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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Essays in Industrial Organization and Health Economics:

Genchev, Bogdan Georgiev January 2020 (has links)
Thesis advisor: Julie H. Mortimer / The unifying theme of this dissertation is the growing importance of pharmaceutical products in health care and in society more broadly. The first two chapters use structural and reduced-form models to study the effects of various policies on the choice and utilization of prescription drugs. The third chapter surveys the empirical literature on the competitive effects of a class of pricing arrangements used in the pharmaceutical and many other industries. Chapter 1. One of the criticisms leveled against direct-to-consumer advertising of prescription drugs is that it overemphasizes the use of pharmaceuticals at the expense of other forms of treatment. In “Choice of Depression Treatment: Advertising Spillovers in a Model with Complementarity,” I study how antidepressant TV ads affect demand for psychotherapy. Antidepressant advertising can increase demand for therapy if the products are complements or if advertising has spillover effects. To disentangle the different channels, I develop a discrete-choice demand model that allows for complementarity between products, advertising spillovers, and flexible unobserved preference heterogeneity. Individual-level panel data on treatment choices and price variation allow me to separately identify complementarity and correlated preferences, whereas the average price of TV advertising, used as an instrument, identifies the causal effect of antidepressant ads on demand for each product. The results indicate that even though antidepressants and psychotherapy are substitutes, drug advertising increases demand for therapy through a spillover effect. Allowing for time-invariant and time-varying unobservables that can be correlated across products critically affects the estimated degree of complementarity and advertising elasticities. Chapter 2. While prescription drugs have enabled the cost-effective treatment of a myriad of diseases, many pharmaceuticals come with potential for abuse. The growing use of opioid medications for chronic pain led to widespread misuse, addiction, and skyrocketing overdose death rates. In “Did Plain-Vanilla Prescription Drug Monitoring Programs Reduce Opioid Use? Evidence from Privately Insured Patients,” I explore whether prescription drug monitoring programs (PDMPs) with no registration or use mandates were effective in reducing the utilization of opioid prescription drugs. Exploiting the staggered introduction of such programs between 2008 and 2010, I use difference-in-differences to estimate their causal effect on the number of prescriptions, days supply, and dosage per capita. Based on data from privately insured adults, the estimation results reveal that PDMPs successfully reduced opioid utilization, especially of high-dosage prescriptions. A battery of robustness checks suggests that the estimated effects are caused by the PDMPs and not by confounding factors such as broader trends in health care, attrition, out-of-state purchases, or other anti-opioid policies. Chapter 3. The assumption that buyers pay the same price for each unit of the good they purchase underlies many economic analyses. However, linear pricing is one of many pricing arrangements used in practice. In “Empirical Evidence on Conditional Pricing Practices: A Review,” Julie Holland Mortimer and I review the existing empirical studies on the competitive impact of conditional pricing practices (CPPs), under which the price of a product may depend on a quantity, share, bundling, or other requirement. Examples of CPPs include all-units and loyalty discounts, full-line forcing contracts, and exclusivity arrangements. A common thread unifying the empirical literature is that CPPs often have both procompetitive and anticompetitive effects and that their net effect may depend on the details of the arrangements and the characteristics of the markets in which they are used. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.
32

Specification Tests in Econometrics and Their Application / 計量経済学における特定化検定の理論とその応用

Iwasawa, Masamune 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第19459号 / 経博第528号 / 新制||経||276(附属図書館) / 32495 / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 西山 慶彦, 准教授 奥井 亮, 准教授 高野 久紀 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM
33

Deciphering The Heterogeneity in Transit Service Quality: The Role of Utilitarian, Psychological, Behavioural, and Built Environment Aspects

