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Travel Demand Management (TDM) is now considered one of the most important aspects of transportation planning and operation. The prime objective of TDM is to develop a sustainable transportation system utilizing the existing infrastructure. It is now a well known fact that excessive use of single occupancy vehicle causes numerous problems like traffic congestion, environmental pollution etc. Thus, from TDM perspective, it is of great importance to analyze travel behaviour in order to influence people to reduce car use and choose more sustainable modes such as carpool, public transit, park & ride, walk, bike etc. This study attempts an in-depth analysis of commuting mode choice behaviour using workplace commuter survey data from the City of Edmonton. Unlike traditional mode choice models, this study uses both instrumental and latent variables to better understand the choice process and analyzes their sensitivities with respect to TDM policies. / Transportation Engineering

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We follow the approach of expressive voting and consider that voters with more extreme ideology can enjoy higher utility after voting. However, along with effect of ideology, voters also take the difference of his ideology and candidate¡¦s into account. Given the above assumptions, two candidates choose their ideology before voters decide whether and for whom to vote. Two candidates¡¦ ideology converges to the middle point if voters¡¦ utility generated by expressive voting approach is less important than by instrumental voting approach. In the opposite, two candidates¡¦ ideology diverge and the voters with mild ideology refuse to vote in point if voters¡¦ utility generated by expressive voting approach is more important. We examine the ANES data of ten U.S. presidential elections from 1972 to 2008. The nested logit model is used to estimate the corresponding coefficients of voters¡¦ utility generated by expressive voting approach and instrumental voting approach. The data supports our conjecture that voters with more extreme ideology are more likely to cast their votes.

Made available in DSpace on 2014-06-12T17:21:58Z (GMT). No. of bitstreams: 2 arquivo6593_1.pdf: 1372457 bytes, checksum: 7d328b5860db2137060c9694c0610e5c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Essa dissertação é dividida em dois ensaios. O primeiro objetiva caracterizar a demanda por medicamentos no Brasil. Para isso é feita uma revisão da literatura sobre o tema e expostas suas particularidades para o caso brasileiro por meio dos microdados da POF 2002-2003. Com isso são estimadas as probabilidades de gastos por categoria de medicamento. Conforme os resultados, em geral, essas probabilidades são crescentes com a renda e o grau de instrução do chefe da família. Contudo, outras características como raça, região e idade possuem relevantes efeitos sobre essas probabilidades, onde isso dependerá também do medicamento adquirido. O segundo ensaio visa apresentar como se dá o acesso aos medicamentos pelos brasileiros. Para tanto são aplicados modelos de Escolha discreta, para em seguida, com os dados da PNAD-Saúde 2009, a partir de estimações por Multinomial Logit e Nested Logit, realizar inferências sobre a tomada de decisão de consumo dos indivíduos. Os resultados sugerem que a renda, o grau de instrução e o tipo de doenças infringidas são fatores relevantes. Onde a presença deste último fator afeta diretamente a tomada de decisão de consumo dos brasileiros, principalmente, no caso das doenças mais danosas à saúde

