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Several research studies in finance have investigated the effect of financial factors on investment decisions of firms. More recently, researchers have extended conventional models of firm-investment by incorporating a role for financing constraints in determining the firm's investment decision. Empirical work points to overwhelming evidence that in the presence of market imperfections, firm investments become sensitive to the availability of internal cash flows. However, the evidence regarding the patterns of these observed investment-cash flow sensitivities has been ambiguous. In this study we examine the impact of financial development on the sensitivity of firm-level investment to internal cash flow. Using international data from 31 countries over the 1987-1997 period, we find that after controlling for growth opportunities (as measured by Tobin's Q), investment is more sensitive to cash flow for firms in less financially developed countries, indicating higher costs of information problems and lower availability of external capital in such countries. The results are robust to six different measures of financial development. We also find a strong negative relationship between investment cash-flow sensitivity and size (as measured by log of total assets) across countries, though our results are mixed when we investigate this size effect within 6 OECD countries. Overall, these findings are consistent with the notion that smaller firms face greater information costs and are therefore more dependent on internally generated capital for making their investment outlays. Furthermore, we establish a direct connection between the investment cash flow sensitivity studies and a parallel literature on the allocational efficiency of capital markets. We also document important distortionary impacts of using log specifications in the empirical estimation, and of including negative cash flow observations in the sample, which explain the qualitative difference between our results and those of some earlier studies. Finally, our results have important policy implications. Firms that are based in countries with poor standards of financial accounting and information disclosure are found to face greater challenges in accessing external capital markets. These firms are likely to experience high under-investment costs that, at a macro level, would translate into slower economic growth for the country. / Ph. D.

This dissertation consists of three essays on Hedonic price method which is widely used in non-market good evaluation. The first chapter outlines three topics involved and briefly discusses the motivations and methods, as well we some conclusions in each of the following chapters. Chapter 2 uses a conventional first stage hedonic price method to estimate the effect of an aquatic invasive species (Eurasian watermilfoil) on lakefront property values at selected Vermont lakes. Results indicate that as the primary component of total aquatic macrophyte growth in a lake Eurasian watermilfoil significantly and substantially affects lakefront property values. As Eurasian watermilfoil infests a lake, adding to the total macrophyte growth, property values can diminish by <1% to 16% for incremental increases in the infestation level. Hence, policies that successfully prevent infestations have significant economic benefits to owners of lakefront properties and local communities. Chapter 3 focused on a previously unexplored potential impact of 9/11—the impact it may have had on housing prices near mosques. Using a unique dataset that combines the locations of functioning mosques with housing transactions near the time of 9/11, combined with a generalized difference-in-differences framework, we find that housing prices decreased by approximately 7% ($10,559 for the average home) in areas near mosques along the east coast of the U.S. on average in the two years following the attacks. However, on the west coast we find no evidence that 9/11 caused a systematic decrease in housing prices near mosques. Chapter 4 begins from a conventional model of hedonic equilibrium where a nonmarket amenity is conveyed as an attribute of a differentiated traded good. Different metropolitan areas may have different equilibrium price functions due to geographic variation in consumer preferences, income, and production costs. We demonstrate that under relatively mild restrictions on the geographic extent of taste-based sorting, indicator variables for metro areas define "imperfect instruments" that can be used to identify bounds on demand curves. Bounds on demand curves correspond to ranges of partial equilibrium welfare measures for non-marginal changes in environmental quality. We find these ranges to be informative in a preliminary application to evaluating the benefits of reducing cultural eutrophication of lakes in Maine, New Hampshire, and Vermont. The last chapter concludes and discusses the insights for future research. / Ph. D.

