The dissertation consists of four essays that treat different aspects or the evaluation of public policy. Two essays are applications of the travel cost method. In the first of these, recreational travel to the Swedish coast is studied to obtain estimates of the social benefits from reduced eutrophication of the sea. The second travel cost essay attempts at estimating how the probability that a woman will undergo mammographic screening for breast cancer is affected by the distance she has to travel to undergo such an examination. Using these estimated probabilities, the woman's valuation of the examination is obtained. The two other essays deal with automobile taxation. One essay analyzes how taxation and the Swedish eco-labeling system of automobiles have affected the sale of different car models. The last essay treats the effects of taxes and of scrappage premiums on the life length of cars. / Diss. Stockholm : Handelshögskolan, 1999

An ever increasing demand for instant and reliable information on modern communication networks forces codewords to operate in a non-asymptotic regime. To achieve reliability for imperfect channels in this regime, codewords need to be retransmitted from receiver to the transmit buffer, aided by a fast feedback mechanism. Large occupancy of this buffer results in longer communication delays. Therefore, codewords need to be designed carefully to reduce transmit queue-length and thus the delay experienced in this buffer. We first study the consequences of physical layer decisions on the transmit buffer occupancy. We develop an analytical framework to relate physical layer channel to the transmit buffer occupancy. We compute the optimal code-rate for finite-length codewords operating over a correlated channel, under certain communication service guarantees. We show that channel memory has a significant impact on this optimal code-rate. Next, we study the delay in small ad-hoc networks. In particular, we find out what rates can be supported on a small network, when each flow has a certain end-to-end service guarantee. To this end, service guarantee at each intermediate link is characterized. These results are applied to study the potential benefits of setting up a network suitable for network coding in multicast. In particular, we quantify the gains of network coding over classic routing for service provisioned multicast communication over butterfly networks. In the wireless setting, we study the trade-off between communications gains achieved by network coding and the cost to set-up a network enabling network coding. In particular, we show existence of scenarios where one should not attempt to create a network suitable for coding. Insights obtained from these studies are applied to design a distributed rate control algorithm in a large network. This algorithm maximizes sum-utility of all flows, while satisfying per-flow end-to-end service guarantees. We introduce a notion of effective-capacity per communication link that captures the service requirements of flows sharing this link. Each link maintains a price and effective-capacity, and each flow maintains rate and dissatisfaction. Flows and links update their respective variables locally, and we show that their decisions drive the system to an optimal point. We implemented our algorithm on a network simulator and studied its convergence behavior on few networks of practical interest.

<p>Diss. Stockholm : Handelshögskolan, 2013. Sammanfattning jämte 3 uppsatser.</p>

