• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 33
  • 31
  • 5
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 100
  • 100
  • 70
  • 21
  • 19
  • 18
  • 15
  • 14
  • 13
  • 12
  • 12
  • 12
  • 11
  • 11
  • 10
  • 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.
51

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

Thaís Mendonça Barcellos 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.
52

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

Thiago Sevilhano Martinez 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.
53

Prediktivní modelování v oblasti řízení kreditních rizik / Predictive Modeling in Credit Risk Management

Švastalová, Iva January 2012 (has links)
The diploma thesis is focused on predictive modeling in credit risk management. Banks and financial institutions are mainly interested in it to estimate the probability of client's default in order to make a decision about which client will be accepted and which client will be rejected. The theoretical part includes an introduction of credit scoring and a description of discrete choice models. The linear probability model, the probit model and the logit model are described in detail. The logit model is afterwards used for the prediction of client's default. The practical part is focused on a statistical description of the dataset and a description of how to work with it before we start with the development of the credit scoring model. After that follows the estimation of the model on testing sample, its testing and the estimation of the model on full sample with a description of individual steps of calculation and outputs of the program SPSS.
54

Akzeptanz variabler Strompreise – eine Stated Choice Befragung zu variablen Strompreisen für private Haushalte

Höhn, Karsten 19 December 2016 (has links) (PDF)
Das Ziel der Masterarbeit ist es zu klären, ob private Haushalte variable Strompreise akzeptieren und die Stärke der charakteristischen Merkmale zu ermitteln. Der dazu benötigte Datensatz wurde mit Hilfe einer Stated Choice Befragung im Internet ermittelt. Dafür wurden drei Gerätekategorien und ein Dreitarifmodell formuliert. Für die Auswertung wurde ein additiv verknüpftes Teilwert-Nutzenmodell und ein binäres Logit-Choice-Modell verwendet. Signifikante Variablen wurden über das Top-down-Verfahren bestimmt. Das Modell und die Schätzer der Preise wurden im Anschluss durch Hypothesentest getestet. Als signifikante Schätzer, mit stark negativen Werten, stellten sich in allen Kategorien die Preise heraus. Die Hypothesentests ergaben, dass es sinnvoll ist, die Schätzer der Preise für die ersten beiden Gerätetypen zusammenzufassen. Es stellte sich eine unterproportionale Preiselastizität der Nachfrage heraus und eine hohe Akzeptanz ein Teil der Geräte in den Nachtstunden zu nutzen. Insgesamt sprachen sich mehr Teilnehmer für ein Smart-Meter-Gateway aus als dagegen. / The aim of the master thesis is to clarify whether private households accept variable electricity prices and determine the strength of the characteristic attributes. The data set was determined with a Stated Choice survey on the Internet. For this purpose, three device categories and a three-tariff model were formulated. An additive-linked partial-value model and a binary logit choice model were used for the evaluation. Significant variables were determined by using the top-down method. Afterwards the model and the estimators of the prices were tested with statistical hypothesis testings. The price emerged as a significant estimator, with strongly negative values in all categories. The hypothesis tests showed that it is useful to conclude the estimators of the prices for the first two device types. The results showed an inelastic price elasticity of demand and a high acceptance of the subjects to use a part of the devices in the night hours. Overall, more participants decide to use a smart meter gateway than to refuse it.
55

Stochastic user equilibrium with a bounded choice model

Watling, David Paul, Rasmussen, Thomas Kjær, Prato, Carlo Giacomo, Nielsen, Otto Anker 21 December 2020 (has links)
Stochastic User Equilibrium (SUE) models allow the representation of the perceptual and preferential differences that exist when drivers compare alternative routes through a transportation network. However, as an effect of the used choice models, conventional applications of SUE are based on the assumption that all available routes have a positive probability of being chosen, however unattractive. In this paper, a novel choice model, the Bounded Choice Model (BCM), is presented along with network conditions for a corresponding Bounded SUE. The model integrates an exogenously-defined bound on the random utility of the set of paths that are used at equilibrium, within a Random Utility Theory (RUT) framework. The model predicts which routes are used and unused (the choice sets are equilibrated), while still ensuring that the distribution of flows on used routes accords to a Discrete Choice Model. Importantly, conditions to guarantee existence and uniqueness of the Bounded SUE are shown. Also, a corresponding solution algorithm is proposed and numerical results are reported by applying this to the Sioux Falls network.
56

