abstract: This dissertation investigates the dynamics of evolutionary games based on the framework of interacting particle systems in which individuals are discrete, space is explicit, and dynamics are stochastic. Its focus is on 2-strategy games played on a d-dimensional integer lattice with a range of interaction M. An overview of related past work is given along with a summary of the dynamics in the mean-field model, which is described by the replicator equation. Then the dynamics of the interacting particle system is considered, first when individuals are updated according to the best-response update process and then the death-birth update process. Several interesting results are derived, and the differences between the interacting particle system model and the replicator dynamics are emphasized. The terms selfish and altruistic are defined according to a certain ordering of payoff parameters. In these terms, the replicator dynamics are simple: coexistence occurs if both strategies are altruistic; the selfish strategy wins if one strategy is selfish and the other is altruistic; and there is bistability if both strategies are selfish. Under the best-response update process, it is shown that there is no bistability region. Instead, in the presence of at least one selfish strategy, the most selfish strategy wins, while there is still coexistence if both strategies are altruistic. Under the death-birth update process, it is shown that regardless of the range of interactions and the dimension, regions of coexistence and bistability are both reduced. Additionally, coexistence occurs in some parameter region for large enough interaction ranges. Finally, in contrast with the replicator equation and the best-response update process, cooperators can win in the prisoner's dilemma for the death-birth process in one-dimensional nearest-neighbor interactions. / Dissertation/Thesis / Doctoral Dissertation Applied Mathematics 2016

Studies of life span development in everyday problem solving suggest two trajectories of change in adulthood: individuals become less effective at solving well-defined instrumental problems but more effective at managing ill-defined interpersonal problems. Two experiments were conducted to examine the ability of young and older adults to effectively manage an interpersonal problem that has a well-defined measure of instrumental success. Participants played an iterated Prisoner s Dilemma game with same-age, computer-simulated strangers (Experiment 1) and friends (Experiment 2). Success was dependent upon one s ability to put aside self-interest and cooperate with a partner. Computer-simulated partners reciprocated the participants decisions 100% of the time or behaved in a more self-interested manner. Young and older adults tendencies to create conflict with the reciprocating partner and their defensive reactions to the selfish partner were examined. Although young adults outperformed older adults when playing the game on their own, they did not carry this performance advantage into the interactive rounds. In fact, despite their success when playing alone, young adults were no more successful than older adults when interacting with others. Young and older adults both cooperated more with friends than with strangers and more with the reciprocating partner than the selfish partner. However, when the participants first interaction was with a selfish stranger, older adults were more cooperative than young adults and consequently accrued more reward. This is consistent with previous research demonstrating that older adults use more passive interpersonal problem solving strategies than young adults, and it also partially supports the prediction that advancing age leads to more effective strategy implementation when solving interpersonal problems.

Theory as an approach to generative composition and interactive computer music. Inspired by the notion of Performance Indeterminacy, software has been developed that attempts to simulate the interactions of improvising performers using a multi-agent system based on the ‘Iterated Prisoner’s Dilemma’. Composition activities and programming activities have formed a symbiotic relationship throughout the creation of the portfolio as each has constantly informed the other. Stylistically, the works presented fall into the experimental genre, although individually they address a wide range of aesthetic goals. The main contribution of this portfolio is a new approach to generative composition based on behavioural models, creating a sense of form bottom-up through modelling the social dynamics of music performance. Through this approach, the direct modelling of musical structures is avoided; instead larger scale forms emerge through the interactions of an ensemble of ‘improvising’ agents. This method offers a departure from previous complex systems work in the area of music, creating computer models of specific musical situations. Links between the Iterated Prisoner’s Dilemma and music are also established and combined with current music technologies. / Thesis(Ph.D.)- University of Adelaide, Elder Conservatorium of Music, 2008