Made available in DSpace on 2010-04-20T20:48:01Z (GMT). No. of bitstreams: 3 71050100718.pdf.jpg: 12656 bytes, checksum: 70340ae65c49c6fee3a991247dc4ef5b (MD5) 71050100718.pdf.txt: 321921 bytes, checksum: 2a3fd8e10dce647d19b0906c936496e2 (MD5) 71050100718.pdf: 1109092 bytes, checksum: fd5777ca389880dab6d98b5c7c624391 (MD5) Previous issue date: 2008-02-20T00:00:00Z / The main objective of this thesis is to test the hypothesis that utility preferences that incorporate asymmetric reactions between gains and losses generate better results, when applied to the Brazilian market, than the classic Von Neumann-Morgenstern expected utility function. The asymmetric behavior can be computed through the introduction of a disappointment (or loss) aversion coefficient in the classical expected utility function, which increases the impact of losses against gains. This kind of adjustment is supported by recent developments in financial theory, specially those studies that try to solve the violations of the expected utility axioms. The analysis of the implications of such adjustment is made through the comparison of the results regarding the participation of the risky asset (stock market) in the composition of the optimum portfolio (the one that maximizes utility) generated by both types of preferences: expected utility and loss aversion utility functions. The results are then compared with real data from two types of Brazilian investors (pension funds and households) aiming at verifying the capacity of each utility function to replicate real investment data from these investors. The results of the tests show that it is not possible to reject the expected utility function as an adequate representative model for the aggregate behavior of Brazilian pension funds. However, the simulations indicate that this type of function should be rejected as an adequate model to replicate real investment decisions of Brazilian individual investors (households). The behavior of this type of investors can be better replicated by applying a loss aversion utility function. / O principal objetivo deste trabalho é analisar se o uso de preferências que incorporem assimetria na reação do investidor frente a ganhos e perdas permite gerar resultados mais coerentes com o comportamento real de investidores brasileiros na seleção de portfólios ótimos de investimento. Uma das formas de tratar o comportamento assimétrico se dá através da introdução do coeficiente de aversão a perdas (ou ao desapontamento) na função utilidade tradicional, coeficiente este que aumenta o impacto das perdas frente aos ganhos. A aplicação deste ajuste na função utilidade tradicional decorre de recentes avanços na teoria de finanças, mais especificamente daqueles estudos que buscam solucionar as violações dos axiomas da teoria da utilidade esperada, violações estas já demonstradas empiricamente através de testes de laboratório. A análise das implicações do uso deste tipo de função é feita através da comparação dos resultados quanto à participação do ativo com risco (mercado acionário) na composição do portfólio ótimo (aquele que maximiza a utilidade) do investidor gerados por dois tipos de função utilidade: tradicional e com aversão a perdas. Os resultados são comparados com dados reais de participação do mercado acionário nos investimentos totais de dois tipos de investidores brasileiros - fundos de pensão e investidores individuais - visando verificar a adequação dos resultados de cada função em relação ao comportamento destes investidores. Os resultados mostram que não é possível rejeitar a função utilidade tradicional como modelo representativo do comportamento agregado dos fundos de pensão. Por outro lado, as simulações indicam que a função utilidade tradicional deve ser rejeitada como modelo representativo do comportamento dos investidores individuais, sendo o comportamento destes investidores melhor representado por uma função que incorpora aversão a perdas.

In this thesis I explore a novel context sensitive conceptualisation of civic duty according to which the conduct (or misconduct) of elected officials affects whether eligible voters feel either a duty to vote (DTV) or a duty to abstain (DTA). Specifically, I argue that under conditions of corruption the norm of electoral accountability may override peoples’ sense of DTV in which case they instead feel a DTA. This context sensitive account is contrasted with a Kantian account of civic duty according to which eligible voters feel a duty to always vote, regardless of contextual factors. The empirical results provides tentative support for the claim that corruption not only decreases eligible voters’ sense of DTV but also increases their sense of DTA. This thesis thus contributes not only to the advancement of the conceptualisation of civic duty in relation to voter turnout, but its results also has important implications for how the rational choice perspective approaches the cost/benefit analysis commonly associated with the voting decision. In the latter case these results indicate that abstainers too may act out of duty and can therefore be assumed to gain positive utility from their abstention. However, the possibility that abstention (just as voting) yields unique costs and benefits has to my knowledge never been acknowledged in the rational choice literature on voter turnout. I therefore conclude by presenting a novel suggestion of how the potential costs and benefits of abstention can be incorporated into the calculus of voting.

No description available.

