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Actores e Interacciones en el Uso de los Recursos Naturales en la Cuenca del Río Pichis, Selva Central del Perú
(2006) Pinedo, Danny
"Este estudio investiga cuáles son los diferentes actores y agentes en el uso de los recursos naturales y cómo ellos interactúan, así como cuál es el impacto de estas interacciones en el uso y manejo de los recursos pesqueros en la Amazonía peruana. Argumentamos que la idea convencional de la polarización entre extractores foráneos y población local no es el único rasgo que caracteriza las relaciones en la cuenca amazónica, sino que hay más bien una diversidad de actores que interactúan en un contexto dinámico. Los actores manifiestan diferentes estrategias que se traducen no sólo en relaciones conflictivas, sino también en diversas alianzas. Investigamos estos temas a través de un sondeo de varias poblaciones asentadas en las riberas del río Pichis y sus afluentes, en la selva central del Perú."
Adaptation and Sustainability in a Small Arctic Community: Results of an Agent-Based Simulation Model
(2004) Berman, Matthew; Nicolson, Craig; Kofinas, Gary P.; Tetlichi, Joe; Martin, Stephanie
"Climate warming and resource development could alter key Arctic ecosystem functions that support fish and wildlife resources harvested by local indigenous communities. A different set of global forces--government policies and tourism markets--increasingly directs local cash economies that communities use to support subsistence activities. Agent-based computational models (ABMs) contribute to an integrated assessment of community sustainability by simulating how people interact with each other and adapt to changing economic and environmental conditions. Relying on research and local knowledge to provide rules and parameters for individual and collective decision making, our ABM generates hypothetical social histories as adaptations to scenario-driven changes in environmental and economic conditions. The model generates projections for wage employment, cash income, subsistence harvests, and demographic change over four decades based on a set of user-defined scenarios for climate change, subsistence resources, development, and government spending. Model outcomes assess how scenarios associated with economic and climate change might affect the local economy, resource harvests, and the well-being of residents for the Western Arctic Canadian community of Old Crow, Yukon. The economic and demographic outcomes suggest implications for less quantifiable social and cultural changes. The model can serve as a discussion tool for a fuller exploration of community sustainability and adaptation issues."
Agent Mediated Consensus-Building for Environmental Problems: A Genetic Algorithm Approach
(1996) Bennett, David A.; Armstrong, Marc P.; Wade, Gred A.
"Environmental problems often result from the distributed and uncoordinated land use management practices of individual decision-makers that, when taken together, cause significant environmental impacts. To develop feasible and politically acceptable solutions to such problems it is often necessary to foster compromise and consensus among a diverse set of special interest groups who possess overlapping sets of objectives; some quantifiable, some not. The union of these sets forms a criteria space that constrains the set of feasible solutions that may be adopted by resource managers. As interest groups work toward the common goal of a mutually acceptable resource management plan they often require assistance in the development, representation, and analysis of this criteria space. Furthermore, new tools are needed that form explicit links between criteria space and the geographic space that is being managed. This paper illustrates how genetic algorithms are used to construct a link between criteria and geographic space and to evolve mutually acceptable solutions to complex environmental problems. Intelligent agents help decision-makers invoke various criteria and learn from the successes and failures of generated solutions in both geographic and criteria space. This knowledge is used to help users assess the fitness of alternative solutions and generate improved solutions to complex environmental problems."
Agent-based Analysis of Agricultural Policies: an Illustration of the Agricultural Policy Simulator AgriPoliS, its Adaptation and Behavior
(2006) Happe, Kathrin; Kellerman, Konrad; Balmann, Alfons
"This paper combines agent-based modeling of structural change with agricultural policy analysis. Using the agent-based model AgriPoliS, we investigate the impact of a regime switch in agricultural policy on structural change under various framework conditions. Instead of first doing a sensitivity analysis to analyze the properties of our model and then examining the introduced policy in an isolated manner, we use a meta-modeling approach in combination with the statistical technique of Design of Experiments to systematically analyze the relationship between policy change and model assumptions regarding key determinants of structural change such as interest rates, managerial abilities, and technical change. As a result, we observe that the effects of policies are quite sensitive to the mentioned properties. We conclude that an isolated analysis of a policy regime switch would be of only minor value for policy advice given the ability of simulation models to examine various potential futures."
