Cloud computing is a multi billion dollar industry, based around outsourcing the provisioning and maintenance of computing resources. In particular, Infrastructure as a Service (IaaS) enables customers to purchase virtual machines in order to run arbitrary software. IaaS customers are given the option to purchase priority access, while providers choose whether customers are preempted based on priority level. The customer decision is based on their tolerance for preemption. However, this decision is a reaction to the provider choice of preemption policy and cost to purchase priority. In this work, a non-cooperative game is developed for an IaaS system offering resource reservations. An unobservable $M|G|1$ queue with priorities is used to model customer arrivals and service. Customers receive a potential priority from the provider, and choose between purchasing a reservation for that priority and accepting the lowest priority for no additional cost. Customers select the option which minimizes their total cost of waiting. This decision is based purely on statistics, as customers cannot communicate with each other. This work presents the impact of the provider preemption policy choice on the cost customers will pay for a reserved instance. A provider may implement a policy in which no customers are preempted (NP); a policy in which all customers are subject to preemption (PR); or a policy in which only the customers not making reservations are subject to preemption (HPR). It is shown that only the service load impacts the equilibrium possibilities in the NP and PR policies, but that the service variance is also a factor under the HPR policy. These factors impact the equilibrium possibilities associated to a given reservation cost. This work shows that the cost leading to a given equilibrium is greater under the HPR policy than under the NP or PR policies, implying greater incentive to purchase reservations. From this it is proven that a provider maximizes their potential revenue from customer reservations under an HPR policy. It is shown that this holds in general and under the constraint that the reservation cost must correspond to a unique equilibrium. / 2020-06-03T00:00:00Z

Os leilões na Internet têm ganhado muita popularidade, tornando-se uma das mais bem sucedidas formas de comércio eletrônico na atualidade. Apresento um modelo teórico para descrever um leilão ascendente, semelhante ao que ocorre na eBay, e verifico suas previsões comportamentais através de dois experimentos. Os resultados mostraram um distanciamento grande entre as previsões teóricas e o que foi observado na prática, no que se refere às estratégias utilizadas, mas acredito que isso se deva à falta de experiência dos participantes dos experimentos. Desenvolvo, então, programas que automatizam a coleta de dados de leilões de selos na eBay e analiso as variáveis que influenciam preços, número de compradores e lances iniciais (preços mínimos). Não houve surpresas em tal análise, no sentido de observar-se resultados contra-intuitivos, mas destaco a reputação dos vendedores como fator relevante para a determinação de preços finais e número de compradores participantes. Além disso, também destaco a ocorrência da submissão tardia de lances, fenômeno recorrente nos leilões na Internet. Proponho, por fim, um método simples que busca determinar o tipo de modelo de leilão, se de valor comum ou de valor privado, e aplico o método nos dados obtidos dos leilões de selos. O resultado foi o de que os leilões analisados estão enquadrados no modelo de valor comum. / Online auctions are one of the most popular and successful types of electronic commerce nowadays. I present a theoretical framework to address the kind of ascending auction implemented at eBay, and I check its predictions through two experiments. The results of the experiments did not confirm the theory, but I believe this is due to the bidders’ lack of previous experience. I also present an algorithm that automatically gathers data from auctions of stamps at eBay. These data is then used on an exploratory analysis that tries to shed some light on the determinants of final prices, minimum bids and the number of bidders. There were no surprises in this analysis, but I would highlight the measurable effect that seller’s reputation has on final prices and the number of bidders. Furthermore, it was possible to observe the occurrence of late bidding. At last, I propose a simple method that determines to which paradigm the on-line auction of stamps at eBay belongs: private value or common value. The result was that the auction of stamps at eBay belongs to the common value paradigm.