Ein wichtiges Gebiet der Finanzmathematik ist die Bestimmung von Auszahlungsprofilen, die den erwarteten Nutzen eines Agenten unter einer Budgetrestriktion maximieren. Wir charakterisieren optimale Auszahlungsprofile für einen Agenten, der unsicher ist in Bezug auf das genaue Marktmodell. Der hier benutzte Dualitätsansatz führt zu einem Minimierungsproblem für bestimmte konvexe Funktionale über zwei Mengen von Wahrscheinlichkeitsmaßen, das wir zunächst lösen müssen. Schließlich führen wir noch eine zweite Restriktion ein, die das Risiko beschränkt, das der Agent eingehen darf. Wir gehen dabei wie folgt vor: Kapitel 1. Wir betrachten das Problem, die f-Divergenz f(P|Q) über zwei Mengen von Wahrscheinlichkeitsmaßen zu minimieren, wobei f eine konvexe Funktion ist. Wir zeigen, dass unter der Bedingung "f( undendlich ) / undendlich = undendlich" Minimierer existieren, falls die erste Menge abgeschlossen und die zweite schwach kompakt ist. Außerdem zeigen wir, dass unter der Bedingung "f( undendlich ) / undendlich = 0" ein Minimierer in einer erweiterten Klasse von Martingalmaßen existiert, falls die zweite Menge schwach kompakt ist. Kapitel 2. Die Existenzresultate aus dem ersten Kapitel implizieren die Existenz eines Auszahlungsprofils, das das robuste Nutzenfunktional inf E_Q[u(X)] über eine Menge von finanzierbaren Auszahlungen maximiert, wobei das Infimum über eine Menge von Modellmaßen betrachtet wird. Die entscheidende Idee besteht darin, die minimierenden Maße aus dem ersten Kapitel als gewisse "worst-case"-Maße zu identifizieren. Kapitel 3. Schließlich fordern wir, dass das Risiko der Auszahlungsprofile beschränkt ist. Wir lösen das robuste Problem in einem unvollständigen Marktmodell für Nutzenfunktionen, die nur auf der positiven Halbachse definiert sind. In einem Beispiel vergleichen wir das optimale Auszahlungsprofil unter der Risikorestriktion mit den optimalen Auszahlungen ohne eine solche Restriktion und unter einer Value-at-Risk-Nebenbedingung. / Finding payoff profiles that maximize the expected utility of an agent under some budget constraint is a key issue in financial mathematics. We characterize optimal contingent claims for an agent who is uncertain about the market model. The dual approach that we use leads to a minimization problem for a certain convex functional over two sets of measures, which we first have to solve. Finally, we incorporate a second constraint that limits the risk that the agent is allowed to take. We proceed as follows: Chapter 1. Given a convex function f, we consider the problem of minimizing the f-divergence f(P|Q) over these two sets of measures. We show that, if the first set is closed and the second set is weakly compact, a minimizer exists if f( infinity ) / infinity = infinity. Furthermore, we show that if the second set of measures is weakly compact and f( infinifty ) / infinity = 0, then there is a minimizer in a class of extended martingale measures. Chapter 2. The existence results in Chapter 1 lead to the existence of a contingent claim which maximizes the robust utility functional inf E_Q[u(X)] over some set of affordable contingent claims, where the infimum is taken over a set of subjective or modell measures. The key idea is to identify the minimizing measures from the first chapter as certain worst case measures. Chapter 3. Finally, we require the risk of the contingent claims to be bounded. We solve the robust problem in an incomplete market for a utility function that is only defined on the positive halfline. In an example we compare the optimal claim under this risk constraint with the optimal claims without a risk constraint and under a value-at-risk constraint.