Agent-Based Modeling as a Tool for Policy Making Towards Common-Pool Resources: Palm Heart Harvesting and Traditional Communities in Brazil
(2013) de Andrade Lima, Raoni Venturieri; Adams, Cristina; Raimbert, Céline; Fagundes Ferreira, Fernando
"Public environmental policies aiming at protecting endangered and shared natural resources are frequently imposed by governments on indigenous people. Based on traditional economic theory, they usually forbid the appropriation of resources from the natural environment. In the Brazilian Atlantic Forest, one of the world's biodiversity hotspots, the prohibition imposed on the extraction of palm tree Euterpe edulis Mart. has resulted in a decrease in indigenous people's household income and has not effectively preserved this keystone species, which is close to extinction in many areas. This scenario offers an opportunity to use computational simulations to test different institutional scenarios that could help tackling social and ecological issues simultaneously. By examining varied rules and anticipating outcomes before decisions are taken, computational models can help to optimize policy interventions. In this paper we will show the outcome of two agent based models that aim at comparing the performance of two distinct policy scenarios to control palm heart harvesting. One represents the current situation and is based on central control by the government. Community members that violate the rules are subject to punishment and can be fined. The second model is decentralized and based on community control. The community sets out the rules and is responsible for supervising its members. In this model, a rule is proposed to reward or to punish the agents according to their actions (cooperate or defect). By varying the parameters, we tested if the decentralized model is more efficient to secure a sustainable harvesting of E. edulis from the forest. It will be shown how simulations can help to design and select public policies that both empower local communities and preserve endangered species."
Agents, Individuals, and Networks: Modeling Methods to Inform Natural Resource Management in Regional Landscapes
(2012) Parrott, Lael; Chion, Clément; Gonzaléz, Rodolphe; Latombe, Guillaume
"Landscapes are complex systems. Landscape dynamics are the result of multiple interacting biophysical and socioeconomic processes that are linked across a broad range of spatial, temporal, and organizational scales. Understanding and describing landscape dynamics poses enormous challenges and demands the use of new multiscale approaches to modeling. In this synthesis article, we present three regional systems--i.e., a forest system, a marine system, and an agricultural system--and describe how hybrid, bottom-up modeling of these systems can be used to represent linkages across scales and between subsystems. Through the use of these three examples, we describe how modeling can be used to simulate emergent system responses to different conservation policy and management scenarios from the bottom up, thereby increasing our understanding of important drivers and feedback loops within a landscape. The first case study involves the use of an individual-based modeling approach to simulate the effects of forest harvesting on the movement patterns of large mammals in Canada's boreal forest and the resulting emergent population dynamics. This model is being used to inform forest harvesting and management guidelines. The second case study combines individual and agent-based approaches to simulate the dynamics of individual boats and whales in a marine park. This model is being used to inform decision-makers on how to mitigate the impacts of maritime traffic on whales in the Saint Lawrence Estuary in eastern Canada. The third example is a case study of biodiversity conservation efforts on the Eyre Peninsula, South Australia. In this example, the social-ecological system is represented as a complex network of interacting components. Methods of network analysis can be used to explore the emergent responses of the system to changes in the network structure or configuration, thus informing managers about the resilience of the system. These three examples illustrate how bottom-up modeling approaches may contribute to a new landscape science based on scenario building, to find solutions that meet the multiple objectives of integrated resource management in social-ecological systems."
Co-Evolution of Norms and Cooperation
(2014) Jiménez Tovar, Fernando; Lara Rivero, Arturo A.
"Cooperation is profitable from an evolutionary point of view as long as individuals have the right combination of cognitive and emotional faculties that enable them to extract the beliefs and values that are hidden on the behavior of other individuals. The ability of imitating intentions and not only actions has informational and regulatory reasons in social life that can generate cooperative equilibriums. Using simulation models it is possible to study how the process of institutional evolution affects the evolution of cooperation in a group of agents involved in a social dilemma situation. ADICO grammar proposed by Elinor Ostrom (2005) allows us to accurately classify and study the process of institutional evolution between different types of institutional statements. In this paper we use a cellular automata as an idealized version of a complex adaptive system and discuss how a shared strategy (AIC) can evolve to become a norm (ADIC) and what is the impact of this process on the evolution of cooperation in the system. It can be shown that this process of institutional evolution can promote a great diversity of norms from a single shared strategy. It is observed that the process of co-evolution of norms and cooperation produces better outcomes for populations of individuals who develop internal and external delta values compared to cases where no institutional evolution is achieved."
Coordination in Irrigation Systems: An Analysis of the Lansing-Kremer Model of Bali
(2007) Janssen, Marco A.
