spatial equilibrium models

Marietto, M., David, N., Sichman, J. and Coelho, H. 2003. Requirement analysis of agent-based simulation platforms: State of the art and new prospects. Lecture Notes in Artificial Intelligence:125-141.

Parker, D., Berger, T. and Manson, S., editors. 2002. Agent-based models of land-use and land-cover change. LUCC Report Series, 6, Indiana University.

Petit, O. 2001. Combining mas with gis: Another way to "pixelise" the commons? The Common Property Resource Digest. Quaterly Publication of the international association for the study of common property:9-11.

Röling, N. 1999. Modelling the soft side of the land: The potential of multi-agent systems. Pages 73-97 in C. Leeuwis, editor. Integral design: Innovation in agriculture and resource management. Mansholt Instituu te, Wageningen.

Mertens and Lambin, 2000. land cover-change trajectories in southern cameroon. annals of the association of american geographers, 93, 467-494. (um modelo economico)

H V. D. Parunak and S. A. Brueckner and R. Matthews and J. Sauter, 2006

Geospatial data are often used to predict or recommend movements of robots, people, or animals (‘walkers’). Analysis of such systems can be combinatorially explosive. Each decision that a walker makes generates a new set of possible future decisions, and the tree of possible futures grows exponentially. Complete enumeration of alternatives is out of the question. One approach that we have found promising is to instantiate a large population of simple computer agents that explore possible paths through the landscape. The aggregate behaviour of this swarm of agents estimates the likely behaviour of the real-world system. This paper will discuss techniques that we have found useful in swarming geospatial reasoning, illustrate their behaviour in specific cases, compare them with existing techniques for path planning, and discuss the application of such systems.

P. A. Graniero and V. B. Robinson, 2006

Many environmental, ecological, and social problems require investigation using a mixture of landscape models, individual-based models, and some level of interaction between them. Few simulation-modelling frameworks are structured to handle both styles of model in an integrated fashion. ECO-COSM is a framework that is capable of handling complex models with both landscape and agent components. Its Probe-based architecture allows model components to have controlled access to the state of other components. The ProbeWrapper is a modification of this common design approach which allows alterations to the state retrieved from the model and is a critical component of ECO-COSM’s broad modelling capability. It allows agents to apply perceptual filters or measurement errors to their observations of the landscape, or apply decisionmaking strategies in the face of incomplete or uncertain observations. ECOCOSM is demonstrated with a landscape model of metapopulation dynamics, an agent model of squirrel dispersal, and a coupled landscape-agent model to evaluate field-data-acquisition strategies for identifying nutrient or contaminant hotspots.

Border topology: wrapping, reflecting or hard (default?)

J. Hindriks, 1999

In a context where both the poor and the rich are (imperfectly) mobile, this paper compares the Nash equilibrium levels of income redistribution from the rich to the poor when jurisdictions compete either in taxes, in transfers or both in taxes and transfers. Although taxes and transfers are linked through the budgetbalanced requirement, the analysis reveals intriguing differences. Indeed, it turns out that transfer competition results in much less redistribution than tax competition, while taxtransfer competition involves an intermediate level of redistribution. In each approach, the mobility of the rich is detrimental to redistribution and an increase in the dependency ratio reduces taxes. Concerning the effect of the mobility of the poor, these approaches reach opposite conclusions. That is, the mobility of the poor is beneficial to redistribution under tax competition but reduces redistribution under transfer competition.

G. M. and Y. Y. Papageorgiou, 1997

We consider a federation of two regions populated by identical individuals, in which interregional migration is costly. We define a federation as an economy in which migration may not be restricted by governments. We compare and contrast firstbest efficiency (with migration controls) and federal efficiency (without migration controls). We show that firstbest efficiency requires maximising total product net of migration cost, while federal efficiency does not. We also show that migration costs may lead to a discontinuous federal utilitypossibility frontier and to discontinuous regional reaction functions. We establish that decentralised equilibrium allocations may not be firstbest efficient but are federally efficient. We conclude by tying together wellunderstood results from the limiting cases of free mobility and immobility with our results for the intermediate case.

M. R. Jepsen and S. Leisz and K. Rasmussen and J. Jakobsen and L. Mollerjensen and L. Christiansen

Shifting cultivation in the Nghe An Province of Vietnam’s Northern Mountain Region produces a characteristic land-cover pattern of small and larger fields. The pattern is the result of farmers cultivating either individually or in spatially clustered groups. Using spatially explicit agent-based modelling, and relying on empirical data from fieldwork and observations for parameterization of variables, the level of clustering in agricultural fields observed around a study village is reproduced. Agents in the model act to maximize labour productivity, which is based on potential yield and labour costs associated with fencing of fields, and are faced with physical constraints. The simulation results are compared with land-cover data obtained from remote sensing. Comparisons are made on patterns as detected visually and using the mean nearest-neighbour ratio. Baseline simulation outputs show high degrees of spatial clustering and similarity to the land-cover data, but also a need for further calibration of model variables and controls.