Die vorliegende Arbeit besteht aus vier Aufsätzen, die sich mit der Modellierung von Markenwahlverhalten und Markentreue beschäftigen. Der erste Aufsatz gibt eine Einführung in das Nested Logit Modell und weist auf die Existenz von zwei unterschiedlichen Spezifikationen hin. Das utility maximization nested logit (UMNL) und das non-normalized nested logit (NNNL) Modell besitzen unterschiedliche Eigenschaften, die die Schätzergebnisse beeinflussen. Mit einer Simulationsstudie werden die Konsequenzen der Verwendung verschiedener Softwarepakete demonstriert. Außerdem wird gezeigt, dass nur die UMNL Spezifikation bei Auferlegung einer Parameterrestriktion mit der Zufallsnutzentheorie konform ist. Der zweite Aufsatz untersucht anhand von realen Haushaltspaneldaten den Erfolg einer Familienmarkenstrategie. Die Signaling Theorie liefert einen Rahmen für die dem Markenwahlverhalten zugrunde liegenden psychologischen Prozesse zur Entstehung und Erklärung von produktkategorieübergreifender Markentreue. In einer empirischen Studie wird untersucht, inwieweit in einer Kategorie markentreue Kunden dieser Marke auch in anderen Produktkategorien treu sind. Es wird ein Markentreue-Hebel-Index entwickelt. Im dritten Aufsatz stehen die psychologischen Determinanten von kategorieübergreifenden Zusammenhängen im Markenwahlverhalten im Mittelpunkt. In einer empirischen Studie wird die Risikoaversion als entscheidender Bestimmungsfaktor von kategorieübergreifender Markentreue untersucht. Die konsumentenspezifische Risikoaversion wird dabei über Innovativeness und Status Quo Bias erfasst. Im vierten Aufsatz wird das Hybride Wahlmodell einem breiten Marketingpublikum vorgestellt. Klassische Wahlmodelle gehen davon aus, dass das beobachtbare Verhalten das Resultat eines nicht spezifizierten Evaluationsprozesses des Individuums ist. Der kausalanalytische Ansatz hingegen erlaubt die Spezifikation nicht direkt messbarer Faktoren als latente Variablen und kann somit Wahlmodelle sinnvoll ergänzen. / This thesis is composed of four essays that pick up topics in brand choice and brand loyalty modeling. The first essay gives an introduction to the nested logit model and points attention to the existence of two different specifications. The utility maximization nested logit (UMNL) model and the non-normalized nested logit (NNNL) model have different properties which impact the estimation results. In a simulation study, the consequences of the usage of different software packages for model estimation on the estimation results is demonstrated. It is also shown that only the UMNL specification with an imposed parameter restriction is consistent with the underlying random utility theory. The second essay investigates the success of an umbrella branding strategy using household panel data. Signaling theory provides a framework for the underlying psychological processes in consumers'' brand choice behavior and can contribute in the formation and explanation of loyalty to the brand in multiple categories. An empirical study determines whether there is a tendency for loyal consumers from one product category to be loyal to the same brand in other product categories as well. Therefore, a cross-category brand loyalty leverage index is developed. In the third essay, consumer-specific psychological determinants of cross-category relations between brand loyal choice decisions are discussed. In an empirical study, the concept of risk aversion is considered as the key determinant of cross-category brand loyalty. Consumers'' risk aversion is derived from their innovativeness and status quo bias. In the fourth essay, the hybrid choice model is introduced to the broad marketing audience. Traditional choice models assume that observable behavior results from an unspecified evaluation process of the observed individual. The causal-analytic approach offers the possibility to specify not directly measurable factors as latent variables, and can thus reasonably supplement choice models.

O presente trabalho procura avaliar a relevância da informação sobre a segurança dos automóveis para os consumidores brasileiros estimando um modelo de demanda logit aninhado controlado pelas notas de zero a cinco estrelas obtidas nos crash tests do Latin NCAP, pesquisa até o momento única no Brasil. Os resultados indicam que a nota nos crash tests são relevantes para a utilidade média dos consumidores com os carros mais bem avaliados mostrando um nível de utilidade maior em relação aos veículos menos seguros. Resultados auxiliares apontam que não há diferença nos preços médios dos modelos avaliados pelo Latin NCAP com notas de uma a cinco estrelas sendo os modelos avaliados com zero estrelas os únicos a apresentarem preços estatisticamente diferentes e mais baratos. Outros resultados obtidos mostram que um aumento no número de automóveis testados de uma determinada montadora aumenta mais que proporcionalmente a probabilidade de um outro automóvel da mesma marca ser avaliado / The present work aims to evaluate how important is the information about car safety for consumers in brazilian market estimating a nested logit demand model using the Latin NCAP\'s grades from zero to five stars as independent variables, yet this research is unique in Brazil. The results obtained show that Latin NCAP\'s grades show some relevance for the consumer\'s mean utiliy as the higher grades exibit higher mean utility levels related to the lowest grades. Auxiliary results show that there is no statistic diference among the car\'s prices evaluated with one to five stars in the crash tests as the automobiles evaluated with zero stars appear as being the cheapest of all. Others results show that an increase in the number of tested vehicles from a given manufacturer raises more than proportionally the probability of a car from this same brand to be tested