"Farmers within irrigation systems, such as those in Bali, solve complex coordination problems to allocate water and control pests. Lansing and Kremer's [Lansing, J.S., Kremer, J.N., 1993. Emergent properties of Balinese water temples. American Anthropologist 95(1), 97-114] study of Balinese water temples showed that this coordination problem can be solved by assuming simple local rules for how individual communities make their decisions. Using the original Lansing-Kremer model, the robustness of their insights was analyzed and the ability of agents to self-organize was found to be sensitive to pest dynamics and assumptions of agent decision making."
Cost Allocation and Airport Problems
(2007) Thomson, William
"We consider the problem of dividing the cost of a facility when agents can be ordered in terms of the need they have for it, and accommodating an agent with a certain need allows accommodating all agents with lower needs at no extra cost. This problem is known as the 'airport problem,' the facility being the runway. We review the literature devoted to its study, and formulate a number of open questions."
Developing a Spatially Explicit Agent-Based Model of Queen Conch Distribution in a Marine Protected Area in the Turks and Caicos Islands
(2001) Rudd, Murray A.; Railsback, Steve; Danylchuk, Andy; Clerveaux, Wesley
"Queen conch, Strombus gigas, is an important commercial resource in the Turks and Caicos Islands (TCI). The TCI government is funding the development of an agent-based model (ABM) to help better understand queen conch distribution and manage the artisanal fishery. ABMs are built from the ?bottom up? and simulate each individual agent ? conch, fishers and the fishery manager ? within the pertinent system. Agents follow relatively simple rules of behavior at the individual level but can engage in behavior that leads to complicated aggregate patterns of interaction. ABMs permit modelers to perform a variety of resource management experiments in a computer-generated artificial fisheries management laboratory, potentially increasing our ability to implement the principle of adaptive management while reducing the risk and/or time lags of real-world experiments. The purpose of this paper is to outline the development of the spatial components of a pilot model in which simple foragers (conch) live, grow and disperse. The model of the South Caicos East Harbor Lobster and Conch Reserve (EHLCR) uses habitat data derived from Landsat 7 satellite imagery as an environmental base and is implemented using the Swarm modeling platform. In the model, conch survival is dependent on (1) food intake and (2) mortality risk within each habitat type. The challenges of expanding the model from this pilot phase to incorporate more sophisticated fisher and fishery management agents in an expanded commercial fishery model are outlined."
Empirically Based, Agent-based Models
(2006) Janssen, Marco A.; Ostrom, Elinor
"There is an increasing drive to combine agent-based models with empirical methods. An overview is provided of the various empirical methods that are used for different kinds of questions. Four categories of empirical approaches are identified in which agent-based models have been empirically tested: case studies, stylized facts, role-playing games, and laboratory experiments. We discuss how these different types of empirical studies can be combined. The various ways empirical techniques are used illustrate the main challenges of contemporary social sciences: (1) how to develop models that are generalizable and still applicable in specific cases, and (2) how to scale up the processes of interactions of a few agents to interactions among many agents."
Encouraging Sustainable Transport Choices in American Households: Results from an Empirically Grounded Agent-Based Model
(2014) Natalini, Davide; Bravo, Giangiacomo
"The transport sector needs to go through an extended process of decarbonisation to counter the threat of climate change. Unfortunately, the International Energy Agency forecasts an enormous growth in the number of cars and greenhouse gas emissions by 2050. Two issues can thus be identified: (1) the need for a new methodology that could evaluate the policy performances ex-ante and (2) the need for more effective policies. To help address these issues, we developed an Agent-Based Model called Mobility USA aimed at: (1) testing whether this could be an effective approach in analysing ex-ante policy implementation in the transport sector; and (2) evaluating the effects of alternative policy scenarios on commuting behaviours in the USA. Particularly, we tested the effects of two sets of policies, namely market-based and preference-change ones. The model results suggest that this type of agent-based approach will provide a useful tool for testing policy interventions and their effectiveness."
Environmental Licensing and Land Aggregation: An Agent-Based Approach to Understanding Ranching and Land Use in Rural Rondônia
(2011) Bell, Andrew Reid
"Agricultural development and climate change will be two of the major stressors on the Amazon natural-human system in the decades to come. Environmental licensing for rural properties is being implemented in several states in the Brazilian Amazon with the goal of restoring forests in agricultural landscapes and mediating the impacts of these stressors. This study presents an agent-based model of ranching and land exchange, informs it with empirical results from social research in the Ji-Paraná River Basin, Rondônia, Brazil, and investigates the social, economic, and environmental outcomes that can be expected as a result of environmental licensing in the context of climate change. Model results informed by these data suggest that although an environmental licensing scheme with monitoring and enforcement may increase the level of forested land in ranching landscapes, it may do so at the expense of the small producer. To the extent that effective monitoring and enforcement exist, a focus on larger holdings will help to mediate this negative social impact. These results suggest that a middle ground can be found in cases where current environmental goals conflict with legacies of past colonization and resource-use regimes."