Discriminación de género en el acceso al crédito en PYMES

Torres Arica, Marycielo Zarella 14 June 2020 (has links)
Hoy en día, las Pequeñas y Medianas Empresas (PYMES) son consideradas como una fuente de crecimiento, empleo e inclusión social; sin embargo, estas sufren de limitaciones recurrentes respecto al acceso al crédito sobre todo si son lideradas por mujeres. Por ello, la presente investigación tiene como objetivo determinar la existencia de discriminación de género en el acceso al crédito en PYMES en el Perú en el año 2017 mediante la Encuesta Nacional de Empresas 2018 (ENE) para lo cual se utilizara un modelo econométrico Probit y se analizaran variables como edad, educación del propietario, sector económico, etc., lo cual demuestra que la probabilidad de que una PYME logre acceder al crédito disminuye cuando este presenta como propietario una mujer y afirmando la hipótesis sobre si en realidad la estructura de la empresa varía dependiendo del sexo del propietario de la PYME teniendo énfasis en la educación del propietario y sector económico al cual la PYME pertenece. / Nowadays, Small and Medium Enterprises (SMEs) are considered a source of growth, employment, and social inclusion; however, they suffer from recurrent limitations in access to credit, especially if they are led by women. For that, reason, the aim of this research is to determine the existence of gender discrimination in access to credit in SMEs in Peru in 2017 through the National Survey of Companies 2018 (ENE). To do so, a Probit econometric model will be used and variables such as age, owner's education, economic sector, etc. will be analyzed, which shows that the probability of an SME gaining access to credit decreases when the owner is a woman and affirms the hypothesis that the structure of the business varies depending on the sex of the SME owner, with emphasis on the education of the owner and the economic sector to which the SME belongs. / Trabajo de investigación
57

Decision-support tool for identifying locations of shared mobility hubs : A case study in Amsterdam

Podestà, Pietro January 2022 (has links)
Shared mobility is considered a more sustainable alternative to private modes. Nonetheless, its sudden and sometimes “out of control” emergence poses issues that need to be addressed. Lack of regulations and public space mismanagement cause sidewalks and city roads to be overcrowded with shared vehicles (especially in the case of micromobility). This causes nuisance and safety concerns and hinders the societal benefits shared mobility may provide. Shared mobility hubs have the potential to address these issues. The research was carried out within the context of the SmartHubs project, an EIT Urban Mobility project initiated in 2021 by a diverse consortium of 7 cities, companies, and universities to develop and validate effective and economically viable mobility hub solutions. This degree project aims to improve the Decision-Support-Tool (DST) developed by SmartHubs to identify locations of shared-mobility hubs having high potential in driving sustainable travel usage. To achieve that, the thesis proposes a methodology for determining smart hub locations and their corresponding utilities based on the combination of GIS cluster analysis of free-floating shared mobility parking patterns and a stated-preference study. The potential hub locations were determined from the cluster analysis of free-floating trip characteristics. Using the stated preference survey data, the thesis develops a model to estimate the probability of parking at the hub as a function of explanatory variables, including walking distance, reward policies and the parking situation. The model testing results showed that the proposed methodology can well predict the hub (usage) demand and improve the current DST originally developed in the SmartHubs project.
58

Data augmentation for latent variables in marketing

Kao, Ling-Jing 13 September 2006 (has links)
No description available.
59

Essays on consumer behaviour and pricing

Mahmood, Ammara January 2014 (has links)
This dissertation is a collection of five essays examining different aspects of consumer and firm behavior in dynamic markets. The first essay combines clickstreams of users at a major news website with Facebook activity data, to study if social networks complement or compete for online browsing time. This is the first empirical study to show that Facebook activity increases time spent on news sites. Online news consumption is a shared experience, as the activity of social network friends strongly influences the behavior of other network members. We also find that visitors’ own browsing patterns are important predictors of online content consumption. The second essay examines consumer attitudes to risk and uncertainty vis-a-vis their purchase and search decisions for air tickets online. Using a two-stage model of purchase incidence and carrier choice, we find that browsing experience, search costs and product characteristics are important predictors of purchase incidence. Implications for website managers are also discussed. The third essay provides insights on the impact of customer heterogeneity and preference stochasticity on behavior based price discrimination. While customer heterogeneity intensifies competition, resulting in greater price discrimination, preference stochasticity reduces the incidence of price discrimination. Overall, the effect of preference stochasticity is more salient. The fourth essay presents models of strategic interaction to analyze the impact of dominance and concentration on pricing strategies. We show that lack of market dominance is a sufficient condition for discounts to existing customers. We further test our predictions via an experiment with pricing professionals. The behavior of professionals confirms that price discrimination increases with market dominance and concentration; however, lack of dominance is not a sufficient condition for loyalty discounts. We contend that increasing competition is a more effective means of improving consumer welfare compared to regulating dominant firms. The fifth essay considers the role of identity and customer type recognition in influencing pricing behavior in dynamic markets with symmetric and asymmetric players. When customer identity is detectable firms charge higher prices to repeat customers while new customers are offered lower prices. However, pricing behavior changes when information on customer type is available and this behavior varies with market structure. Age, education and experience of managers are also found to significantly influence pricing behavior.
60