Degree awarded (2004): PhDEc, Economics, George Washington University / This research introduces a new theoretical framework for the analysis of access pricing (the prices that networks charge each other for the completion of calls) and the modeling of network interconnection competition. Prior work on two-way access by Armstrong (1998), Laffont, Rey and Tirole (1998), and Carter and Wright (1999), et al has been built on a two-network Hotelling (1929) differentiated competition model applied to network interconnection. The current research develops an alternative approach that is based on a cross-nested logit (CNL) discrete/continuous consumer choice model with a constant elasticity of substitution (CES) calling utility specification. A principal contribution of the new modeling framework is that in addition to being able to analyze interconnection competition among multiple networks, it is designed to incorporate the element of multiple network subscription where consumers may simultaneously subscribed to more than one type of access network. By introducing multiple-network subscription and usage substitution for users subscribed to multiple networks, the analysis allows more general assessments to be made of the impact of access pricing schemes on the degree of competition between interconnected networks. The model is also not restricted to assumptions of homogeneity in calling on the differentiated networks but can incorporate call differentiation according to network type. The model is applied to evaluate the effects of dual network subscription and asymmetric network competition and to assess multi-network competition in an environment served by two mobile networks and a fixed, wireline network. While confirming the results of prior single network subscription analysis, a central finding of the research based on the developed model is that while network competition is intensified when dual network subscription occurs, negotiated access charges between connected networks continue to serve as an instrument of collusion even in cases of non-linear (two-part) consumer tariffs. / Advisory Committee: John Kwoka, Christopher Snyder (Chair), Sumit Joshi

O presente trabalho procura avaliar a relevância da informação sobre a segurança dos automóveis para os consumidores brasileiros estimando um modelo de demanda logit aninhado controlado pelas notas de zero a cinco estrelas obtidas nos crash tests do Latin NCAP, pesquisa até o momento única no Brasil. Os resultados indicam que a nota nos crash tests são relevantes para a utilidade média dos consumidores com os carros mais bem avaliados mostrando um nível de utilidade maior em relação aos veículos menos seguros. Resultados auxiliares apontam que não há diferença nos preços médios dos modelos avaliados pelo Latin NCAP com notas de uma a cinco estrelas sendo os modelos avaliados com zero estrelas os únicos a apresentarem preços estatisticamente diferentes e mais baratos. Outros resultados obtidos mostram que um aumento no número de automóveis testados de uma determinada montadora aumenta mais que proporcionalmente a probabilidade de um outro automóvel da mesma marca ser avaliado / The present work aims to evaluate how important is the information about car safety for consumers in brazilian market estimating a nested logit demand model using the Latin NCAP\'s grades from zero to five stars as independent variables, yet this research is unique in Brazil. The results obtained show that Latin NCAP\'s grades show some relevance for the consumer\'s mean utiliy as the higher grades exibit higher mean utility levels related to the lowest grades. Auxiliary results show that there is no statistic diference among the car\'s prices evaluated with one to five stars in the crash tests as the automobiles evaluated with zero stars appear as being the cheapest of all. Others results show that an increase in the number of tested vehicles from a given manufacturer raises more than proportionally the probability of a car from this same brand to be tested

The aim of this study was to develop a framework to model travel choice behavior in order to estimate intercity travel demand at nation-level in the United States. Nested and mixed logit models were developed to study national-level intercity transportation in the United States. A separate General Aviation airport choice model to estimates General Aviation person-trips and number of aircraft operations though more than 3000 airports was also developed. The combination of the General Aviation model and the logit models gives the capability to estimate a full spectrum of intercity travel demand in the United States. The logit models were calibrated using a nationwide revealed preference survey (1995 American Travel Survey). Separate models were developed for business and non-business trip purposes. An airport choice model is integrated into the mode choice model to estimate both the market share between any origin-destination pair and other modes of transportation, and the market share split between airports associated with the origin-destination pairs. The explanatory variables used in the utility functions of the models are travel time, travel cost, and traveler's household income. The logit models are used to estimate the market share of automobile and commercial air transportation between 3091 counties and 443 commercial service airports in the United States. The model was also used to estimate market share for on-demand air taxi services. Given an input county-to-county trip demand table, the models were used to estimate county-to-county travel demand by automobile and commercial airline between all counties and commercial service airports in the United States. The model has been integrated into a computer software framework called the Transportation Systems Analysis Model (TSAM) that estimates nationwide intercity travel demand in the United States. / Ph. D.