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Modeling the Effect of New Commuter Bus Service on Demand and the Impact on GHG Emissions: Application to Greater BostonLyman, Christopher 02 July 2019 (has links)
The transportation sector is considered one of the major contributors to greenhouse gas (GHG) emissions in metropolitan areas, and any efforts to reduce these emissions requires strategic management of multiple transportation modes. This paper presents a method to identify opportunities to reduce GHG emissions by expanding commuter bus services and incentives to shift commuters from private cars to transit. The approach uses a nested multinomial logit model for mode choice in a region that includes driving alone, carpooling, walking, cycling, and using four possible transit modes (ferry, commuter rail, rapid transit and bus) by walk access or driving access. A model of existing conditions was calibrated with data from the Boston metropolitan area. Using an emission factor model based on average speeds from the California Air Resources Board (CARB), the net effect of new commuter bus service on GHG emissions from transportation was estimated. Potential GHG reductions are weighed against the capital and operating costs of new transit services to quantify the cost-effectiveness of a new commuter bus service for isolated origin-destination pairs. This modeling framework is used to optimize fares and bus frequency in order to identify the corridors with the most cost-effective potential for GHG reduction. Results are presented for the Boston region, demonstrating the feasibility of implementation and the potential magnitude of benefits for cost-effectively reducing GHG emissions associated with transportation. The method is general and can be applied in other cities around the world.
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Mixed Multinomial Logit Analysis of Bicyclist Injury-severity in Single Motor Vehicle Crashes Based on Intersection and Non Intersection LocationsMoore, Darren N. 05 October 2009 (has links)
No description available.
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Evaluating The Impact Of Oocea's Dynamic Message Signs (dms) On Travelers' Experience Using Multinomial And Ordered Logit For The Post-deployment SurveyLochrane, Taylor 01 January 2009 (has links)
The purpose of this thesis was to evaluate the impact of dynamic message signs (DMS) on the Orlando-Orange County Expressway Authority (OOCEA) toll road network using the Post-Deployment DMS Survey analysis. DMS are electronic traffic signs used on roadways to give travelers information about travel times, traffic congestion, accidents, disabled vehicles, AMBER alerts, and special events. The particular DMS referred to in this study are large rectangular signs installed over the travel lanes and these are not the portable trailer mount signs. The OOCEA has added twenty-nine fixed DMS to their toll road network from 2006-2008. At the time of the post-deployment survey, a total of twenty-nine DMS were up and running on the OOCEA toll road network. Since most of the travelers on the OOCEA toll roads were from Orange, Osceola, and Seminole counties, this study was limited to these counties. This thesis documents the results for the post-deployment survey analysis. The instrument used to analyze the travelers' perception of DMS was a survey that utilized computer aided telephone interview. The post-deployment survey was conducted during the month of May, 2008. Questions pertaining to the acknowledgement of DMS on the OOCEA toll roads, satisfaction with travel information provided on the network, formatting of the messages, satisfaction with different types of messages, diversion questions (Revealed and Stated preferences), and classification/socioeconomic questions (such as age, education, most traveled toll road, county of residence, and length of residency) were asked to the respondents. This thesis is using results of the multinomial logit model for diversion of traffic. This model takes into account the different diversion decisions from the post development survey (stay vs. divert all the way vs. divert and come back vs. abandon trip) and explains the differences in the diversion behavior. Drivers that use SunPass or Epass tend to stay on the toll road during unexpected congestion. Frequent SR 408 users are more likely to divert and stay off the toll road and frequent SR 417 users are more likely to divert and get back on the toll road. Drivers whose stated preference was to divert off the toll road were more likely to do the same in the real world. However, not too many of the respondents were likely to abandon their trips in the real world even if they said they would in a hypothetical congestion scenario. Users of 511 were more likely to divert and get back on the toll road or abandon their trips due to unexpected congestion. OOCEA can use this study to concentrate on keeping their toll roads more attractive during unexpected congestion to keep drivers from diverting all the way or abandoning their trips. For example, better incident management in clearing accidents more efficiently (thereby decreasing delay) and encouraging the use of SunPass or EPass could help drivers stay than divert or abandon their trip. This thesis also used ordered logit model for satisfaction. This model explains the levels of magnitude of satisfaction with traveler information on OOCEA toll roads. Drivers who acquired traveler information from DMS were less likely to be dissatisfied with traveler information provided on toll roads than other respondents. Drivers who were satisfied with accuracy and information on hazard warnings on DMS were more likely to be satisfied with information provided on toll roads than other respondents. This thesis provides a microscopic insight on the driver behavior on toll roads. This thesis expands the diversion and satisfaction models from previous studies in a way that OOCEA can identify specific groups of drivers related to a given response behavior (i.e., diverts off toll roads or dissatisfied with traveler information). Such analysis can be conducted in the future in the same study area or replicated in other areas to quantify the effects of individual and choice related attributes on choice behavior.