On s'intéresse aux jeux infiniment répétés avec observation imparfaite et privée, joués dans des réseaux. Différents réseaux peuvent modéliser les structures d'interaction, d'observation ou de communication d'un jeu répété. La communication est gratuite, et peut être privée ou publique. Différents modèles de jeux répétés sont étudiés, en fonction des réseaux considérés, de la nature de la communication, et du concept d'équilibre étudié. L'objectif principal de cette thèse est d'établir des conditions nécessaires et suffisantes sur les réseaux considérés afin d'obtenir un folk théorème / I study infinitely repeated games with imperfect private monitoring played on networks. Different networks may represent the structures of interaction, of monitoring, and of communication of the repeated game. Communication is costless, and may be either private or public. I study different models of repeated games, depending on the networks considered, on the nature of communication, and on the solution concept. The aim of this thesis is to establish necessary and sufficient conditions on the networks for a folk theorem to hold

Esse trabalho oferece uma avaliação da abundância do papagaio-de-peito-roxo (Amazona vinacea) para 2016 e 2017, combinando contagens em dormitórios ao longo de toda a distribuição da espécie, em escala global, com amostragens replicadas em dormitórios na região oeste de Santa Catarina (WSC), em escala local, Brasil. As contagens em escala global resultaram em 3888 e 4066 indivíduos em 2016 e 2017, respectivamente. As estimativas para o WSC foram de 945 ± 50 e 1393 ± 40 para os mesmos dois anos. Não foi observada nenhuma evidência de crescimento populacional de 2016 para 2017, pois o acréscimo no número de indivíduos foi acompanhado por aumento do esforço amostral em ambas escalas. Quando extrapolamos a abundância no WSC para toda a área de distribuição da espécie, segundo a IUCN, e pressupondo densidade homogênea, obtivemos valores que estão acima da contagem na escala global, mas dentro da mesma ordem de magnitude. Nosso resultado oferece uma base sólida para afirmar que o tamanho populacional global de A. vinacea é de milhares de indivíduos, mas não dezenas de milhares. Realizamos um esforço sistemático para considerar as principais fontes de incerteza na estimativa de abundância da espécie. Cada contagem, tanto na escala local quanto na global, incluíram visitas em todos os dormitórios conhecidos dentro de um intervalo de 10 dias, evitando duplas contagens devido ao movimento dos papagaios entre dormitórios. No WSC, a abundância foi estimada usando um N-Mixture Model implementado em contexto Bayesiano. Apesar de nossa estimativa de tamanho populacional e de área de distribuição serem maiores do que as consideradas pela IUCN, sugerimos que A. vinacea permaneça na categoria “Em Perigo”, até que sejam realizados estudos sobre tendência populacional. / We offer an assessment of Vinaceous parrot (Amazona vinacea) abundance in 2016 and 2017, combining roost counts over the whole range of the species, with a replicated survey of roosts at the local scale, in western Santa Catarina state (WSC), Brazil. The whole range counts amounted to 3888 and 4066 individuals in 2016 and 2017, respectively. The WSC estimates were 945 ± 50 and of 1393 ± 40 individuals, for the same two years. We found no evidence of population growth from 2016 to 2017 because the increase in numbers is accompanied by an increase in observation effort both in WSC and at the whole-range scale. When extrapolating the WSC abundance estimate to the whole IUCN extant range of the species under the simplifying assumption of homogenous population density, we obtain values above the whole-range counts, but within the same order of magnitude. Such result offers a sound basis for putting the global population size of A. vinacea in the thousands of individuals, but not in the tens of thousands of individuals. We made a systematic effort to address key sources of uncertainty in parrot abundance estimation. Each count, at the local or whole-range scale, includes visits to all relevant roosts within less than ten days time to avoid double counting due to movement between roosts. At the local scale, we estimated abundance using an N-Mixture Model of replicated count data, implemented in a Bayesian framework. Even though we estimate a larger population size and a bigger geographic range that those currently reported by the IUCN, we suggest that A. vinacea should remain in the ‘Endangered’ IUCN threat category, pending further investigation of population trends.