Eldeeb, Gamal January 2021 (has links)
A thorough understanding of transit customers’ preferences and travel behaviour is fundamental to offering a high-quality urban transportation system. The dominant approach in transit quality literature is rooted in understanding current transit users’ preferences. However, disregarding the heterogeneity in transit customers’ desired quality yields suboptimal conclusions regarding their preferences. Therefore, an effective transit system should strive to understand the broad spectrum of transit and non-transit users’ preferences to increase transit ridership. Towards that end, this research aims at deciphering the heterogeneity associated with transit customers’ service desired quality. The research utilized a primary dataset elicited from an online survey that was part of Hamilton Street Railway (HSR) Public Engagement efforts in Hamilton, Ontario, Canada. The research employed state-of-the-art discrete choice models (e.g., error components logit models, latent class choice models, nested logit models) along with multivariate statistical and spatial analysis. In this respect, this dissertation quantified and unveiled latent heterogeneity in transit customers’ preferences and its implications on their willingness to pay for service improvements through various techniques and specifications. Unlike the conventional classifications for transit customers, our research classifies transit customers into three latent segments: Direct Trip Enthusiastic (DTE), Cost-Sensitive (CS), and Real-time Information Supporter (RIS). The dissertation also investigated and further quantified the influence of subjective psychological factors in shaping transit customers’ preferences towards service attributes. For instance, environmental consciousness is found to be associated with less sensitivity to walking time while higher appreciation to at-stop real-time information provision. Furthermore, the research highlighted how the built environment and its contextual effects influence customers’ travel behaviour while accounting for variations in socioeconomic characteristics. The spatial analysis concluded that the built environment's influence is not equally efficacious over geography. Overall, this research presents a unique contribution to the knowledge of public transit research for practitioners, policymakers, and academia. / Dissertation / Doctor of Philosophy (PhD)
34

Models for heterogeneous variable selection

Gilbride, Timothy J. 19 May 2004 (has links)
No description available.
35

High Dimensional Data Methods in Industrial Organization Type Discrete Choice Models

Lopez Gomez, Daniel Felipe 11 August 2022 (has links)
No description available.
36

Pricing, Variety, and Inventory Decisions in Retail Operations Management

Maddah, Bacel 25 February 2005 (has links)
This dissertation is concerned with decision making in retail operations management. Specifically, we focus on pricing, variety, and inventory decisions, which are at the interface of the marketing and operations functions of a retail firm. We consider two problems that relate to two major types of retail goods. First, we study joint pricing, variety, and inventory decisions for a set of substitutable" items that serve the same need for the consumer (commonly referred to as a "retailer's product line"). Second, we present a novel model of a selling strategy for "complementary" items that we refer to as ``convenience tying," and focus on analyzing the effect of this selling strategy on pricing and profitability. We also study inventory decisions under convenience tying and exogenous pricing. For a product line of substitutable items, the retailer's objective is to jointly determine the set of variants to include in her product line ("assortment"), together with their prices and inventory levels, so as to maximize her expected profit. We model the consumer choice process using a multinomial logit choice model and consider a newsvendor type inventory setting. We derive the structure of the optimal assortment for a special case where the non-ascending order of items in mean consumer valuation and the non-descending order of items in unit cost agree. For this special case, we find that an optimal assortment has a limited number of items with the largest values of the mean consumer valuation (equivalently, the items with the smallest values of the unit cost). For the general case, we propose a dominance rule that significantly reduces the number of different subsets to be considered when searching for an optimal assortment. We also present bounds on the optimal prices that can be obtained by solving single variable equations. Finally, we combine several observations from our analytical and numerical study to develop an efficient heuristic procedure, which is shown to perform well on many numerical tests. With the objective of gaining further insights into the structure of the retailer's optimal decisions, we study a special case of the product line problem with "similar items" having equal unit costs and identical reservation price distributions. We also assume that all items in a product line are sold at the same price. We focus on two situations: (i) the assortment size is exogenously fixed, while the retailer jointly determines the pricing and inventory levels of items in her product line; and (ii) the pricing is exogenously set, while the retailer jointly determines the assortment size and inventory levels. We also briefly discuss the joint pricing/variety/inventory problem where the pricing, assortment size, and inventory levels are all decision variables. In the first setting, we characterize the structure of the retailer's optimal pricing and inventory decisions. We then study the effect of limited inventory on the optimal pricing by comparing our results (in the ``risky case" with limited inventory) with the ``riskless case," which assumes infinite inventory levels. In addition, we gain insights on how the optimal price changes with product line variety as well as demand and cost parameters, and show that the behavior of the optimal price in the risky case can be quite different from that in the riskless case. In the second setting, we characterize the retailer's optimal assortment size considering the trade-off between sales revenue and inventory costs. Our stylized model allows us to obtain strong structural and monotonicity results. In particular, we find that the expected profit at optimal inventory levels is unimodal in the assortment size, which implies that the optimal assortment size is finite. By comparison to the riskless case, we find that this finite variety level is due to inventory costs. Finally, for the joint pricing/variety/inventory problem, we find that even when the retailer has control over the price, finite inventories still restrict the variety level. We also propose several bounds that can be useful in solving the joint problem. We then study a convenience tying strategy for two complementary items that we denote by "primary" and "secondary." The retailer sells the primary item in an appropriate department of her store. In addition, to stimulate demand, the secondary item is offered in two locations: its appropriate department and the primary item's department where it is displayed in very close proximity to the primary item. We analyze the profitability of this selling practice by comparing it to the traditional independent components strategy, where the two items are sold independently (each in its own department). We focus on understanding the effect of convenience tying on pricing. We also briefly discuss inventory considerations. First, assuming infinite inventory levels, we show that convenience tying decreases the price of the primary item and adjusts the price of the secondary item up or down depending on its popularity in the primary item's department. We also derive several structural and monotonicity properties of the optimal prices, and provide sufficient conditions for the profitability of convenience tying. Then, under exogenous pricing, we find that convenience tying is profitable only if it generates enough demand to cover the increase in inventory costs due to decentralizing the sales of the secondary item. / Ph. D.
37