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The Economics of Smallholder Households in Central HaitiKennedy, Nathan S. 14 May 2015 (has links)
Smallholder households in Haiti face many natural resource management challenges. Agricultural production occurs on deforested hillsides prone to erosion. Charcoal is in an important source of income, and woodfuel stocks are often over-exploited. Donor-funded projects and non- governmental organizations have made large investments in programs that promote soil conservation practices and reforestation. Despite the magnitude of the problems and the amount invested, there are relatively few economic analyses of the long-term adoption of soil conservation practices and woodfuel management. This dissertation uses an economics approach to examine the adoption of conservation practices and the management of woodfuel resources in Central Haiti using cross-sectional data covering 600 households. The results show that plot and household characteristics have different effects on adoption across different classes of soil practices, particularly with regard to perceived soil quality, market access, and household health status. The results also provide evidence of the management of charcoal woodfuel stocks on private land. These findings inform the design and targeting of new programs related to soil conservation and reforestation in Haiti and other developing countries. / Ph. D.
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應用個體選擇模式檢驗促銷活動之成效余思瑩 Unknown Date (has links)
個體選擇模式(discrete choice model)廣泛應用於國外的交通運輸及行銷領域,而國內交通運輸領域,也長期以此模式分析個體的運具選擇行為。反觀國內的行銷領域,因較難取得消費者的商品品牌購買紀錄,而鮮少應用個體選擇模式分析消費者的選擇行為。有鑒於此,本研究嘗試以問卷收集消費者對三個洗髮精品牌的選擇行為,以個體選擇模式中的多項邏輯模式(multinomial logit model)、巢狀邏輯模式(nested multinomial logit model)、混合多項邏輯模式(mixed logit model)進行分析,檢驗問卷設計中的促銷活動、消費者特性對選擇行為的影響性。
實證分析的結果發現,洗髮精的原價格及促銷折扣、贈品容量、加量不加價等促銷活動,皆對消費者的選擇行為有顯著的影響力,其中促銷折扣與贈品容量影響的程度較大,是較具有效果的促銷活動。而消費者的性別、年齡、職業及品牌更換的頻率,皆影響洗髮精的選擇行為。此外,消費者若固定選擇自己最常購買的洗髮精,此類型的消費者與其他人的品牌選擇行為,也有顯著的不同。
此外,根據本研究樣本,我們也發現海倫仙度絲與潘婷間的替代、互補性較強。 / Discrete choice model has been demonstrated to be a useful tool for analyzing consumers’ choice behavior data in the area of transportation and marketing research. However, since a complete data set containing consumers’ history of purchase behavior was rarely available to public, the model was less popular in the marketing research area than in the transportation research in Taiwan.
Based on limited survey data on consumers’ choice among three different brands of shampoo, we applied multinomial logit model、nested multinomial logit model、mixed logit model in this study to understand promotion program’s effect on consumers’ choice behavior , the result showed that shampoos’ original price、discount、volume of hair conditioner bestowal、more volume with the same price all had significant impacts on consumers’ choice behavior, among them, discount and volume of hair conditioner bestowel influenced more .In addition, consumers’ gender、age、occupation and frequency of changing brands also affected consumers on choosing brands of shampoos. The study also found that a consumer who chose the same brand regularly behaved notably differently.
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Consumer Willingness-to-Pay for Sustainability Attributes in Beer: A Choice Experiment Using Eco-LabelsAaron J Staples (6949067) 16 August 2019 (has links)
<p>Commercial and regional
brewers are increasingly investing in sustainability equipment that reduces
input use, operating costs, and environmental impact. These technologies often
require significant upfront costs that can limit market access to
microbreweries. One potential solution for these brewers is to market their
product as sustainable and charge a premium for their product to offset some of
the costs. A stated preference choice experiment of a nationally-representative
sample is undertaken to elicit consumer willingness-to-pay (WTP) for
sustainability attributes in beer, thus determining whether a market for
sustainably-made beer exists. The facets of sustainability, including water
reduction, energy reduction, and landfill diversion, are portrayed through
eco-labels affixed the front of the primary packaging (aluminum can or glass
bottle). Multiple specifications are employed to handle model shortcomings and
incorporate discrete heterogeneity. Across all model specifications, <a>consumers
show a positive and statistically significant marginal WTP for landfill diversion
practices and carbon reduction practices, ranging from $0.40 to $1.37 per
six-pack and $0.67 to $1.21 per six-pack, respectively. </a>These results indicate consumers do in fact
place value on beer produced using sustainable practices, and the demographics
of consumers with the greatest WTP are similar to that of craft beer consumer.</p>
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Livelihood Strategies and Employment Structure in Northwest Pakistan / Existenzgrundlagenstrategien und Beschäftigungsstruktur in Nordwest PakistanKhan, Mohammad Asif 23 January 2008 (has links)
No description available.