本文在不完美財務市場(Imperfect Markets)的假設下，探討採取不同的選擇權的避險策略與對選擇權評價模式的影響，並分析最適避險策略。在這裡所提到的不完美市場指的是無法連續時點的交易、交易時產生交易成本及異質訊息交易者。結果在不完美因素的考量下，其避險策略將不再是完美避險(Delta Hedge)，應適當考慮避險策略。不同於Leland(1985)的分析方式，在此透過不同的避險策略分析去探討比較不完美市場產生的差異，分別以最小變異數避險分析及平均數--變異數避險分析，探討不完美市場對選擇權評價的影響。 不完美市場下選擇權的評價將受其他參數的影響，例如：股票預期報酬及個人風險偏好的影響，本文則嘗試在模型中解釋這兩項因子的角色。 Figlewski(1989a)透過模擬分析探討不完美財務市場對選擇權的影響，並提出不完美市場選擇權的評價影響應考慮對股票預期報酬及個人風險偏好的影響，然而並沒有提出有關的模擬分析及模型的探討。 當採取不同的避險策略考量會有很大的差異，若市場不完美僅是在無法連續性避險則產生的影響相對較小，在最小變異數分析下僅修正相關參數即可，若考量平均數變異數分析將產生買賣價差。但若不完美的因素尚包括交易成本，將明顯影響結果，此時將不再可任意時點避險交易，因為任何交易皆存在交易成本，無限次的交易將使得交易成本趨近無限大。 最後得到調整避險比例時點，結果發現與Whalley 和Wilmott(1997)所推導避險帶為一致的，但在本文模型中將更有彈性的運用，並在數理分析簡化及及計算時間上較為省時的處理。 目次 頁次 第一章 緒論 第一節 前言………………………………………………………………1 第二節 本文內容與架構……………………….……..………………….4 第二章 相關文獻 第一節 完美財務市場……………………………………….……..…….5 第二節 不完美財務市場………………………………………....………7 第三節 不完美避險…………………………………………..….………10 第三章 基本模型分析 第一節 前言…………………..…….………………………………….…11 第二節 市場不完美……………………………………………….…..….11 第三節 最小變異數避險策略……..…………………….……….………14 第四節 平均數變異數避險策略…..………………………………..……20 第五節 極限的情況………………..……………………………….…….26 第四章 交易成本 第一節 前言………………………..……………………………….……29 第二節 最小變異數分析法………….………………………………..…30 第三節 平均數變異數分析法………….……………………..…………33 第四節 極限的情況………………………………………………………36 第五章 不對稱訊息分析 第一節 前言……..………………………………………………..………38 第二節 異質訊息的形成…………………………………………………38 第三節 異質訊息的評價…………………………………………………42 第六章 最適避險區間 第一節 前言………………………………………………………………49 第二節 最佳避險區間……………………………………………………50 第三節 本章小結…………………………………………………………58 第七章 結論與建議……………………………………………………………59 數學附錄 附錄A…………………………………………………………………………60 附錄B…………………………………………………………………………61 附錄C…………………………………………………………………………66 附錄D…………………………………………………………………………68 附錄E……………………………………………………………………….…70 附錄F………………………………………………………………………….71 附錄G…………………………………………………………………………73 附錄H…………………………………………………………………………74 附錄I………………………………………………………………….…….…75 參考文獻 一、國內文獻…………………………………………………………………79 二、國外文獻..…………………………………………………………..……79

American political culture has virtually precluded public discussion about the fundamental weaknesses of capitalism, forcing media reformers to argue defensively that commercial broadcasting is a special case of market failure. This investigation questions the historical inevitability of commercialized mass media structure by examining how the ideology of media professionalism is deployed in public debate over noncommercial uses of mass media resources. The work of John Dewey and Walter Lippmann frame a theoretical understanding of how professional autonomy works in opposition to community, and thus how professionalization works in opposition to a shared democratic sphere. Relying on the fundamental concepts of discursive formations studied in depth by Michel Foucault, three case studies analyze historic moments (the invention of listener support by Lewis Hill, the rise of news reporting by community television volunteers, and the introduction of media literacy in K-12 public education) that offer evidence of discursive breaks within the constructions of professionalism that support commercialization, and what those breaks suggest about the re-instantiation of the historical inevitability of the commercial regime. The conclusion discusses how conditions have led us to a point of deprofessionalization, a state in which media consumers disarm the notion of professionalism before it can be deployed as a governing relation, and how deproduction of authoritative texts effectively contains the power of professionalized norms. INDEX WORDS: Professionalism, Professionalization, Media reform, Commercialization, Noncommercial media, Dewey-Lippmann debate, Lewis Hill, Community television, Media literacy, Deproduction, Deprofessionalization

Construction has a higher injury and fatality rate than most of the other industries. Given this situation, existing research has studied various issues and factors affecting construction safety management and has attempted to use all available methods to improve the construction safety performance. However, the construction accident rate remains among the highest in the United States and the world. The primary objective of this research is to advance autonomous proximity monitoring and hence provide a safer environment for construction workers. In particular, I seek to advance current evaluations of proximity warning technologies to a more robust engineering approach to the design and deployment of autonomous safety monitoring systems. The contributions of the research are demonstrated through specifications, deployments, and testing of proximity monitoring systems for crane loads and falling from height. My research advances current knowledge in three areas. First, I develop