Essays on complementarity : organizational and market changes in agriculture / Essais sur la complémentarité : changements organisationnels et de marché en agriculture

Raza, Saqlain 29 January 2014 (has links)
Cette thèse vise à tester pour l’existence d’effet de complémentarités entre différentes activités économiques dans le secteur agricole. Pour cela, nous mobilisons les deux approches que proposent la littérature, à savoir l’approche par la productivité et l’approche par l’adoption. Nous commençons par une revue de la littérature sur l’économie de la complémentarité, en nous focalisant sur ces deux approches de la complémentarité et ses modèles empiriques. Nous proposons ensuite trois analyses empiriques permettant de tester ces modèles. La première explore les déterminants du choix de marque et/ou de signes des qualité par les petites coopératives agricoles françaises, avec un focus particulier sur la coexistence de ces deux signes. La seconde fournit un test direct de complémentarité entre labels et marques en recourant à l’approche par l’adoption. En estimant un probit multinomial, il est en effet possible de séparer l’effet de complémentarité de celui de l’hétérogénéité inobservable. La troisième introduit l’approche par la productivité, en sus de l’approche par l’adoption, pour tester de cet eet de complémentarité dans les systèmes de polyculture élevage adoptés par les petits exploitants de la province du Pendjab au Pakistan. / The main objective of this thesis is to test for complementarity between different economic activities in agriculture. To do this, we have recourse to the two approaches proposed by the literature, i.e. the productivity approach and the adoption approach. First, we review the economics of complementarity and analyze the different empirical models to test for complementarity. Then, we propose three empirical analyses testing these models. The first examine closely the drivers of the branding and labeling strategies from French small agricultural co-operatives, with a focus on the coexistence of both quality signals. The second directly test for complementarity between branding and labeling using the adoption approach, by estimating a multinomal probit. This allow us to separate what is really due to complementarity and what is caused by unobserved heterogeneity. Third, in addition to adoption approach, we test for complementarity using a productivity approach in the mixed farming systems adopted by smallholder farmers in Punjab, Pakistan.
38

Não são só 20 centavos: efeitos sobre o tráfego da Região Metropolitana de São Paulo devido a redução na tarifa de ônibus financiada pelo aumento da CIDE nos combustíveis da cidade de São Paulo / It is not only 20 cents: effects on traffic in the Metropolitan Region of São Paulo due to reduction in bus fare financed by increased fuel tax in São Paulo city