Examining Fire-Prone Forest Landscapes as Coupled Human and Natural Systems
(2014) Spies, Thomas A.; White, Eric M.; Kline, Jeffret D.; Fischer, Paige A.; Ager, Alan; Bailey, John; Bolte, John; Koch, Jennifer; Platt, Emily; Olsen, Christine S.; Jacobs, Derric; Shindler, Bruce; Steen-Adams, Michelle M.; Hammer, Roger
"Fire-prone landscapes are not well studied as coupled human and natural systems (CHANS) and present many challenges for understanding and promoting adaptive behaviors and institutions. Here, we explore how heterogeneity, feedbacks, and external drivers in this type of natural hazard system can lead to complexity and can limit the development of more adaptive approaches to policy and management. Institutions and social networks can counter these limitations and promote adaptation. We also develop a conceptual model that includes a robust characterization of social subsystems for a fire-prone landscape in Oregon and describe how we are building an agent-based model to promote understanding of this social-ecological system. Our agent-based model, which incorporates existing ecological models of vegetation and fire and is based on empirical studies of landowner decision-making, will be used to explore alternative management and fire scenarios with land managers and various public entities. We expect that the development of CHANS frameworks and the application of a simulation model in a collaborative setting will facilitate the development of more effective policies and practices for fire-prone landscapes."
Exploring Heterogeneity in Common Pool Resource Experiments with Intelligent Agent Based Simulations
(1998) Deadman, Peter J.
Author's Abstract: "This work utilizes previously documented common pool resource experiments as a foundation for the construction of a series of computer simulations in which the individuals participating in the experiments are represented as separate intelligent agents. An intelligent agent is an autonomous, self-contained entity that resides within a virtual, computer-based, environment. In this study, agents are created to represent the individual participants in the CPR experiment and the resource that they share in common. By programming the agents with different strategies and endowments, the researcher can allow the agents to interact within a prespecified environment and observe the outcomes. These outcomes may include the performance of individual strategies in a specific environment, or the overall behavior of the group that emerges as a result of the numerous interactions of the individual agents. These models allow the researcher to observe the relative performance, at the individual and group level, of different combinations of individual strategies and to begin to draw connections between individual behaviors and group outcomes. "Group performance in heterogeneous simulations can vary significantly with minor changes in the initial parameters of the environment or the characteristics of the agents. Simulations which allow for simplified communication between agents show that a lock-in can occur in which the agents agree on a group wide investment strategy which may or may not be an optimal solution. Some general discussion of the results of these simulations is provided, including a comparison with some observations from experimental economics and game theory. Preliminary observations on the advantages and disadvantages of agent based simulation as a tool for the analysis of the commons dilemma and issues related to heterogeneity are provided, along with some suggestions for future directions in which this work might proceed."
Governing Social-Ecological Systems
(Elsevier, 2006) Janssen, Marco A.; Ostrom, Elinor; Tesfatsion, L.; Judd, K.L.
"Social-ecological systems are complex adaptive systems where social and biophysical agents are interacting at multiple temporal and spatial scales. The main challenge for the study of governance of social-ecological systems is improving our understanding of the conditions under which cooperative solutions are sustained, how social actors can make robust decisions in the face of uncertainty and how the topology of interactions between social and biophysical actors affect governance. We review the contributions of agent-based modeling to these challenges for theoretical studies, studies which combines models with laboratory experiments and applications of practical case studies. "Empirical studies from laboratory experiments and field work have challenged the predictions of the conventional model of the selfish rational agent for common pool resources and public-good games. Agent-based models have been used to test alternative models of decision-making which are more in line with the empirical record. Those models include bounded rationality, other regarding preferences and heterogeneity among the attributes of agents. Uncertainty and incomplete knowledge are directly related to the study of governance of social-ecological systems. Agent-based models have been developed to explore the consequences of incomplete knowledge and to identify adaptive responses that limited the undesirable consequences of uncertainties. Finally, the studies on the topology of agent interactions mainly focus on land use change, in which models of decision-making are combined with geographical information systems. "Conventional approaches in environmental economics do not explicitly include nonconvex dynamics of ecosystems, non-random interactions of agents, incomplete understanding, and empirically based models of behavior in collective action. Although agent-based modeling for social-ecological systems is in its infancy, it addresses the above features explicitly and is therefore potentially useful to address the current challenges in the study of governance of social-ecological systems."