Em ecologia, o comportamento dos animais é freqüentemente estudado para entender melhor suas preferências por diferentes tipos de alimento e habitat. O presente trabalho esta relacionado a este tópico, dividindo-se em três capítulos. O primeiro capitulo refere-se à estimação da função da probabilidade da seleção de recurso (RSPF) comparado com um modelo de escolha discreta (DCM) com uma escolha, usando as estatísticas qui-quadrado para obter as estimativas. As melhores estimativas foram obtidas pelo método DCM com uma escolha. No entanto, os animais não fazem a sua seleção baseados apenas em uma escolha. Com RSPF, as estimativas de máxima verossimilhança, usadas pela regressão logística ainda não atingiram os objetivos, já que os animais têm mais de uma escolha. R e o software Minitab e a linguagem de programação Fortran foram usados para obter os resultados deste capítulo. No segundo capítulo discutimos mais a verossimilhança do primeiro capítulo. Uma nova verossimilhança para a RSPF é apresentada, a qual considera as unidades usadas e não usadas, e métodos de bootstrapping paramétrico e não paramétrico são usados para estudar o viés e a variância dos estimadores dos parâmetros, usando o programa FORTRAN para obter os resultados. No terceiro capítulo, a nova verossimilhança apresentada no capítulo 2 é usada com um modelo de escolha discreta, para resolver parte do problema apresentado no primeiro capítulo. A estrutura de encaixe é proposta para modelar a seleção de habitat de 28 corujas manchadas (Strix occidentalis), assim como a uma generalização do modelo logit encaixado, usando a maximização da utilidade aleatória e a RSPF aleatória. Métodos de otimização numérica, e o sistema computacional SAS, são usados para estimar os parâmetros de estrutura de encaixe. / In ecology, the behavior of animals is often studied to better understand their preferences for different types of habitat and food. The present work is concerned with this topic. It is divided into three chapters. The first concerns the estimation of a resource selection probability function (RSPF) compared with a discrete choice model (DCM) using chi-squared to obtain estimates. The best estimates were obtained by the DCM method. Nevertheless, animals were not selected based on choice alone. With RSPF, the maximum likelihood estimates used with the logistic regression still did not reach the objectives, since the animals have more than one choice. R and Minitab software and the FORTRAN programming language were used for the computations in this chapter. The second chapter discusses further the likelihood presented in the first chapter. A new likelihood for a RSPF is presented, which takes into account the units used and not used, and parametric and non-parametric bootstrapping are employed to study the bias and variance of parameter estimators, using a FORTRAN program for the calculations. In the third chapter, the new likelihood presented in chapter 2, with a discrete choice model is used to resolve a part of the problem presented in the first chapter. A nested structure is proposed for modelling selection by 28 spotted owls (Strix occidentalis) as well as a generalized nested logit model using random utility maximization and a random RSPF. Numerical optimization methods and the SAS system were employed to estimate the nested structural parameters.

Submitted by Paulo César Coimbra Lisbôa (pc.coimbra@gmail.com) on 2010-11-11T01:39:34Z No. of bitstreams: 1 PhD_Thesis_Coimbra_v1.pdf: 516617 bytes, checksum: c44a6f3efb7c504da91a6f20e0a95b3f (MD5) / Rejected by Andrea Virginio Machado(andrea.machado@fgv.br), reason: Conforme conversamos, peço fazer a alteração para acesso livre. Andrea on 2010-11-11T14:03:11Z (GMT) / Submitted by Paulo César Coimbra Lisbôa (pc.coimbra@gmail.com) on 2010-11-11T14:17:27Z No. of bitstreams: 1 PhD_Thesis_Coimbra_v1.pdf: 516617 bytes, checksum: c44a6f3efb7c504da91a6f20e0a95b3f (MD5) / Approved for entry into archive by Andrea Virginio Machado(andrea.machado@fgv.br) on 2010-11-16T11:21:16Z (GMT) No. of bitstreams: 1 PhD_Thesis_Coimbra_v1.pdf: 516617 bytes, checksum: c44a6f3efb7c504da91a6f20e0a95b3f (MD5) / Made available in DSpace on 2010-11-17T10:49:20Z (GMT). No. of bitstreams: 1 PhD_Thesis_Coimbra_v1.pdf: 516617 bytes, checksum: c44a6f3efb7c504da91a6f20e0a95b3f (MD5) Previous issue date: 2009-11-30 / Contaminação da confiança é um caso especial de incerteza Knightiana ou ambiguidade na qual o tomador de decisões está diante de não apenas uma única distribuição de probabilidades, mas sim de um conjunto de distribuições de probabilidades. A primeira parte desta tese tem o propósito de fornecer uma caracterização da contaminação da confiança e então apresentar um conjunto de axiomas comportamentais simples sob os quais as preferências de um tomador de decisões é representada pela utilidade esperada de Choquet com contaminação da confiança. A segunda parte desta tese apresenta duas aplicações econômicas de contaminação da confiança: a primeira delas generaliza o teorema de existência de equilíbrio de Nash de Dow e Werlang (o que permite apresentar uma solução explícita para o paradoxo segundo o qual os jogadores de um jogo do dilema dos prisioneiros com um número infinito de repetições não agem de acordo com o esperado pelo procedimento da indução retroativa) e a outra estuda o impacto da contaminação da confiança na escolha de portfolio. / Contamination of confidence is a special case of Knightian uncertainty or ambiguity in which the decision maker faces not simple probability measure but a set of probability measures. The first part of this thesis has the purpose to provide a characterization of the contamination of confidence and then present a simple set of behavioral axioms under which the decision maker’s preference is represented by the Choquet expected utility with contamination of confidence. The second part of this thesis presents two economic applications of the contamination of confidence: the first of them generalizes Dow and Werlang’s existence Theorem of Nash equilibrium under uncertainty (which enables to present an explicit solution to the paradox on which players in a finitely repeated prisoners’ dilemma breaks down backward induction) and the other studies the impact of the contamination of confidence in the portfolio choice.