Barcellos, Thaís Mendonça 26 June 2014 (has links)
Em junho de 2013, o reajuste de R$ 0,20 na tarifa de ônibus gerou uma série de manifestações populares no país que acabaram fazendo alguns governos, como o da cidade de São Paulo, voltarem atrás e arcarem com essa diferença com as empresas de ônibus. Visto isso, o prefeito de São Paulo, Fernando Haddad, propôs uma política de municipalização de um tributo imposto sobre a gasolina, a CIDE, para financiar o transporte público urbano. Nesse contexto, foi encomendada uma pesquisa a Fundação Getúlio Vargas para responder a magnitude do impacto desse subsídio cruzado entre usuários do transporte privado e coletivo. Esse trabalho utiliza o resultado encontrado por essa pesquisa para responder qual o efeito sobre o tráfego da Região Metropolitana de São Paulo utilizando dados da Pesquisa de Origem e Destino de 2007. Os resultados encontrados mostram que a política de subsídio cruzado proporciona um baixo deslocamento no fluxo dos modos de transporte. Além disso, a análise de bem estar da política mostra que os mais favorecidos são os indivíduos de baixa renda. A estimação é feita com base em dois modelos de escolha discreta (Multinomial e Mixed Logit), separada por dois motivos de viagem: trabalho e estudo. E, as simulações de deslocamento de demanda utilizam dois valores de tributos, R$ 0,10 e R$ 0,50. / In June 2013, the increase of 0.20 BRL in bus fare has emerged a series of popular demonstrations in the country that ended up making some governments, such as the city of São Paulo, backtrack and pay out this difference with the buses company. So, the mayor of São Paulo, Fernando Haddad, proposed a policy of decentralization of a tax imposed on gasoline, CIDE, to finance urban public transport. In this context, a report was commissioned to Fundação Getúlio Vargas to respond the magnitude of the impact of cross-subsidy between users of private and collective transport. This work uses the results found in this report to answer the effect on traffic in the Metropolitan Region of São Paulo using data from the Source and Destination Survey of 2007. Results show that the cross-subsidy policy provides a low offset in the flow modes of transport. Moreover, the analysis of welfare policy shows that the most favored are the low-income individuals. The estimation is based on two discrete choice models (Multinomial and Mixed Logit), separate for two reasons of trips: work and study. And the simulations of displacement demand use two values of taxes, 0.10 and 0.50 BRL.
39

Trabalho domiciliar feminino no Brasil: determinantes familiares e produtivos do trabalho remunerado exercido no próprio domicílio / Home-based work in Brazil: household and productive determinants for remunerated work at home

Martinez, Thiago Sevilhano 08 April 2008 (has links)
Esta pesquisa investiga os determinantes e a evolução recente no Brasil do trabalho remunerado feminino exercido no próprio domicílio ou simplesmente trabalho domiciliar. Quase 10% da população feminina ocupada, aproximadamente 4,5 milhões de mulheres, tem esse tipo de ocupação. Constatando a inexistência de estudos sobre o tema com dados quantitativos abrangentes, a presente pesquisa utiliza informações da Pesquisa Nacional por Amostras Domiciliares (PNAD) de 1992 a 2005 para analisar como evoluiu a proporção de trabalhadoras domiciliares no total da população ocupada. As mais importantes hipóteses delineadas na literatura a partir de estudos de caso são discutidas pela confrontação com os dados. Sob a ótica da demanda por essa forma de trabalho, analisa-se os setores que mais fazem uso do trabalho domiciliar feminino e as mudanças nessa composição, bem como sua relação com as transformações no mundo do trabalho decorrentes da reestruturação empresarial. Quanto à oferta por trabalho domiciliar, investiga-se como atributos individuais e familiares afetam as chances da mulher estar nesse tipo de condição de ocupação. É debatido como as transformações na inserção produtiva feminina afetaram a importância relativa do trabalho domiciliar. Constrói-se um modelo Logit Multinomial no Stata a partir dos dados da PNAD para comparar como mudou no tempo o impacto de cada atributo sobre a probabilidade de que uma mulher seja trabalhadora domiciliar. / This research investigates the determinants and recent developments of female home-based work in Brazil. Almost 10% of the occupied female population, approximately 4.5 million women, has this kind of occupation. Noting the lack of studies on the topic with comprehensive quantitative data, the present research uses information from PNAD beginning on 1992 until 2005 to evaluate how the proportion of female home-based workers on occupied population evolved. The most important assumptions outlined in the literature from case studies are discussed by confrontation with the data. From the perspective of demand for this type of work, sectors that intensively use female home-based work are analyzed, as well as its relationship with the changes in the labor market resulting from firms restructuring. On the supply of home-based work, it is investigated how individual and family attributes affect the chances of a woman to be in this work condition. It is discussed how the changes on female\'s productive insertion affected the relative importance of home-based work. A Multinomial Logit model is built on Stata using the data from PNAD to compare how the impacts of each attribute on the probability of a woman being home-based worker changed over time.
40