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Factors Influencing Mode Choice For Intercity Travel From Northern New England To Major Northeastern CitiesNeely, Sean Patrick 01 January 2016 (has links)
Long-distance and intercity travel generally make up a small portion of the total number of trips taken by an individual, while representing a large portion of aggregate distance traveled on the transportation system. While some research exists on intercity travel behavior between large metropolitan centers, this thesis addresses a need for more research on travel behavior between non-metropolitan areas and large metropolitan centers. This research specifically considers travel from home locations in northern New England, going to Boston, New York City, Philadelphia, and Washington, DC. These trips are important for quality of life, multimodal planning, and rural economies. This research identifies and quantifies factors that influence people's mode choice (automobile, intercity bus, passenger rail, or commercial air travel) for these trips.
The research uses survey questionnaire data, latent factor analysis, and discrete choice modeling methods. Factors include sociodemographic, built environment, latent attitudes, and trip characteristics. The survey, designed by the University of Vermont Transportation Research Center and the New England Transportation Institute, was conducted by Resource Systems Group, Inc. in 2014, with an initial sample size of 2560. Factor analysis was used to prepare 6 latent attitudinal factors, based on 70 attitudinal responses from the survey statements. The survey data were augmented with built environment variables using geographic information systems (GIS) analysis. A set of multinomial logit models, and a set of nested logit models, were estimated for business and non-business trip mode choice.
Results indicate that for this type of travel, factors influencing mode choice for both business and non-business trips include trip distance; land use; personal use of technology; and latent attitudes about auto dependence, preference for automobile, and comfort with personal space and safety on public transportation. Gender is a less significant factor. Age is only significant for non-business trips.
The results reinforce the importance and viability of modeling long-distance travel from less populated regions to large metropolitan areas, and the significant roles of trip distance, built environment, personal attitudes, and sociodemographic factors in how people choose to make these trips for different purposes. Future research should continue to improve these types of long-distance mode choice models by incorporating mode specific travel time and cost, developing more specific attitudinal statements to expand latent factor analysis, and further exploring built environment variables. Improving these models will promote better planning, engineering, operations, and infrastructure investment decisions in many regions and communities across the United States which have not yet been well studied, possibly impacting levels of service.
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Prevalência de fatores associados à ocorrência de acidentes viários no entorno de pontos de parada em corredores de ônibusMachado, Rafaela César January 2017 (has links)
Com o crescimento da população em áreas urbanas, o transporte coletivo assume um importante papel nos deslocamentos diários nas cidades brasileiras. No entanto, o grande volume de pessoas no entorno desses sistemas podem resultar em pontos críticos de segurança viária. Recentemente, as pesquisas sobre melhorias na segurança viária estão se direcionando para a investigação da relação entre o ambiente construído - isto é, padrões de uso do solo; desenho urbano; e sistemas de transporte - e acidentalidade. Porém, a relação entre os sistemas de transporte coletivo por ônibus e o ambiente construído ainda é pouco explorada. O ponto mais crítico em segurança identificado na literatura em sistemas de transporte coletivo são as estações de embarque e desembarque. Assim, esta dissertação tem como objetivo verificar a existência de relação entre elementos do ambiente construído com a ocorrência e severidade de acidentes viários no entorno de pontos de parada em sistemas prioritários para ônibus. Para isso, aplicou-se os modelos de regressão Binomial Negativo (NB), na análise de frequência de acidentes, e os modelos Logit Ordenado (OL) e Logit Multinomial (MNL), para a análise de severidade. No modelo de frequência de acidentes totais, identificou-se duas variáveis significativas e, no modelo estimado para atropelamentos, três variáveis. O modelo de severidade resultou em 19 variáveis significativas para acidentes totais e oito variáveis significativas para atropelamentos. As variáveis referentes ao envolvimento de motocicletas, automóveis, presença de interseção e uso diversificado do solo foram as mais recorrentes. O estudo possibilitou também avaliar as diferenças e vantagens entre os modelos ordenados e os não-ordenados. O modelo Logit Multinomial teve ajustes levemente melhores do que o Logit Ordenado. Ressalta-se, entretanto, que o ajuste do modelo não deve ser o único critério a se considerar na escolha de modelos para o estudo de severidade de acidentes. / Public transport has played an important role in daily commutes in Brazilian cities as population grows in urban areas. However, high volumes of pedestrians near those systems may result in critical safety issues. Recent studies on road safety improvements have sought for evidence on the relationship between built environment - land use patterns; urban design; and transportation systems - and traffic safety. Nevertheless, the relationship between traffic safety at bus priority systems and the built environment is still incipient. According to studies, the most critical safety issues related to public transport are the stations for boarding and alighting. Thus, this thesis aims to verify the relationship between built environment and incidence and severity of traffic crashes in the surroundings of bus priority systems. To do so, we applied Negative Binomial regression models (NB) for the frequency analysis, and the Ordered Logit (OL) and Multinomial Logit (MNL) models for severity analysis. NB models resulted in two significant variables for traffic crashes in general and three variables for pedestrian crashes. The severity model resulted in 19 significant variables overall crashes and eight significant variables for pedestrian crashes. Variables related to the involvement of motorcycles, automobiles, intersections and mixed land use were significant in majority of model estimations. The results allowed to evaluate the goodness of fit between ordered and unordered models. MNL had a slightly better adjustments compared to OL. Goodness of fit, however, should not be the only criterion for selecting a model to assess crash severity.