Em ecologia, o comportamento dos animais é freqüentemente estudado para entender melhor suas preferências por diferentes tipos de alimento e habitat. O presente trabalho esta relacionado a este tópico, dividindo-se em três capítulos. O primeiro capitulo refere-se à estimação da função da probabilidade da seleção de recurso (RSPF) comparado com um modelo de escolha discreta (DCM) com uma escolha, usando as estatísticas qui-quadrado para obter as estimativas. As melhores estimativas foram obtidas pelo método DCM com uma escolha. No entanto, os animais não fazem a sua seleção baseados apenas em uma escolha. Com RSPF, as estimativas de máxima verossimilhança, usadas pela regressão logística ainda não atingiram os objetivos, já que os animais têm mais de uma escolha. R e o software Minitab e a linguagem de programação Fortran foram usados para obter os resultados deste capítulo. No segundo capítulo discutimos mais a verossimilhança do primeiro capítulo. Uma nova verossimilhança para a RSPF é apresentada, a qual considera as unidades usadas e não usadas, e métodos de bootstrapping paramétrico e não paramétrico são usados para estudar o viés e a variância dos estimadores dos parâmetros, usando o programa FORTRAN para obter os resultados. No terceiro capítulo, a nova verossimilhança apresentada no capítulo 2 é usada com um modelo de escolha discreta, para resolver parte do problema apresentado no primeiro capítulo. A estrutura de encaixe é proposta para modelar a seleção de habitat de 28 corujas manchadas (Strix occidentalis), assim como a uma generalização do modelo logit encaixado, usando a maximização da utilidade aleatória e a RSPF aleatória. Métodos de otimização numérica, e o sistema computacional SAS, são usados para estimar os parâmetros de estrutura de encaixe. / In ecology, the behavior of animals is often studied to better understand their preferences for different types of habitat and food. The present work is concerned with this topic. It is divided into three chapters. The first concerns the estimation of a resource selection probability function (RSPF) compared with a discrete choice model (DCM) using chi-squared to obtain estimates. The best estimates were obtained by the DCM method. Nevertheless, animals were not selected based on choice alone. With RSPF, the maximum likelihood estimates used with the logistic regression still did not reach the objectives, since the animals have more than one choice. R and Minitab software and the FORTRAN programming language were used for the computations in this chapter. The second chapter discusses further the likelihood presented in the first chapter. A new likelihood for a RSPF is presented, which takes into account the units used and not used, and parametric and non-parametric bootstrapping are employed to study the bias and variance of parameter estimators, using a FORTRAN program for the calculations. In the third chapter, the new likelihood presented in chapter 2, with a discrete choice model is used to resolve a part of the problem presented in the first chapter. A nested structure is proposed for modelling selection by 28 spotted owls (Strix occidentalis) as well as a generalized nested logit model using random utility maximization and a random RSPF. Numerical optimization methods and the SAS system were employed to estimate the nested structural parameters.