Modeling value of travel time to competitors by different ways logit models: what you win and lose that? / Modelando valor de tempo de viagem para modos concorrentes por diferentes modelos logit: o que se ganha e o que se perde?

Francisco Gildemir Ferreira da Silva 13 September 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Economists since 1965 search a way to measure the value of time. This paper addresses empirical results from a theoretical background proposed in the particular case of transport. The Tuong and Hensher (1985) paper unified the theory and empirical measurement however, over the years various methods for estimation of discrete choice models were not used to measure the values of travel time. This thesis measures the value of travel time of the intercity transport users in Cearà using four models: unstructured type McFadden and the other three, as proposed in Tuong and Hensher (1985a) (Becker, and DeSerpa and Tuong Hensher via Taylor expansion). Additional to the traditional logit model, it estimates the same models using the methodology developed by Morikawa (1989) and simulated maximum likelihood estimation and Bayesian to logit models like in Train (2003). The result indicates that it should use the estimation methods and different functional forms sparingly, because depending on the parameters obtained can be found values for travel time considerably different. On the other hand, the functional forms can be good for prediction. A choice of estimation methods such as enrichment suggests less distortion from standard model. A choice of functional form indicates the use the model of Becker or DeSerpa because of their small oscillation regardless of the estimation methods used. Already a combined choice of estimation method and functional form suggests Becker or DeSerpa with Simulated Maximum Likelihood estimation to obtain values of travel time and to forecasts. / Economistas desde 1965 debruÃam-se sobre uma forma de como mensurar o valor do tempo. O trabalho de Tuong e Hensher (1985) uniu teoria ao empirismo, entretanto, com o passar dos anos os mÃtodos diversos de estimaÃÃo por modelos de escolha discreta nÃo foram utilizados para a mediÃÃo do valor de tempo de viagem. Esta tese mensura o valor de tempo de viagem dos usuÃrios de transporte intermunicipal no Cearà utilizando de quatro modelos: nÃo estruturado tipo McFadden e os outros trÃs, conforme proposto em Tuong e Hensher (1985a), para Becker, DeSerpa e a proposta de Tuong e Hensher via expansÃo de Taylor. Adicional ao modelo logit tradicional, faz-se estimaÃÃes das mesmas formas funcionais utilizando da metodologia desenvolvida por Morikawa (1989) e depois a de estimaÃÃes de mÃxima verossimilhanÃa simulada e bayesiana para modelo logit com fatores aleatÃrios apresentada em Train (2003). O resultado indica que se devem utilizar os mÃtodos de estimaÃÃo e formas funcionais distintas com parcimÃnia, pois dependendo dos parÃmetros obtidos, podem ser encontrados valores para tempo de viagem consideravelmente diferente. Por outro lado, as formas funcionais podem ser boas para previsÃo tal como discutido acima. Uma escolha entre mÃtodos de estimaÃÃo sugere o enriquecimento como o que menos distorce as estimativas do logit padrÃo. Uma escolha de forma funcional indica o uso do modelo de Becker ou do DeSerpa por conta da sua pequena oscilaÃÃo independentemente dos mÃtodos de estimaÃÃo utilizados. Jà uma escolha combinada entre mÃtodo de estimaÃÃo e forma funcional sugere o modelo de Becker e DeSerpa com MÃxima VerossimilhanÃa Simulada, tanto para obter valores de tempo de viagem como para prever eventos.

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