Harnessing the Climate Commons: An Agent-based Modelling Approach to Reduce Carbon Emission from Deforestation and Degradation
(2011) Purnomo, Herry; Suyamto, Desi; Akiefnawati, Ratna; Abdullah, Lutfy; Irawati, Rika Harini
"Humans have created a worldwide tragedy through free access to the global common atmosphere. Forest land use change contributes 18% of greenhouse gas emissions, which cause global warming. The 15th Conference of the Parties in Copenhagen increased political commitment to reduce emission from deforestation and degradation and to enhance carbon stocks (REDD+). However, government sectors, political actors, business groups, civil societies, tree growers and other interest groups at different levels may support or reject REDD+. This paper describes REDD+ dynamics through the following methods: identifying key actors that influence REDD+ policy; categorizing their objectives and interests, types of rationality and policy preferences; pointing out the strategies they used to fulfill their goals and simulating their actions and behaviors with an agent-based modelling approach. Through analysis of actors, arenas and institutions, various possible REDD+ options are explored. The model simulates: (1) how providers are likely to decrease or increase carbon stocks on their landscapes for their livelihoods under ‘business as usual’ institutions; (2) how they are likely to negotiate with potential buyers to implement REDD+, with regards to the involvement of brokers (governments or nongovernmental organizations); and (3) how they are likely to implement REDD+ after the agreement. The model has been/was developed as a spatially explicit model to consider the complexity of REDD+ target landscapes. The simulation results are examined against the 3E+ criteria, i.e. effectiveness in carbon emission reduction, cost efficiency and equity among involved stakeholders and co-benefit of other activities. This study took the Jambi landscape in Indonesia as a case/case study. The results explain why REDD+ works and does not work, who wins and loses, and develops scenarios for REDD+ institutional arrangements which would help to harness the global commons of climate change."
Mobility, Resource Harvesting and Robustness of Social-Ecological Systems
(2012) Ibarra, Irene Perez; Janssen, Marco A.
"Globalization is an important feature aecting the robustness of small-scale social-ecological systems (SESs). Understanding the way globalization aects those systems is crucial for adaptation. In this paper we focus on analyzing how the increased displacement of resource users as a consequence of globalization aects the robustness of SESs. We developed a stylized agent-based model representing a dynamic population of agents moving and harvesting a renewable resource. The individual characteristics and behavior of agents and governments determine the robustness or collapse of the system. We analyzed several scenarios in which we vary the mobility of the agents (i.e., the extent to which agents can move), the distribution of the resource richness and the amount of information governments have regarding potential intruders. Our results showed that agent mobility signicantly affects the robustness of the SES. This response is non linear and very sensible to the type of spatial distribution of the resource richness. The attractiveness of rich resource sites (local level) to agents makes them vulnerable to rapid collapse with consequences to the global system. While medium heterogeneous landscapes are very robust to mobility, highly heterogeneous landscapes (i.e., exponential distribution of resource richness) are not able to absorb such a disturbance; the system stability as well as the resource and occupation levels drop as mobility increases. An increase in enforcement is not sucient for the robustness of such SESs. Results suggest the importance of global governance to deal with governance of resource rich areas, not only for local governments because those areas are more prone to invasions but for global sustainability itself."
Modelling Evolving Rules for the Use of Common-Pool Resources in an Agent-Based Model
(2007) Smajgl, Alexander
"Institutional arrangements are key drivers of the use of common-pool resources (CPR). The analysis of existing arrangements requires a framework that allows research to describe a case study systematically and diagnose the institutional setting. Based on a sound understanding of current institutions the question of what effects alternate arrangements would have becomes evident. This step requires a predictive model, which can either be qualitative or, preferably, analyses an empirical case quantitatively. A major conceptual challenge of a quantitative model is the evolution of rules, which define the boundaries for the agents to choose strategies. This paper develops the conceptual foundations for such a modelling approach and an agent-based model for the analysis of institutional arrangements in a CPR setting."
Modelling Evolving Rules for the Use of Common-Pool Resources in an Agent-Based Model
(2004) Smajgl, Alexander
"Institutional arrangements are key drivers of the use of common-pool resources (CPR). The analysis of existing arrangements requires a framework that allows research to describe a case study systematically and diagnose the institutional setting. Based on a sound understanding of current institutions the question of what effects alternate arrangements would have becomes evident. This step requires a predictive model, which can either be qualitative or, preferably, analyses an empirical case quantitatively. A major conceptual challenge of a quantitative model is the evolution of rules, which define the boundaries for the agents to choose strategies. This paper develops the conceptual foundations for such a modeling approach and an agent-based model for the analysis of institutional arrangements in a CPR setting."