Theory as an approach to generative composition and interactive computer music. Inspired by the notion of Performance Indeterminacy, software has been developed that attempts to simulate the interactions of improvising performers using a multi-agent system based on the ‘Iterated Prisoner’s Dilemma’. Composition activities and programming activities have formed a symbiotic relationship throughout the creation of the portfolio as each has constantly informed the other. Stylistically, the works presented fall into the experimental genre, although individually they address a wide range of aesthetic goals. The main contribution of this portfolio is a new approach to generative composition based on behavioural models, creating a sense of form bottom-up through modelling the social dynamics of music performance. Through this approach, the direct modelling of musical structures is avoided; instead larger scale forms emerge through the interactions of an ensemble of ‘improvising’ agents. This method offers a departure from previous complex systems work in the area of music, creating computer models of specific musical situations. Links between the Iterated Prisoner’s Dilemma and music are also established and combined with current music technologies. / Thesis(Ph.D.)- University of Adelaide, Elder Conservatorium of Music, 2008

The Internet has made a considerable impact on how business is conducted. Empowered by technology consumers are using the Internet as a tool to communicate and transact online. E-commerce (electronic commerce) presents opportunities for business to gain a competitive advantage, however it also posses certain challenges. Small and Medium Hospitality Enterprises (SMHEs) sector within the tourism industry, is one of the sectors which stands to benefit from using the Internet for business. Researchers agree that the contribution made by the tourism sector in developing economies is substantial. However, SMHEs are noted for their failure to derive optimal benefits from using the Internet for business to improve their competitiveness. This study which seeks to develop a model for use by SMHEs as a guide when making the decision to adopt technology was necessitated by the importance of SMHE’s contribution in the economy of developing countries. This model is based on the examination of existing theories and models such as; the Delone and McLean IS success model (2004), and the ITGI’s (2007) IT governance focus areas model. To elicit the desired outcomes, additional data was collected using questionnaires, interviews, and observations. The collected data was analysed and resulted in the development of a model that can be used by SMHEs in order to derive value from IT and to gain a competitive advantage.

Thesis uses game theory to explain behavior of certain states in the European sovereign-debt crisis. The goal is to find out, if those states use strategies leading to equilibrium i.e. if they maximize their expected utility. Theoretical part is based mainly on repeated games and Bayesian game. Thesis summarizes development of European sovereign-debt crisis and key economic indicators. It constructs a game model of the crisis and further analyses situation of Germany, France, Italy, Spain and Greece as players in the game. The game model is then tested on key conflict situations such as relations of France and Germany, first Greek bailout negotiations or Spanish bank bailout negotiations. The results show that chosen states do maximize their expected utility in one election period. However maximization of utility in two or more election periods is limited by the parameters of democratic election system - length of election periods and information asymmetry between voters and politicians. The costs of elimination of information asymmetry would be higher than the costs of debt crisis. So even considering the costs of debt crisis the states are in long term equilibrium.

This research involves the design, development, and theoretical demonstration of models resulting in integrated misbehavior resolution protocols for ad hoc networked devices. Game theory was used to analyze strategic interaction among independent devices with conflicting interests. Packet forwarding at the routing layer of autonomous ad hoc networks was investigated. Unlike existing reputation based or payment schemes, this model is based on repeated interactions. To enforce cooperation, a community enforcement mechanism was used, whereby selfish nodes that drop packets were punished not only by the victim, but also by all nodes in the network. Then, a stochastic packet forwarding game strategy was introduced. Our solution relaxed the uniform traffic demand that was pervasive in other works. To address the concerns of imperfect private monitoring in resource aware ad hoc networks, a belief-free equilibrium scheme was developed that reduces the impact of noise in cooperation. This scheme also eliminated the need to infer the private history of other nodes. Moreover, it simplified the computation of an optimal strategy. The belief-free approach reduced the node overhead and was easily tractable. Hence it made the system operation feasible. Motivated by the versatile nature of evolutionary game theory, the assumption of a rational node is relaxed, leading to the development of a framework for mitigating routing selfishness and misbehavior in Multi hop networks. This is accomplished by setting nodes to play a fixed strategy rather than independently choosing a rational strategy. A range of simulations was carried out that showed improved cooperation between selfish nodes when compared to older results. Cooperation among ad hoc nodes can also protect a network from malicious attacks. In the absence of a central trusted entity, many security mechanisms and privacy protections require cooperation among ad hoc nodes to protect a network from malicious attacks. Therefore, using game theory and evolutionary game theory, a mathematical framework has been developed that explores trust mechanisms to achieve security in the network. This framework is one of the first steps towards the synthesis of an integrated solution that demonstrates that security solely depends on the initial trust level that nodes have for each other.

