and can yield an ex ante assessment of the distributional consequences of policy intervention this paper describes the modeling approach and illustrates it with an empirical application to two village communities in the lake victoria crescent of uganda it is shown how the model system can be calibrated with and validated against empirical data the model is used to analyze the potential effect of short term credit mineral fertilizer and improved maize seed on poverty and sustainability simulation results suggest substantial reductions in poverty although the incidence of poverty would remain high and these innovations alone would have little effect on the long term ecological sustainability of the system

agent based modeling for ex ante assessment of tree crop innovations litchis in northern thailand this study uses an agent based model for ex ante assessment of agricultural innovations the model builds on whole farm mathematical programming mp and extends the methodology with a spatial representation of the system the heterogeneity of farm households and landscapes and the interaction between farm households we apply the model in a northern thai watershed to study the potential of four innovations to increase the profitability of litchi orchards cost benefit analysis shows that each innovation would increase the profitability of litchi growing however the results of the agent based model show that at current price levels these innovations alone would not be enough to stem the decline in the area under litchis the model was validated and the sensitivity of the results tested for variations in the irrigated water supply and liquidity we report on how farmers responded to these results and discuss the implications for other areas in northern thailand