Multi-Agent Systems (MAS) Modelling to Improve the Management of Common: Renewable Resources in Palawan, Philippines
(2006) Campo, Paulo; Villanueva, T.R.
"This paper reports experiences and inferences of an on- going study on the use of contemporary analytical tool, Multi-agent system (MAS) to study the dynamics and complex interactions among stakeholders in the management of common renewable resources. The study is being conducted as one of the components of the Levelling the Playing Field Project in Palawan, Philippines and is being implemented in the villages of San Rafael, Tanabag, and Concepcion, Puerto Princesa City in Palawan, Philippines. Here, the management of renewable resources is characterized by participation of many stakeholders who have different and competing interests, objectives and motives. The community groups and government and nongovernment organizations also have different positions of power that makes collaborative management difficult. Conflicting laws and environmental policies often lead to confusion and conflicts among the stakeholders. New management policies imposing new access rule to resources also threatens the livelihood of the community."
Population Aggregation in Ancient Arid Environments
(2010) Janssen, Marco A.
"Human societies have adapted to spatial and temporal variability, such as that found in the prehistoric American Southwest. A question remains as to what the implications are of different social adaptations to long-term vulnerability of small-scale human societies. A stylized agent-based model is presented that captures small-group decision making on movements and resource use in ancient arid environments. The impact of various assumptions concerning storage, exchange, sharing, and migration on indicators of aggregation and sustainability are explored. Climate variability is found to increase the resilience of population levels at the system level. Variability reduces the time a population stays in one location and can degrade the soils. In addition to climate variability, the long-term population dynamics is mainly driven by the level of storage and the decision rules governing when to migrate and with whom to exchange."
Risk, Networks, and Ecological Explanations for the Emergence of Cooperation in Commons Governance
(2012) Henry, Adam Douglas; Vollan, Björn
"The commons literature increasingly recognizes the importance of contextual factors in driving collaboration in governance systems. Of particular interest are the ways in which the attributes of a resource system influence the dynamics of cooperation. While this may occur through many pathways, we investigate the mechanisms by which ecological factors influence both the risk of cooperation as well as the density of networks in which strategic interactions take place. Both of these factors influence the co-evolutionary dynamics of network structure and cooperative behavior. These dynamics are investigated through agent-based simulations, which provide preliminary evidence that: 1) low-density networks support higher levels of cooperation, even in high-risk Prisoners Dilemma scenarios; and 2) in high-risk scenarios, networks that develop higher levels of clustering generally enjoy higher societal gains."
Simulating Institutional Dynamics in the Context of Water in Outback Australia
(2006) Smajgl, Alexander; Heckbert, Scott
"Water availability in outback Australia is event driven and flips often from a situation of scarcity to a temporary abundance. Informal institutions are often able to translate such dynamics in sustainable user rules. Policy interventions are mainly focused on changing access rules to avoid over use or inefficiencies. Ripple effects of such formal institutional changes can lead to unexpected unsustainable outcomes; outcomes that are often captured in the 'story' behind informal arrangements. This paper analyses one case study on water access in outback Australia and translates field work results into an agent based model. In order to project ripple effects of institutional changes interventions in water access is assumed in an applied context. Core focus of the modelling exercise is the treatment of newcomers on a newly created trading scheme for water access rights. Simulations compare different options and how perceived risk of existing irrigators might change."
Spatial Complexity, Resilience, and Policy Diversity: Fishing on Lake-Rich Landscapes
(2004) Carpenter, Stephen; Brock, William A.
"The dynamics of and policies governing spatially coupled social-ecological mosaics are considered for the case of fisheries in a lake district. A microeconomic model of households addresses agent decisions at three hierarchic levels: (1) selection of the lake district from among a larger set of alternative places to live or visit, (2) selection of a base location within the lake district, and (3) selection of a portfolio of ecosystem services to use. Ecosystem services are represented by dynamics of fish production subject to multiple stable domains and trophic cascades. Policy calculations show that optimal policies will be highly heterogeneous in space and fluid in time. The diversity of possible outcomes is illustrated by simulations for a hypothetical lake district based loosely on the Northern Highlands of the State of Wisconsin. Lake districts are frequently managed as if lakes were independent, similar, endogenously regulating systems. Our findings contradict that view. One-size-fits-all (OSFA) policies erode ecological and social resilience. If regulations are too stringent, social resilience declines because of the potential rewards of overharvesting. If regulations are too lax, ecological resilience is diminished by overharvesting in some lakes. In either case, local collapses of fish populations evoke spatial shifts of angling effort that can lead to serial collapses in neighboring fisheries and degraded fisheries in most or all of the lakes. Under OSFA management, the natural resources of the entire landscape become more vulnerable to transformation because of changes in, e.g., human population, the demand for resources, or fish harvesting technology. Multiplicity of management regimes can increase the ecological resilience, social resilience, and inclusive value of a spatially heterogeneous social-ecological system. Because of the complex interactions of mobile people and multistable ecosystems, management regimes must also be flexible over time. A rights-based scheme may facilitate policy regimes with appropriate spatial patterns and intertemporal fluidity. In lake fisheries, habitat protection adds an important dimension to policy design. Habitat is a slowly changing variable that creates ecological resilience and thereby provides managers with a broader range of options."