specifications for proximity safety monitoring in a sensed environment, built from existing guidelines and expert interviews. Second, I translate the specifications to computer interpretable rules and deploy them in a distributed computing environment. This demonstrates the feasibility of a systems approach and reusability of components to speed deployment. Third, I evaluate the accuracy of the specifications and systems under imperfect data. I further evaluate some approaches to dealing with imperfect data. Collectively, these advances move existing proximity warning research from evaluation of specific systems to an engineering approach to development and deployment of distributed systems with reusable components that explicitly treats imperfect data. / text

In the present work, the Parametric Finite-Volume Theory is expanded by using the inclusion of homogenization processes on mechanical and thermal properties of periodically elastic and viscoelastic composites, with interphase effects. This work introduces models for evaluation of thermal conductivity, coefficient of thermal expansion, elastic and viscoelastic constitutive tensors with unit cell concept applied and periodical boundary conditions in state of generalized plane strain. The current interphase model between inclusion and matrix are considered thin and replaced by equivalent imperfect interfaces. The materials of the interphase are admitted to have lower thermal and mechanical properties. The formulation of the thermal and mechanic homogenization models is based on the traditional strategy of temperature and displacement field expansion in macroscopic and fluctuating components. The effective coefficients of thermal expansion are analytically evaluated using the effective elastic properties and coefficient of thermal expansion of the constitutive phases. Procedures on viscoelastic homogenization are based on Generalized Maxwell model, which allows the assessment of the effective relaxation tensors, providing the effective creep tensors using the Correspondence Principle. The viscoelastic model applied is incremental in time and uses the internal variables formulation. The created models are applied on the solution of many case studies, involving different kinds of composite materials (including size-dependent effects), volume fraction, unit cell geometry and interphase properties influence on the behavior of effective mechanical and thermal properties. The results are compared to analytical and FEM solutions to calculate the method’s efficiency. / No presente trabalho, a versão paramétrica da teoria dos volumes finitos (TVF) é expandida pela incorporação de processos de homogeneização de propriedades térmicas e mecânicas de compósitos periódicos elásticos e viscoelásticos, incluindo efeitos de interfase. O trabalho apresenta modelos para avaliação de condutividade térmica, coeficiente de dilatação térmica, tensores constitutivos elástico e viscoelástico efetivos, considerando o conceito de célula unitária, com condição de contorno periódica em estado plano de deformações generalizado. As interfases existentes entre as inclusões e a matriz são consideradas finas e substituídas por interfaces imperfeitas equivalentes. Os materiais que constituem tais interfases são admitidos com propriedades térmicas e mecânicas inferiores àquelas dos outros constituintes. Os modelos de homogeneização térmica e mecânica são formulados com base na tradicional estratégia de expansão dos campos de temperatura e deslocamentos, respectivamente, em parcelas macroscópica e flutuante. Os coeficientes de dilatação térmica efetivos são avaliados analiticamente em função das propriedades efetivas elásticas e dos coeficientes de dilatação térmica das fases constituintes. Os procedimentos de homogeneização viscoelástico tem como base o modelo de Maxwell generalizado e permitem a determinação dos tensores de relaxação efetivos, a partir dos quais são obtidos os tensores de fluência efetivos através do Princípio da Correspondência. O modelo viscoelástico utilizado é do tipo incremental e utiliza o conceito de variáveis internas. Por fim, os modelos são aplicados na solução de exemplos envolvendo diferentes tipos de materiais compósitos, os quais incluem investigação de efeitos de tamanho, fração volumétrica, geometria da célula unitária, influência das propriedades da interfase sobre as propriedades efetivas térmicas e mecânicas. Os resultados de tais exemplos são comparados com soluções analíticas e com o método dos elementos finitos, demonstrando desempenho dos modelos apresentados.