M. Wooders and E. Cartwright and R. Selten

In the literature of psychology and economics it is frequently observed that individuals tend to conform in their behavior to that of similar individuals. A fundamental question is whether the outcome of such conformity can be consistent with self-interest. We propose that this consistency requires the existence of a Nash or approximate Nash equilibrium that induces a partition of the player set into relatively few societies, each consisting of similar individuals playing similar strategies. In this paper we characterize a family of games admitting the existence of such equilibrium. We also introduce the concept of ‘crowding types’ into our description of players and distinguish between the crowding type of a player—those characteristics of a player that have direct effects on others—and his tastes. With assumptions of ‘within crowding type anonymity’ and ‘linearity of taste-types’ we show that the number of societies can be uniformly bounded.

J. Ely and D. Fudenberg and D. K. Levine

In traditional reputation models, the ability to build a reputation is good for the long-run player. In [Ely, J., Valimaki, J., 2003. Bad reputation. NAJ Econ. 4, 2; http://www.najecon.org/v4.htm. Quart. J. Econ. 118 (2003) 785–814], Ely and Valimaki give an example in which reputation is unambiguously bad. This paper characterizes a class of games in which that insight holds. The key to bad reputation is that participation is optional for the short-run players, and that every action of the long-run player that makes the short-run players want to participate has a chance of being interpreted as a signal that the long-run player is “bad.”We allow a broad set of commitment types, allowing many types, including the “Stackelberg type” used to prove positive results on reputation. Although reputation need not be bad if the probability of the Stackelberg type is too high, the relative probability of the Stackelberg type can be high when all commitment types are unlikely.

D. Krahmer, 06

The paper studies a repeated contest when contestants are uncertain about their true relative abilities. When ability and effort are complements, a favorable belief about one’s own ability stimulates effort and increases the likelihood of success. Success, in turn, reinforces favorable beliefs. We show that this implies that with positive probability players fail to learn their true relative abilities in equilibrium, and one player wins the contest with high probability forever. In this case, the prevailing player may be the actually worse player, and persistent inequality arises. We discuss some features of the model when the complementarity assumption is dropped.

J. Arifovic and R. D. McKelvey and S. Pevnitskaya

We report on a design of a Turing tournament and its initial implementation to learning in repeated 2- person games. The principal objectives of the tournament, named after the original Turing Test, are (1) to find learning algorithms (emulators) that most closely simulate human behavior, (2) to find algorithms (detectors) that most accurately distinguish between humans and machines, and (3) to provide a demonstration of how to implement this methodology for evaluating models of human behavior. In order to test our concept, we developed the software and implemented a number of learning models well known in the literature and developed a few detectors. This initial implementation found significant differences in data generated by these learning models and humans, with the greatest ones in coordination games. Finally, we investigate the stability of our result with respect to different evaluation approaches.

D. A. Bennett and W. Tang, 2006

The potential utility of agent-based models of adaptive, spatially aware, and mobile entities in geographic and ecological research is considerable. Developing this potential, however, presents significant challenges to geographic information science. Modelling the spatio-temporal behaviour of individuals requires new representational forms that capture how organisms store and use spatial information. New procedures must be developed that simulate how individuals produce bounded knowledge of geographical space through experiential learning, adapt this knowledge to continually changing environments, and apply it to spatial decision-making processes. In this paper, we present a framework for the representation of adaptive, spatially aware, and mobile agents. To provide context to this research, a multiagent model is constructed to simulate the migratory behaviour of elk (Cervus elaphus) on Yellowstone’s northern range. In this simulated environment, intelligent agents learn in ways that enable them to mimic real-world behaviours and adapt to changing landscapes.

I. Milchtaich, 2006

Different kinds of networks, such as transportation, communication, computer, and supply networks, are susceptible to similar kinds of inefficiencies. These arise when congestion externalities make the cost for each user depend on the other users’ choice of routes. If each user chooses the least expensive (e.g., the fastest) route from the users’ common point of origin to the common destination, the result may be Pareto inefficient in that an alternative choice of routes would reduce the costs for all users. Braess’s paradox represents an extreme kind of inefficiency, in which the equilibrium costs may be reduced by raising the cost curves. As this paper shows, this paradox occurs in an (undirected) two-terminal network if and only if it is not series-parallel. More generally, Pareto inefficient equilibria occur in a network if and only if one of three simple networks is embedded in it.

C.D. Aliprantis and G. Camera and D. Puzzellob

We develop theoretical underpinnings of pairwise random matching processes. We formalize the mechanics of matching, and study the links between properties of the different processes and trade frictions. A particular emphasis is placed on providing a mapping between matching technologies and informational constraints.

Games and Economic Behaviour

IJGIS special issue on spatial agent-based modelling 2006

Journal of Artificial Societies and Social Simulation

Riccardo Boero - The Spatial Dimension and Social Simulations: A Review of Three Books. Um texto interessante e uma boa revisao de tres livros tratando de sistemas de agentes e da importancia da dimensao espacial. The Spatial Dimension and Social Simulations

Caípitulo 2 do Russel sobre agentes.

Vale uma olhadela no site deste cara. E professor da USP Poli com interfaces com Portugal e Franca e no Brasil na area de Multi-agentes.

http://www.pcs.usp.br/~jaime/#projetos

with Suresh Naidu: Institutional Equilibrium Selection by Intentional Idiosyncratic Play, 2004

with Hebert Gintis: The inheritance of inequality, 2002