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This dissertation develops models of charitable giving in the presence of uncertainty. The model of chapter 2 studies a two-stage signaling game of charitable donations with two players: a charity manager and a wealthy donor. A representative charity manager, who is perfectly informed, collects a donation from a representative donor, who has imperfect information about the manager's types. The manager uses the donation to produce a public good, and in the process decides whether to create waste in order to obtain a personal gain. I solve for separating and pooling sequential equilibria of the game, and employ the Intuitive Criterion of Cho & Kreps (1987) as a refinement to deal with the problem of multiple equilibria. I find that there exists no fully separating equilibrium in which the donor can discern all possible manager types. In addition, the results suggest that the amount of the initial donation may help the donor to induce the manager to reveal his true type. In chapter 3, I analyze the effect of competitive pressures in the philanthropic sector. I find evidence in support of market systems acting as a disciplining device, which induces the manager to play strategies that increase social welfare. Chapter 4 uses an alternative to expected utility theory, known as Choquet expected utility, to model the interaction between a wealthy donor and a charity manager in the presence of uncertainty. / Economics

Over the past several decades, moose (Alces alces) populations in New England have been in decline due to winter tick (Dermacentor albipictus) parasitism. Winter ticks have been known to infest moose, with over 90,000 ticks being recorded on a single moose. These severe infestations, known as epizootics, are associated with high annual calf mortality rates (> 50%) and reductions in annual productivity (adult calving and twinning rates < 60% and 5%, respectively). Given this, it is increasingly important to effectively monitor moose and winter ticks to address consistent population decline of moose due to winter tick epizootics. The objectives of this work were to measure off-host winter tick abundance and associated environmental variables and compare off-host tick abundance in relation to moose abundance. To assess moose and winter tick abundance, I used a combination of camera traps and winter tick sampling. I set an array of 60 cameras across central-western Massachusetts, which contribute data to the Northeast Wildlife Monitoring Network. I used a plot-based sampling strategy that is effective for heterogenous habitat types to sample winter ticks at sites in western and central Massachusetts as well as the White Mountain National Forest and Umbagog National Wildlife Refuge in New Hampshire. The Penobscot Nation developed the tick sampling approach and contributed additional winter tick data from their sovereign trust lands in Maine. I used N-mixture models to generate estimates of tick abundance for each of the three study areas. Results from this study can inform monitoring strategies for ticks, predict epizootic severity, and develop tools to mitigate threats to moose. This is important for managers looking to prevent further declines in moose populations due to winter ticks and tribes seeking to maintain populations for sustenance.

This dissertation is comprised of three essays that generate methods to measure the ex-ante economic impacts of agriculture technology innovations. The first essay entitled 'Valuing Intellectual Property Rights in an Imperfectly Competitive Market: A Biopharming Application' presents a method for valuing the intellectual property rights (IPRs) for an innovation that lowers product production costs below those associated with the patented process of a monopolist. The application to Glucocerebrosidase enzyme from transgenic tobacco suggests an intellectual property rights (IPRs) value of about $1.75 billion. Despite the innovator's market power, significant surplus gains also accrue to consumers. Further, U.S. antitrust laws that prohibit IPRs acquisition by the current monopolist increase consumer welfare by almost 50 percent. The second essay entitled 'Ex-Ante Analysis of the Benefits of Transgenic Drought Tolerance Research on Cereal Crops in Low-Income Countries' develops a framework to examine the ex-ante benefits of transgenic research on drought in eight low-income countries, including the benefits to producers and consumers from farm income stabilization and the potential magnitude of private sector profits from IPRs. The framework employs country-specific agroecological-drought risk zones and considers both yield increases and yield variance reductions when estimating producer and consumer benefits from research. Benefits from yield variance reductions are shown to be an important component of aggregate drought research benefits, representing 40 percent of total benefits across the eight countries. Further, estimated annual private sector benefits of $US 178 million suggest that significant incentives exist for private sector participation in transgenic drought tolerance research. The third essay entitled 'Ex-Ante Evaluation of Alternative Strategies to Increase the Stability of Cropping Systems in Eastern and Central Africa' examines the ex-ante economic impact of transgenic drought resistance maize breeding and of conventional maize, millet and sorghum drought resistance breeding in Kenya, Uganda, and the Amhara region in Ethiopia. An expected utility framework is combined with a partial equilibrium model and a spatial drought risk zonation scheme to estimate benefits from mean yield increases and yield variance reductions at the market level as well as at the household level for maize, millet and sorghum producers in the administrative regions of each country. Results suggest that annual ex-ante benefits of $87 million, $6.8 million and $4.8 million can be generated from public sector conventional breeding research on maize, sorghum and millet, respectively. Private sector transgenic drought tolerance research may also generate substantial benefits of $97 million for maize producers and consumers, particularly through the reduction of yield variance arising from drought, and an additional $21 million as profits from intellectual property rights protection. / Ph. D.