Esse trabalho oferece uma avaliação da abundância do papagaio-de-peito-roxo (Amazona vinacea) para 2016 e 2017, combinando contagens em dormitórios ao longo de toda a distribuição da espécie, em escala global, com amostragens replicadas em dormitórios na região oeste de Santa Catarina (WSC), em escala local, Brasil. As contagens em escala global resultaram em 3888 e 4066 indivíduos em 2016 e 2017, respectivamente. As estimativas para o WSC foram de 945 ± 50 e 1393 ± 40 para os mesmos dois anos. Não foi observada nenhuma evidência de crescimento populacional de 2016 para 2017, pois o acréscimo no número de indivíduos foi acompanhado por aumento do esforço amostral em ambas escalas. Quando extrapolamos a abundância no WSC para toda a área de distribuição da espécie, segundo a IUCN, e pressupondo densidade homogênea, obtivemos valores que estão acima da contagem na escala global, mas dentro da mesma ordem de magnitude. Nosso resultado oferece uma base sólida para afirmar que o tamanho populacional global de A. vinacea é de milhares de indivíduos, mas não dezenas de milhares. Realizamos um esforço sistemático para considerar as principais fontes de incerteza na estimativa de abundância da espécie. Cada contagem, tanto na escala local quanto na global, incluíram visitas em todos os dormitórios conhecidos dentro de um intervalo de 10 dias, evitando duplas contagens devido ao movimento dos papagaios entre dormitórios. No WSC, a abundância foi estimada usando um N-Mixture Model implementado em contexto Bayesiano. Apesar de nossa estimativa de tamanho populacional e de área de distribuição serem maiores do que as consideradas pela IUCN, sugerimos que A. vinacea permaneça na categoria “Em Perigo”, até que sejam realizados estudos sobre tendência populacional. / We offer an assessment of Vinaceous parrot (Amazona vinacea) abundance in 2016 and 2017, combining roost counts over the whole range of the species, with a replicated survey of roosts at the local scale, in western Santa Catarina state (WSC), Brazil. The whole range counts amounted to 3888 and 4066 individuals in 2016 and 2017, respectively. The WSC estimates were 945 ± 50 and of 1393 ± 40 individuals, for the same two years. We found no evidence of population growth from 2016 to 2017 because the increase in numbers is accompanied by an increase in observation effort both in WSC and at the whole-range scale. When extrapolating the WSC abundance estimate to the whole IUCN extant range of the species under the simplifying assumption of homogenous population density, we obtain values above the whole-range counts, but within the same order of magnitude. Such result offers a sound basis for putting the global population size of A. vinacea in the thousands of individuals, but not in the tens of thousands of individuals. We made a systematic effort to address key sources of uncertainty in parrot abundance estimation. Each count, at the local or whole-range scale, includes visits to all relevant roosts within less than ten days time to avoid double counting due to movement between roosts. At the local scale, we estimated abundance using an N-Mixture Model of replicated count data, implemented in a Bayesian framework. Even though we estimate a larger population size and a bigger geographic range that those currently reported by the IUCN, we suggest that A. vinacea should remain in the ‘Endangered’ IUCN threat category, pending further investigation of population trends.