The Tragedy of the Park: An Agent-based Model of Endogenous and Exogenous Institutions for Forest Management
(2014) Vallino, Elena
"Many scholars of common-pool resources have found that institutions might solve the tragedy of the commons. I address a particular situation of natural resource management: that of a protected area. In this situation, interests differ. Local rural inhabitants care about the quality of their environment but also need to exploit the resources for livelihood reasons. An external entity such as the State, a donor, an NGO, or some combination thereof decides that there is a need for nature conservation in that area. Because of some evidence of failure for a strictly top-down conservationist approach, the external entity decides to apply the concept of participatory conservation: the local inhabitants become stakeholders in the management of the area and become collectively responsible for conservation, with rights to exploit the resources up to some degree. I argue that project designers try to find a solution to nature conservation through the creation of a situation of a commons: creating a community that has rights and duties toward a particular natural area that is endowed with some resources. Many scholars rely mostly on institutions that are endogenously created within the users’ community to avoid the tragedy of the commons. However, what happens if institutions are imposed? In participatory conservation initiatives, the community has collective rights over the resources, and in this sense, the issue of endogenous rules for the commons management is relevant. However, the level to which the community should exploit the resource is usually imposed by the external project designers. Using agent-based simulations, I develop a theoretical model to look at the consequences of an imposed institution on the state of a forest and on the users’ profit, taking into account the possibilities of violating the imposed rules and facing enforcement. I compare the consequences of this imposed institution with those deriving from an endogenously created institution. I also analyze the interaction between the different kinds of institutions and the individual perceptions of each agent. Many results of the model confirm the quantitative and qualitative findings of the literature: the presence of institutions and enforcement improve the management of the resource with respect to an open-access situation, with different degree of success depending on the kind of institution in place. The two main counterintuitive findings are the following. First, an exogenous institution imposed by external agents may crowd out agents’ intrinsic environmental motivations. Second, when an imposed exogenous institution is in place, the most effective rule is one allowing a sufficient degree of access to resources for the agents, provided that adequate rule enforcement is implemented."
Understanding the Free/Libre Open Source Software (FLOSS) Development Process: An Agent-Based Model
(2010) Radtke, N.P.; Janssen, Marco A.; Collofello, J.S.
"Free/Libre Open Source Software (FLOSS) is the product of volunteers collaborating to build software in the public domain. The large number of FLOSS projects, combined with the data that is inherently archived with this online process, make studying this phenomenon attractive. Some FLOSS projects are very functional, well-known, and successful, such as Linux, the Apache web server, and Firefox. However, for every successful FLOSS project there may be 100’s of projects that are unsuccessful. These projects fail to attract sufficient interest from developers and users and become inactive or abandoned before useful functionality is achieved. The goal of this research is to better understand the open source development process and gain insight into why some FLOSS projects succeed while others fail. This paper presents a simple agent-based model of the FLOSS development process. In the model agents, as either developers or users, select from a landscape of FLOSS projects to be involved in. Via the selections that are made, and subsequent contributions, some projects are propelled to success while others are stagnant and inactive. The model is able to reproduce key characteristics observed in empirical FLOSS data and offers insight into how developers select FLOSS projects, ultimately causing certain projects to flourish while others are abandoned."