Thesis advisor: Kenji Hayao / Thesis advisor: Hiroshi Nakazato / The most stunning example of two historical figures working both together and against one another to fashion a shared goal is the demonstration of power and compromise displayed by Count Camillo Benso di Cavour and Giuseppe Garibaldi during the Sicilian Revolution of 1860 and additional events during the greater Italian Risorgimento. This thesis is an attempt to uncover the bargaining strategies utilized by Cavour and Garibaldi throughout their political interactions as well as reach important conclusions concerning the use of interpersonal relationships to aid, not hinder, the outcome of a common political aim. This case study focuses on the years from 1852 to 1870, but specifically looks at 1859 to 1861, largely considering the theoretical framework of political game theory as outlined by Thomas Schelling. After forming two distinct hypotheses regarding both the competitive and cooperative nature of the two men's relationship, this thesis finds a greater cooperative characteristic to their historic interactions, although both hypotheses contribute to a relationship that formed the state of Italy. / Thesis (BA) — Boston College, 2008. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: International Studies. / Discipline: International Studies Honors Program.

Thesis advisor: Robert Murphy / Thesis advisor: Hiroshi Nakazato / The majority of scholarship surrounding the late 2000s financial crisis explores the enabling factors that contributed to the subprime bubble and caused it to burst. This study’s purpose is to evaluate systemic risk and the near collapse of the financial sector in 2008. Several factors, including derivatives innovation, the rise of a parallel banking industry, and the securitization boom, heightened systemic fragility. I add to financial contagion literature by constructing a stochastic game theory model of institutional decision-making under the auspices of a severe liquidity shortage. Moreover, I will employ this model to evaluate the government’s regulatory program during the crisis. I find that the government’s ad hoc interventions and non-interventions significantly contributed to the atmosphere of uncertainty and exacerbated the crisis’ ill effects. I go on to evaluate the Dodd-Frank Act in light of those conclusions and suggest an alternate method of financial reform. / Thesis (BA) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: International Studies Honors Program. / Discipline: International Studies.

Thesis advisor: Hideo Konishi / Online auctions have many different formats. Each of these affect the ways in which users bid strategically. One example of this is the end-time format. Some sites, like eBay, use a hard close, under which there is a strict end-time and the highest bidder at that time wins. Others, like Amazon, have an extended end-time format. It has been shown that these differences do, in fact, appear to change how bidders behave. This paper uses data obtained from Yahoo! Auctions, where both formats are used, to examine the impact these differences have on the final price of an auction. / Thesis (BA) — Boston College, 2005. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Economics Honors Program.

