A review of Multi-Agent Simulation Models in Agriculture

Multi-Agent Simulation (MAS) models are intended to capture emergent properties of complex systems that are not amenable to equilibrium analysis. They are beginning to see some use for analysing agricultural systems. The paper reports on work in progress to create a MAS for specific sectors in New Zealand agriculture. One part of the paper focuses on options for modelling land and other resources such as water, labour and capital in this model, as well as markets for exchanging resources and commodities. A second part considers options for modelling agent heterogeneity, especially risk preferences of farmers, and the impacts on decision-making. The final section outlines the MAS that the authors will be constructing over the next few years and the types of research questions that the model will help investigate.multi-agent simulation models, modelling, agent-based model, cellular automata, decision-making, Crop Production/Industries, Environmental Economics and Policy, Farm Management, Land Economics/Use, Livestock Production/Industries,

Adaptive microfoundations for emergent macroeconomics

In this paper we present the basics of a research program aimed at providing microfoundations to macroeconomic theory on the basis of computational agentbased adaptive descriptions of individual behavior. To exemplify our proposal, a simple prototype model of decentralized multi-market transactions is offered. We show that a very simple agent-based computational laboratory can challenge more structured dynamic stochastic general equilibrium models in mimicking comovements over the business cycle.Microfoundations of macroeconomics, Agent-based economics, Adaptive behavior

Spatial interactions in agent-based modeling

Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution of economic activities, - out of equilibrium. The Eurace@Unibi Model, an agent-based macroeconomic model with spatial structure, is used to illustrate the potential of such an approach for spatial policy analysis.Comment: 26 pages, 5 figures, 105 references; a chapter prepared for the book "Complexity and Geographical Economics - Topics and Tools", P. Commendatore, S.S. Kayam and I. Kubin, Eds. (Springer, in press, 2014

Addressing food self-sufficiency in Tanzania: a balancing act of policy coordination

This paper examines the performance of food production and productivity in Tanzania since 2000, in relation to post-SAP policies. This discussion assumes that individual households in Tanzania strive to achieve food security through own production as well as purchases from the market. Meanwhile, the government strives to meet national food self-sufficiency of main staples (maize,rice and cassava) from local production, implying that individual farmers must produce a surplus, which is then marketed efficiently so that everybody can access sufficient and good-quality food at all times at affordable prices. Any change in the policy environment changes the opportunity set and hence the choices individuals make, which in turn shapes the aggregate performance of economies over time (North, 1993). It is in this context that the analysis in this paper looks at the performance of food production and marketing, at the micro and macro levels, during the post-SAP period in Tanzania, as influenced by preceding and prevailing policies and institutions, in particular focusing on the magnitude and direction of change. The discussion is guided by several questions: is there any change happening in food production? What is driving that change? Can the change be sustained? What is the role of supporting institutions, markets and governance in directing this change?Tanzania; Food security; market failure; policy review; sokoine university of agriculture

Asset-based measurement of poverty

Poverty is generally defined as income or expenditure insufficiency, but the economic condition of a household also depends on its real and financial asset holdings. This paper investigates measures of poverty that rely on indicators of household net worth. We review and assess two main approaches followed in the literature: income-net worth measures and asset-poverty. We provide fresh cross-national evidence based on data from the Luxembourg Wealth Study.poverty indicators, income, wealth

Optimizing Credit Limit Adjustments Under Adversarial Goals Using Reinforcement Learning

Reinforcement learning has been explored for many problems, from video games with deterministic environments to portfolio and operations management in which scenarios are stochastic; however, there have been few attempts to test these methods in banking problems. In this study, we sought to find and automatize an optimal credit card limit adjustment policy by employing reinforcement learning techniques. In particular, because of the historical data available, we considered two possible actions per customer, namely increasing or maintaining an individual's current credit limit. To find this policy, we first formulated this decision-making question as an optimization problem in which the expected profit was maximized; therefore, we balanced two adversarial goals: maximizing the portfolio's revenue and minimizing the portfolio's provisions. Second, given the particularities of our problem, we used an offline learning strategy to simulate the impact of the action based on historical data from a super-app (i.e., a mobile application that offers various services from goods deliveries to financial products) in Latin America to train our reinforcement learning agent. Our results show that a Double Q-learning agent with optimized hyperparameters can outperform other strategies and generate a non-trivial optimal policy reflecting the complex nature of this decision. Our research not only establishes a conceptual structure for applying reinforcement learning framework to credit limit adjustment, presenting an objective technique to make these decisions primarily based on data-driven methods rather than relying only on expert-driven systems but also provides insights into the effect of alternative data usage for determining these modifications.Comment: 29 pages, 16 figure

Modeling the fiscal impacts caused by climate change

Aim of the paper: The purpose is to gather the practices and to model the impacts of climate change on fiscal spending and revenues, responsibilities and opportunities, balance and debt related to climate change (CC). Methodology of the paper: The methodology will distinguish fiscal cost of mitigation and adaptation, besides direct and indirect costs. It will also introduce cost benefit analyses to evaluate the propensity of policy makers for action or passivity. Several scenarios will be drafted to see the different outcomes. The scenarios shall contain the possible losses in the natural and artificial environment and resources. Impacts on public budget are based on damage of income opportunities and capital/wealth/natural assets. There will be a list of actions when the fiscal correction of market failures will be necessary. Findings: There will be a summary and synthesis of estimation models on CC impacts on public finances, and morals of existing/existed budgeting practices on mitigation. The model will be based on damages (and maybe benefits) from CC, adjusted with probabilities of scenarios and policy making propensity for action. Findings will cover the way of funding of fiscal costs. Practical use, value added: From the synthesis of model, the fiscal cost of mitigation and adaptation can be estimated for any developed, emerging and developing countries. The paper will try to reply, also, for the challenge how to harmonize fiscal and developmental sustainability

A New Framework for African Economic Development with a Focus on Technological Innovation

Based on a brief review of the development paradigm shifts, growth theories and perspectives that have influenced four decades of African economic development, this paper suggests that the challenges confronting African development result primarily from continuously shifting paradigms and inconsistent growth policies that neglect the role of technological innovation. Moreover, given these challenges, achieving rates of GDP per capita change that result in an increase in average income over a long period will demand an emphasis on and adoption of technological innovation and R&D, as well as corresponding education policies. In terms of perspective, the survival of African countries in the twenty-first century undoubtedly depends on the continent‘s ability to apply existing scientific and technological knowledge to the achievement of economic growth, income distribution and environmental protection. Engineering the complementarity among these three objectives will require not only institutional and structural adjustments and technological innovation and adoption but also a culture of innovation that most parts of Africa do not currently perceive as a crucial factor for social change.Economic Development; Africa; Technology; Development Paradigms