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Prevalência de fatores associados à ocorrência e severidade de acidentes com bicicleta em Porto AlegreSilva, André Luiz Dultra Nascimento da January 2018 (has links)
Após o fim da Segunda Guerra Mundial, teve início um processo de aumento da utilização dos automóveis nos grandes centros urbanos que modificou o desenho das cidades e o padrão de deslocamento nesses espaços. Uma das diversas consequências negativas da consolidação do automóvel como principal meio de transporte nas metrópoles foi o aumento do número de acidentes no trânsito, principalmente os que envolviam os usuários de transporte ativo – pedestres e ciclistas. A promoção dos modos de transporte não motorizados, como a bicicleta, é tida como ação complementar para reversão desse processo, porém, para tanto, é necessário melhorar a percepção de segurança sobre o modo cicloviário. A tomada de decisão por parte dos gestores do tráfego acerca das intervenções viárias que melhoram a segurança dos ciclistas carece de entendimento sobre os elementos que influenciam a ocorrência de acidentes envolvendo estes usuários. Desse modo, o trabalho desenvolvido nesta dissertação tem como objetivo a verificação da existência de relação entre os elementos urbanos construídos, os fatores socioeconômicos e outras possíveis fontes de risco com a frequência e severidade dos acidentes cicloviários na cidade de Porto Alegre O processo de investigação utilizou softwares de georreferenciamento para consolidar os dados coletados segundo as unidades de análise definidas. A frequência de acidentes foi modelada através de Modelo de Regressão Binomial Negativo e a severidade de acidentes foi modelada através de Modelo Logit Multinomial. O modelo de frequência de acidentes apresentou duas variáveis significativas. Em seguida, foi gerado um novo modelo de frequência de acidentes a partir da eliminação de possíveis fontes de discrepância dos dados. Os resultados indicaram que este segundo modelo estava melhor ajustado ao cenário estudado. O modelo de severidade de acidentes foi composto por 18 variáveis significativas. Por fim, os elementos que demonstraram maior prevalência sobre a acidentalidade de ciclistas foram a interação com automóveis, a presença de vias arteriais, a proximidade com áreas de interseção e o envolvimento de usuários vulneráveis (jovens e idosos em bicicletas) nos acidentes. / After the end of the World War II, many cities around the world have experienced an increase on car using which changed the way cities were planned and also mobility patterns. That process has generated some problems at urban areas like road accidents increasing, most of them related to active transport modes - pedestrians and cyclers. Non motorized transportation modes fomentation, for example cycling, emerges as an alternative to change this issue. However, before it happens, cyclers need to feel more safe on transit. Understanding the influence of the elements that affect cyclers's safety gives to decision makers and traffic managers a better possibility to make the right decisions on safety improvement. Thus, this thesis aims to verify the relationship between built environment, socialeconomic factors and other risk sources and frequency and severity of traffic crashes involving cyclists in Porto Alegre. By using GIS softwares, the collected data were consolidated according to the defined analysis units. Accident’s frequencies were modeled and the coefficients were estimated by using Negative Binomial Regression Model and the severity of accidents was modeled as a Multinomial Logit Model. The accident frequency model counted with two sginificant variables. Then, a new accident frequency model was estimated from the elimination of possible sources of data discrepancy. Results have shown that the second model fit better on the studied scenario. The accident severity model resulted in 18 significant variables. Finally, the elements that showed highest prevalences on cyclists safety were car interaction, presence of arterial roads, proximity to intersection areas and vulnerable cyclists users (young and old ones cycling) involvement on accidents.
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