Game theory is a common tool in modeling human decisions and strategies under various decision environments, with the foundation being the fact that a joint decision from all the individuals (we shall adhere to the term players hereafter) will impact on each other's well being. In this thesis, we shall study how the behaviors of the players affect the performance of the whole system, and shall introduce some measurements to quantify the influence on the system performance. / In the second part, we turn to the consequence of greediness of the players. In a dynamic decision-making process, system inefficiency may be caused by the unwise use of the resources due to the myopia of the decision makers. The loss of efficiency is measured by a ratio termed the Price of Myopia: the value at the greedy solution divided by the optimal value. A specific setting is studied to illustrate the point. Furthermore, we consider the combined effect of selfishness and myopia under a game framework and introduce a new notion, the Price of Isolation to quantify the matter. Some bounds for the price of isolation are established in a dynamic setting of the previous two models. / In the third part, we investigate the influence of cooperation and altruistic behavior of players. The incentive of the players to cooperate, and the impact of cooperation on the members of the coalition and on the whole system are analyzed. We consider a model of resource competition game and find that the system will benefit from the cooperation of players at the expense of some individual members in the coalition. A measurement termed the Price of Socialism is introduced to characterize how much any individual will need to sacrifice for the social optimum. We obtain a tight bound for the price of socialism for our particular model. / The first part is devoted to the study of the loss of system efficiency caused by selfish behavior of the players. We use the notion of the Price of Anarchy and consider two different but intrinsically related game settings to address the issue. One is to consider the cost incurred to the players due to the usage of some shared resources, modeled as the links of a network. Suppose that there are K players and each of them must achieve a given throughput. Furthermore, the unit cost on each link is affine linear in the total flow. Then the price of anarchy for the game can be upper bounded by (3K + 1)/(2 K + 2). The second model is a generalization of Cournot oligopolistic competition, in which the players utilize some shared resources to produce some commodities to sell. Again, suppose there are K players, and the unit costs of the shared resources and the selling prices of the products are all affine linear functions in the amount of demand and supply respectively. Then the price of anarchy is shown to be lower bounded by 1/K. / Wang, Xiaoguo. / Adviser: Shuzhong Zhang. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 104-108). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Le sujet général de cette thèse est la modélisation mathématique des systèmes biologiques. Le principal modèle étudié est le réseau métabolique: une collection d'objets - métabolites, réactions biochimiques, enzymes et gènes - et les relations entre eux, généralement organisées sous forme de graphe.Trois sujets distincts sont couverts. Dans le premier chapitre principal, un algorithme appelé MOOMIN pour «Mathematical explOration of Omics data on a MetabolIc Network» est présenté. C'est un outil informatique permettant d'interpréter les résultats d'une analyse d'expression différentielle à l'aide d'un réseau métabolique. Le résultat de l'algorithme est un changement métabolique, exprimé en termes de réactions supposées avoir subi un changement d'activité, qui correspond le mieux aux données d'expression génique. Le deuxième chapitre principal traite de l'intersection de la théorie des jeux et de l'étude du métabolisme cellulaire. Un nouveau type de modèle est proposé, combinant les principes de la théorie des jeux évolutive à la modélisation par contraintes pour prédire le comportement métabolique. Dans le troisième et dernier chapitre principal, un modèle épidémiologique de l'agent pathogène de la vigne Xylella fastidiosa est présenté et analysé. À l'aide d'une analyse de sensibilité, l'importance relative des paramètres du modèle est évaluée et les résultats sont discutés du point de vue de la lutte contre la maladie / The overall subject of this thesis is mathematical modelling of biological systems. The main model under study is the metabolic network: a collection of objects — metabolites, biochemical reactions, enzymes, and genes — and the relations amongst them, usually organised to form a graph.Three distinct topics are covered. In the first main chapter, an algorithm called MOOMIN for “Mathematical explOration of Omics data on a MetabolIc Network” is presented. It is a computational tool to interpret the results of a differential expression analysis with the help of a metabolic network. The output of the algorithm is a metabolic shift, expressed in terms of reactions that were inferred to have undergone a change in activity, that best aligns with the gene expression data. In the second main chapter, the intersection of game theory and the study of cellular metabolism is discussed. A new type of model is proposed, one that combines the principles behind evolutionary game theory with constraint-based modelling to predict metabolic behaviour. In the third and last main chapter, an epidemiological model of the Xylella fastidiosa grapevine pathogen is presented and analysed. Using sensitivity analysis, the relative importance of the model parameters is evaluated, and the results discussed from the point of view of disease control

This dissertation consists of three chapters. Chapter 1, "Precision of Communication in Coordination Games of Regime Change,'' is in the field of macroeconomics and economics of information. I study a model of regime change in which the government can communicate with different levels of precision as a function of the underlying fundamentals. In the model, higher precision of communication corresponds to a lower dispersion of private information among market participants. I compare a policy of an uncommitted government, which chooses the precision of communication after it learns the realization of fundamentals, to a policy of a committed government, which commits to a state-dependent policy before it learns the realization of fundamentals. I find that an uncommitted government communicates imprecisely for weak fundamentals and precisely for strong fundamentals. In contrast, a committed government communicates precisely for weak fundamentals and imprecisely for strong fundamentals. Consequently, a committed government saves its regime more often than an uncommitted one. An uncommitted government can benefit from a rule that enforces constant precision of communication. Chapter 2, "Multiple Equilibria in Global Games with Varying Quality of Information,'' is a follow up chapter on Chapter 1. I show that global game models can have multiple equilibria if the quality of information available to agents varies with the state of economic fundamentals. First, I construct two examples that illustrate why the quality of information may vary and show that the corresponding information structures support several equilibria. Second, I construct an information structure that supports a given number of equilibria. Very different equilibria can exist simultaneously, even if agents' quality of information is arbitrarily high. The set of possible equilibria can be very similar to the set of equilibria under complete information, even when agents are uncertain about the state of fundamentals and beliefs of other agents. My results have practical implications for the disclosure of information by governments and for our ability to predict the outcome of currency attacks or debt runs based on economic fundamentals. Chapter 3, "Long-Run Price Elasticity of Trade and the Trade-Comovement Puzzle,'' is in the field of international macroeconomics and is coauthored with Lukasz Drozd and Jaromir Nosal. What role do international trade linkages play in transmitting shocks across borders? Analytically, we demonstrate that in a broad class of open economy macroeconomic models, shock transmission crucially depends on dynamic properties of trade elasticity---which is rarely modeled explicitly in business cycle theory. We illustrate the quantitative relevance of this point by exploring the well documented link between trade and comovement in the cross-section of countries, and by relating our theoretical findings to those in the literature. We find that dynamic elasticity does indeed affect the findings in a quantitatively significant way. Hence, our paper advocates for using dynamic elasticity models in contexts that evaluate international business cycle theory vis-a-vis data on cross-country variation of business cycle moments.