This thesis investigates the application of an iterative leakage-based precoding algorithm to practical multiuser-MIMO systems. We consider the effect of practical impairments including imperfect channel state information, transmit antenna correlation, and time-varying channels. Solutions are derived which improve performance of the algorithm with imperfect channel state information at the transmitter by leveraging knowledge of the second-order statistics of the error. From this work we draw a number of conclusions on how imperfect channel state information may impact the system design including the importance of interference suppression at the receiver and the selection of the number of co-scheduled users. We also demonstrate an efficient approach to improve the convergence of the algorithm when using interference-rejection-combining receivers. Finally, we conduct simulations of an LTE-A system employing the improved algorithm to show its utility for modern communication systems. / Master of Science

Many problems involving decision making withimperfect information can be modeled as extensive games. Onefamily of state-of-the-art algorithms for computing optimal playin such games is Counterfactual Regret Minimization (CFR).The purpose of this paper is to explore the viability of CFRalgorithms on the board game Stratego. We compare differentalgorithms within the family and evaluate the heuristic method“imperfect recall” for game abstraction. Our experiments showthat the Monte-Carlo variant External CFR and use of gametree pruning greatly reduce training time. Further, we show thatimperfect recall can reduce the memory requirements with only aminor drop in player performance. These results show that CFRis suitable for strategic decision making. However, solutions tothe long computation time in high complexity games need to beexplored. / Många beslutsproblem med dold informationkan modelleras som spel på omfattande form. En familj avledande algoritmer för att beräkna optimal strategi i sådana spelär Counterfactual Regret Minimization (CFR). Syftet med dennarapport är att undersöka effektiviteten för CFR-algoritmer ibrädspelet Stratego. Vi jämför olika algoritmer inom familjen ochutvärderar den heuristiska metoden “imperfekt minne” för spelabstraktion.Våra experiment visar att Monte-Carlo-variantenExternal CFR och användning av trimning av spelträd kraftigtminskar träningstiden. Vidare visar vi att imperfekt minne kanminska algoritmens lagringskrav med bara en mindre förlust ispelstyrka. Dessa resultat visar att CFR är lämplig för strategisktbeslutsfattande. Lösningar på den långa beräkningstiden i spelmed hög komplexitet måste dock undersökas. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm

This PhD is a practice as research interrogation of the emancipatory potential of the idea of imperfection. It is framed around the key leading question: ‘How can the generation of imperfect praxis – cultural production in and through social dialogues challenging notions of technical expertise – affirm emancipatory value in a film practice? The thesis documents the development of a participatory film practice, operating in-between d.i.y subcultural activity and practice as research. The film component of the submission engages with the problems involved in representing and authenticating the collective dimension of participatory filmmaking. The emancipatory potential of imperfection has been explored via a broad range of interdisciplinary participatory practices. The core project is Imperfect Cinema, an open-access micro-cinema collective, which navigated the intersection between film and do-it-yourself punk. This interplay between the contested idea of punk and its inherent activism, with the democratic/accessible implications of audio-visual media, is seen as an exemplary site for examining, and dismantling the boundaries between disciplines. In this sense, the nature of the work can be seen as being ‘in-disciplinary’ (Rancière 2008), requiring a mobility and responsiveness to the emergence of contemporary participatory and collaborative processes. The concept of imperfection draws from punk as a set of d.i.y methodological practices and is key to understanding and developing participatory cinema. Imperfection, as a generative conceptual tool, can be described as incorporating and examining methods ‘against methods’ (Feyerabend 1988) in order to acknowledge the uncertainty and fluidity of participatory work. This forms my understanding of what I term imperfect praxis. This praxis requires the emancipatory potential of imperfection to be easily communicable and accessible to different kinds of participants. The emergence of imperfect praxis developed out of collective social spaces where a kind of knowledge can be explored through collaborative and participatory interactions and dialogues, situated and understood through historical, contextual, personal and shared experiences. This thesis consequently represents a ‘moment in time’ in my methodological development, providing me with the structure to identify and disseminate the practice as research.