Explorando técnicas para a localização e identificação de potenciais usuários de transporte público urbano / Exploring techniques for the location and identification of potential users of urban public transportation

Alves, Victor Frazão Barreto 10 May 2011 (has links)
Um dos objetivos dos projetos e estudos na área de transporte público é atrair o maior número possível de viagens. Um primeiro passo para estimular uma maior utilização do transporte público pode ser a captação de pessoas que já têm predisposição para utilizá-lo, mas que não o fazem por alguma deficiência específica no serviço. Este é o contexto no qual mapas que representam o potencial de utilização dos transportes públicos podem desempenhar um papel importante, como discutido neste estudo. A pesquisa tem como objetivo principal a aplicação e avaliação de duas técnicas destinadas a identificar potenciais usuários de transporte público e como estes se distribuem geograficamente em uma cidade brasileira selecionada para o estudo. Nas técnicas aqui exploradas, o município em análise é dividido em áreas em função do código de endereçamento postal. Estas áreas são caracterizadas pelos atributos socioeconômicos da sua população e do sistema de transporte. Diante da hipótese de melhoria na qualidade do transporte público, dois segmentos de usuários de automóvel foram determinados: usuários que trocariam para ônibus e usuários que ainda preferem o carro. Com isso, foi construído um modelo capaz de representar o comportamento de escolha dos usuários de cada área. A metodologia proposta envolve quatro passos: i) comparação de modelos Logit elaborados com dados de São Carlos (Brasil) e Wageningen (Holanda), ii) ajustes no modelo de São Carlos, iii) elaboração de um modelo de escolha modal por redes neurais artificiais e iv) elaboração dos mapas potenciais. As duas últimas etapas foram concebidas tanto para análises independentes, como também para comparação com o modelo Logit. Assim, a construção de cenários futuros permitiu identificar e localizar espacialmente os potenciais usuários de transporte público. Foi possível verificar também qual a influência de alguns atributos sobre a escolha do modo de transporte urbano. Por exemplo, usuários de domicílios com três ou quatro pessoas têm menor probabilidade de vir a utilizar o ônibus regularmente. Por fim, um cenário futuro tornou possível destacar áreas onde é esperado um aumento do potencial de uso do transporte público devido a mudanças nos valores de densidade populacional. / One of the objectives of projects and studies on public transport is to attract the largest possible number of trips. A first step for increasing transit ridership may be the attraction of those individuals who already have a predisposition to use the service, but do not use it because of any specific inadequacies. This is the context in which maps displaying the potential use of public transport may play an important role, as discussed in this study. The research aims at the application and evaluation of two techniques used to identify potential users of public transport and to show how they are geographically distributed in a Brazilian city selected for the study. In the techniques discussed here, the municipality under analysis is divided into areas according to the postal codes of the streets. These areas are characterized by socioeconomic attributes of the population and of the transport system. Two segments of automobile users were determined, under the assumption that the quality of public transport would be improved: users who would switch to buses and users who still prefer the car. Based on that, a model designed to represent the choice behavior of users in each urban area was built. The proposed methodology involved four steps: i) the comparison of Logit models built with data of São Carlos (Brazil) and Wageningen (The Netherlands), ii) adjustments in the model of São Carlos, iii) the development of a mode choice model based on artificial neural networks, and iv) construction of potential maps. The third and fourth steps were meant for both independent analysis, and also for comparison with the Logit model. Thus, the construction of future scenarios allowed the identification and spatial location of potential users of public transport. It was also possible to learn about the influence of some attributes on urban transportation choice. For example, users living in households with three or four persons are less likely to become bus riders. Finally, a future scenario was able to highlight the areas where the potential for public transport could be increased due to changes in population density values.

Page generated in 0.0651 seconds