The thesis deals with the question of militarization and weaponization of the outer space and it analyse the actor's behaviour regarding space militarization and weaponization. The aim of the thesis is to find out whether the key actors cooperate or not in dealing with the use of the outer space. The relations between the key actors are analysed from the perspective of the game theory, particularly with the two models of behaviour: prisoner's dilemma and the tragedy of the commons. These models are used based on the assumption that they best describe the relations between actors in international relations as either cooperative or competitive. The aim is to evaluate whether these two models are valid in researching the behaviour of the key actors in the question of militarization of space. The analysed actors are the United States, Russia and China, as these are the three most important and successful space-faring nations with the biggest potential in the future of space exploration. Analysing their relations, the thesis attempts to evaluate whether the two models of the game theory are valid or not. For evaluating the prisoner's dilemma, bilateral relations are analysed, for the tragedy of the commons, their multilateral relations are analysed. What we learn from the analysis is that both models...

The thesis models interactions in the system of states. Fundamental research question asked what consequences for success of strategies and prospects of cooperative behavior have particular settings and properties of the system. Thesis includes two features peculiar to international relations that did not appear anywhere else before: (i) determination of interaction occurrence with help of distance and power; and (ii) emergence of (dis)trust out of the previous interactions. The model is based on three elements: agents, environment, and rules. Players interacted in the Hobbesian Prisoner's Dilemma environment as described by realists, but thanks to payoff shift representing emergence of (dis)trust I also formalized constructivist argument of different cultures of anarchy and of mutually constitutive agent-structure relationship. Multi-agent computer simulations set within the abductive reasoning framework were chosen because lack of heterogeneous enough data and impossibility of experiments made this data generating method a necessity. The source code is written in C#. I translated 62 Axelrod's behavioral rules and then added several others that seemed promising. Three new strategies mirroring usual behavior of states were proposed too. To secure robustness of the results, application was run...

Examination of empirical research confirmed that climate change is a complex problem of anthropological origin and revealed the need for a management framework to facilitate strategic decisions aimed at mitigating a rise in global temperatures of 2-°C linked to irresponsible and unsustainable business practices. The purpose of this simulation study was to develop a management framework of resilience, robustness, sustainability, and adaptive-capacity (RRSA) for organizations viewed as complex systems to address the current unsustainable state. As such, the evolutionary-RRSA prisoner's dilemma (PD) simulation was developed using an evolutionary game theory approach to agent based modeling and simulation, to generate data. Regression analyses tested the relationships between organizational resilience (x1), robustness (x2), and sustainability (x3) as independent variables, and the dependent variable of adaptive capacity (y) for cooperative and defective strategies. The findings were that complex nonlinear relationships exist between resilience, robustness, sustainability, and adaptive-capacity, which is sensitive to initial conditions and may emerge and evolve from combinations of cooperative and defective decisions within the evolutionary RRSA PD management tool. This study resulted in the RRSA management framework, a cyclical 4-phased approach, which may be used by climate governance leaders, negotiators, and policy-makers to facilitate strategy to move global climate change policy forward by guiding bottom-up consumption and production of GHGs, thereby improving adaptive-capacity, while mitigating an increase in global temperatures of 2-°C, which in turn would improve global socio-economic conditions.