This thesis studies three game theoretic models of pricing, in which a seller is interested in optimally pricing and allocating her product or service to a market of agents, in order to maximize her revenue. These markets feature a large number of self-interested agents, who are generally heterogeneous with respect to some payoff relevant feature, e.g., willingness to pay when agents are consumers or private cost when agents are firms. Agents strategically interact with one another, and their actions affect other agents' payoffs, either directly through social influence or competition, or indirectly through a review system. The seller has demand uncertainty and strives to optimize expected discounted revenues. I use either a mean-field approximation or a continuum of agents assumption to reduce the complexity of the problems and provide crisp characterizations of system aggregates and equilibrium policies. Chapter 2 considers the problem of an information provider who sells information products, such as demand forecasts, to a market of firms that compete with one another in a downstream market. We propose a general model that subsumes both price and quantity competition as special cases. We characterize the optimal selling strategy and find that it depends on both mode and intensity of competition. Several important extensions to heterogeneous production costs, information quality discrimination, and information leakage through aggregate actions are studied. Chapter 3 considers the problem of optimally extracting a stream of revenues from a sequence of consumers, who have heterogeneous willingness to pay and uncertainty about the quality of the product being sold. Using an intuitive maximum likelihood procedure, we characterize the solution of consumers' quality estimation problem. Then, we use a mean-field approximation to characterize the transient dynamics of quality estimates and demand. These allow us to simplify and solve the monopolist's problem, and ultimately provide a characterization of her optimal pricing policy. Chapter 4 considers the problem of a seller who is interested in dynamically pricing her product when consumers' utility is influenced by the mass of consumers that have purchased in the past. Two scenarios are studied, one in which the monopolist has commitment power and one in which she does not. We characterize the optimal selling strategy under both scenarios and derive comparisons on equilibrium prices and demands. Our main result is a characterization of the value of price commitment as a function of the social influence level in the market.

At individual level, we adopted the well-known ultimatum game experiment with asymmetric information. By allowing individuals to view historical market information, we study how individuals utilize the market transaction information to help them make decisions under the asymmetric information condition. We testified the History-Consistent Rationality Model, and illustrated that the model is sufficient to yield accurate point predictions that are on average within 5% absolute deviation of the total pie size for every subject behavior in 20 rounds. / At market level, we studied how people evaluate the value of information, and what kind of information revelation mechanism would collectively maximize market efficiency. We examined the prevailing market mechanism and found that there are unavoidable deadweight losses, so we proposed a new model that could eliminate deadweight losses under many market conditions, and designed and conducted experiments to testify our claims. / In this dissertation, we relaxed the perfect information assumption in the marketplace, and studied the reality with asymmetric information from a market scope, and then drill down to decision making model at individual level. / Stiglitz (2009) reviewed the cause of the recent financial tsunami, and claimed that Adam Smith's invisible hand is invisible because it is not actually there: market equilibrium is not constrained Pareto efficient whenever there are information imperfection or asymmetric information, which is always the case in reality. People have conflicts of interests and incentives to provide distorted information, which could be difficult to verify by the other parties, so even if individuals are acting in a perfectly rational way, the outcome is not systemically rational. He concluded that "we need to do a better job of managing our economy, but this will require better research that is less framed by the flawed models of the past, less driven by simplistic ideas, and more attuned to the realities of today." / Lau, Ka William. / Adviser: Ching Chyi Lee. / Source: Dissertation Abstracts International, Volume: 72-04, Section: A, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 122-127). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest dissertations and theses, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.