Unravelling Institutional Complexity: Actors and Rules Negotiating Water in Indian Himalayas
(2006) Saravanan, V. S.; McDonald, Geoff; Van Horen, Basil; David, I. P.; Saleth, Rathinasamy Maria
"Institutions integrate in a complex manner across levels in shaping and reshaping water resource management. Unraveling the complex interaction among institutions requires identifying the role of actors and rules in managing water resource. New institutionalisms across social sciences are critically evaluated for a framework to analyse interactions and the relationship between land, water and societies. The paper aims to analyse the interactive nature of actors and rules: (i) influencing water policy and administration; (ii) building capability of actors to manage water crisis; and (iii) building capability of agents to negotiate towards seeking alternatives for a desired change. These objectives are examined to a core water-related issue applicable in each of the four socio-economically and hydrologically distinct hamlets selected from two watersheds in Himachal Pradesh, India. Different research investigations (primary, lead, follow-up and check) were carried by combining different research methods. "The study adopts a systematic approach to identify actors and rules integrating at various arenas to manage water. These arenas representing adaptive cycle of resource management are obscure, not clearly represented, but are hierarchically interlinked forming a 'Panarchy'. The study evaluates institutions in these arenas in four phases of adaptive cycle: policy formulation, implementation, attempts to overcome water crisis; and ability of agents to seek institutional alternatives. This helps in identifying rules that can enable actors to consciously design and self- organise towards integrating water management. The study reveals diverse actors in shaping water policies, but the absence of scope and information rules constrains these actors in taking informed decisions for a sustainable future. Implementation of these policies is controlled by statutory public actors who provide boundary rules for other actors in the watershed well endowed with infrastructure facilities, while it is socially embedded actors in remote watershed. However, it is statutory public actors who provide authority rules thereby knowingly or unknowingly facilitating inequitable distribution of water. Socially embedded actors provide all the rules required for actors to build their capability to manage water. Each of these actions is facilitated by agents who are located at various levels in space and time to integrate various actors and rules to institute change. In brief the study highlights the importance of infrastructure development for poverty alleviation, information sharing and importance of sectoral agencies to remain interactive. The findings question some of the contemporary understanding of decentralisation, resilience, collective action and participatory management providing new theoretical grounds for analysing water resource institutions."
Using Coupled Simulation Models to Link Pastoral Decision Making and Ecosystem Services
(2011) Boone, Randall B.; Galvin, Kathleen A.; BurnSilver, Shauna B.; Thornton, Philip; Oijma, Dennis S.; Jawson, Jacob R.
"Historically, pastoral people were able to more freely use the services their semi-arid and arid ecosystems provide, and they adapted to changes in ways that improved their well-being. More recently, their ability to adapt has been constrained due to changes from within and from outside their communities. To compare possible responses by pastoral communities, we modeled ecosystem services and tied those services to decisions that people make at the household level. We created an agent-based household model called DECUMA, joined that model with the ecosystem model SAVANNA, and applied the linked models to southeastern Kajiado District, Kenya. The structure of the new agent-based model and linkages between the models are described, and then we demonstrate the model results using a scenario that shows changes in Maasai well-being in response to drought. We then explore two additional but related scenarios, quantifying household well-being if access to a grazing reserve is lost and if access is lost but those most affected are compensated. In the second scenario, households in group ranches abutting the grazing reserve that lost access had large declines in livestock populations, less food energy from animal sources, increased livestock sales and grain purchases, and increased need for supplemental foods. Households in more distant areas showed no changes or had increases in livestock populations because their herds had fewer animals with which to compete for forage. When households neighboring the grazing reserve were compensated for the lease of the lands they had used, they prospered. We describe some benefits and limitations of the agent-based approach."
What to Monitor and at which Scale: Fragmented Landscapes and Insights on Large-Scale Conservation Management
(2013) Schoon, Michael L.; Baggio, Jacopo A.; Salau, Kehinde R.; Janssen, Marco A.
"In recent years there has been a shift in biodiversity conservation eorts from the connes of enclosed protected areas to a more expansive view of interlinked habitat patches across multiple land tenure types and land uses. However, much work remains on how conservation managers can intervene in such a system to achieve the sustainability of basic conservation goals. An agent-based model of a two-patch metapopulation with local predator-prey dynamics and variable, density-dependent species migration is used to examine the capacity of a manager to interact with and modify the ecosystem to achieve biodiversity conservation goals. We explore managers strategies aimed at main-taining one of two goals local coexistence of both predators and prey (sustained coexistence on one patch) or global coexistence of predators and prey (sustained coexistence on both patches). To achieve managements goal, the manager varies the level of connectivity between two habitat patches (i.e. a manager is thus able to facilitate or restrict movement of species between habitat patches) based on one of three monitoring strate-gies the monitoring of predator population levels, the monitoring of prey population levels, or the monitoring of the vegetation carrying capacity of the habitat patches. Our goal is to help facilitate management decisions and monitoring choices in conservation projects that move beyond the confines of a protected area and into mosaics of multiple land tenure types typical of many of todays large-scale conservation projects."

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