This thesis investigates the use of Bayesian analysis upon an opponent's behaviour in order to determine the desired goals or strategy used by a given adversary. A terrain analysis approach utilising the A* algorithm is investigated, where a probability distribution between discrete behaviours of an opponent relative to a set of possible goals is generated. The Bayesian analysis of agent behaviour accurately determines the intended goal of an opponent agent, even when the opponent's actions are altered randomly. The environment of Poker is introduced and abstracted for ease of analysis. Bayes' theorem is used to generate an effective opponent model, categorizing behaviour according to its similarity with known styles of opponent. The accuracy of Bayes' rule yields a notable improvement in the performance of an agent once an opponent's style is understood. A hybrid of the Bayesian style predictor and a neuroevolutionary approach is shown to lead to effective dynamic play, in comparison to agents that do not use an opponent model. The use of recurrence in evolved networks is also shown to improve the performance and generalizability of an agent in a multiplayer environment. These strategies are then employed in the full-scale environment of Texas Hold'em, where a betting round-based approach proves useful in determining and counteracting an opponent's play. It is shown that the use of opponent models, with the adaptive benefits of neuroevolution aid the performance of an agent, even when the behaviour of an opponent does not necessarily fit within the strict definitions of opponent 'style'.

<p align="justify">Computer Science is currently facing a grand challenge : finding good design practices for embedded systems. Embedded systems are essentially computers interacting with some physical process. You could find one in a braking systems or in a nuclear power plant for example. They present several design difficulties : first they are reactive systems, interacting indefinitely with their environment. Second,they must satisfy real-time constraints specifying when they should respond, and not only how. Finally, their environment is often deeply continuous, presenting complex dynamics. The formal models of choice for specifying such systems are timed and hybrid automata for which model checking is pretty well studied.</p> <p align="justify">In a first part of this thesis, we study a complete design approach, including verification and code generation, for timed automata. We have to define a new semantics for timed automata, the AASAP semantics, that preserves the decidability properties for model checking and at the same time is implementable. Our notion of implementability is completely novel, and relies on the simulation of a semantics that is obviously implementable on a real platform. We wrote tools for the analysis and code generation and exemplify them on a case study about the well known Philips Audio Control Protocol.</p> <p align="justify">In a second part of this thesis, we study the problem of controller synthesis for an environment specified as a hybrid automaton. We give a new solution for discrete controllers having only an imperfect information about the state of the system. In the process, we defined a new algorithm, based on the monotonicity of the controllable predecessors operator, for efficiently finding a controller and we show some promising applications on a classical problem : the universality test for finite automata.

An aspect of the Romance languages that defies neat linguistic analysis is tense usage. In particular, students of Romance languages as well as grammarians have found it difficult to provide a consistent explanation for the imperfect - preterite opposition. Two main points of contention concern (i) the question of whether the two forms have an inherent aspectual content and (ii) the structure and role of lexical aspectual information in determining the overall meaning of a sentence. While the attempts at explaining French and Spanish usages of the imperfect and the preterite are numerous, hardly any work has been done in the interpretation of Romanian data. Furthermore, a general assumption that the same form - function opposition holds across Romance languages has led to cross-linguistic differences rarely being examined. I argue that the imperfect and the preterite do have an inherent aspectual content. However, in opposition to previous accounts, I maintain that the preterite does not provide a ‘closed’ viewpoint and that an atelic eventuality described by the verb phrase in the preterite can continue up to the present moment. I propose a description of the imperfect - preterite opposition that includes finer distinctions of lexical aspect based on its constituent stage structure. These finer lexical aspectual distinctions allow the identification of an area of divergence in the use of the two forms in French, Spanish, and Romanian: the preterite was found to be used more widely with states in Romanian than in French and Spanish.