Vol 14 No 4 (2014)
2014-09-01
Vol 14 No 4 (2014)
2014-09-01
Articles
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The Tel Aviv activity based model structure is similar to other activity based models described in the literature. The model run is supposed to converge to the equilibrium between generated tours and corresponding level of service (LOS) data. However, individual tour generation uses random draws for various choices (activity, time of day, destination, and mode). This introduces simulation errors, which combined with population sampling and limited precision of static traffic assignments, prevents the convergence of the model results. This paper analyses the above uncertainty sources on the basis of multiple model runs conducted for this study. Three averaging procedures are investigated and compared. Practical considerations regarding setting up the averaging procedures required for obtaining stable model results are discussed.
The Tel Aviv activity based model structure is similar to other activity based models described in the literature. The model run is supposed to converge to the equilibrium between generated tours and corresponding level of service (LOS) data. However, individual tour generation uses random draws for various choices (activity, time of day, destination, and mode). This introduces simulation errors, which combined with population sampling and limited precision of static traffic assignments, prevents the convergence of the model results. This paper analyses the above uncertainty sources on the basis of multiple model runs conducted for this study. Three averaging procedures are investigated and compared. Practical considerations regarding setting up the averaging procedures required for obtaining stable model results are discussed.
The Tel Aviv activity based model structure is similar to other activity based models described in the literature. The model run is supposed to converge to the equilibrium between generated tours and corresponding level of service (LOS) data. However, individual tour generation uses random...
Shlomo Bekhor, Leonid Kheifits, Michael Sorani -
The current study analyses the efficiency of choice set generation methods for bicycle routes and proposes the extension of cost functions to bicycle-oriented factors not limited to distance and time. Three choice set generation methods for route choice were examined in their ability to generate relevant and heterogeneous routes: doubly stochastic generation function, breadth first search on link elimination, and branch & bound algorithm. Efficiency of the methods was evaluated for a high-resolution network by comparing the performances with four multiattribute cost functions accounting for scenic routes, dedicated cycle lanes, and road type. Data consisted of 778 bicycle trips traced by GPS and carried out by 139 persons living in the Greater Copenhagen Area, in Denmark. Results suggest that both the breadth first search on link elimination and the doubly stochastic generation function generated realistic routes, while the former outperformed in computation cost and the latter produced more heterogeneous routes.
The current study analyses the efficiency of choice set generation methods for bicycle routes and proposes the extension of cost functions to bicycle-oriented factors not limited to distance and time. Three choice set generation methods for route choice were examined in their ability to generate relevant and heterogeneous routes: doubly stochastic generation function, breadth first search on link elimination, and branch & bound algorithm. Efficiency of the methods was evaluated for a high-resolution network by comparing the performances with four multiattribute cost functions accounting for scenic routes, dedicated cycle lanes, and road type. Data consisted of 778 bicycle trips traced by GPS and carried out by 139 persons living in the Greater Copenhagen Area, in Denmark. Results suggest that both the breadth first search on link elimination and the doubly stochastic generation function generated realistic routes, while the former outperformed in computation cost and the...
The current study analyses the efficiency of choice set generation methods for bicycle routes and proposes the extension of cost functions to bicycle-oriented factors not limited to distance and time. Three choice set generation methods for route choice were examined in their ability to...
Katrín Halldórsdóttir, Nadine Rieser-Schüssler, Kay W. Axhausen, Otto A. Nielsen, Carlo G. Prato -
Despite growing interest in the notion that respondents in stated choice surveys may make their decisions on the basis of only a subset of the presented attributes, the impact of any unimportant attributes on the estimates of other valuations is somewhat unclear. This paper presents evidence from a two stage survey where the second stage eliminates attributes deemed unimportant in the first stage. Our analysis shows no evidence of systematic differences between the results of the two stages. This leads to the conclusion that, up to a point where respondent burden may become an issue, analysts should include all attributes that may be relevant, and allow the respondent to filter out those that play no role.
Despite growing interest in the notion that respondents in stated choice surveys may make their decisions on the basis of only a subset of the presented attributes, the impact of any unimportant attributes on the estimates of other valuations is somewhat unclear. This paper presents evidence from a two stage survey where the second stage eliminates attributes deemed unimportant in the first stage. Our analysis shows no evidence of systematic differences between the results of the two stages. This leads to the conclusion that, up to a point where respondent burden may become an issue, analysts should include all attributes that may be relevant, and allow the respondent to filter out those that play no role.
Despite growing interest in the notion that respondents in stated choice surveys may make their decisions on the basis of only a subset of the presented attributes, the impact of any unimportant attributes on the estimates of other valuations is somewhat unclear. This paper presents evidence...
Stephane Hess -
Elasticities for freight transport in the context of mode choice are hardly available for markets in which intermodal container transport competes with truck only transport. These elasticities are expected to be different, however, from values found in the literature for traditional freight transport, as trucking is a complement to rail or inland waterway transport when used for pre- or post-haulage, but a substitute to these modes when used from the origin to the final destination. This paper presents direct and cross (generalized) cost elasticities for road and rail transport demand for continental intermodal container transport and constitutes an attempt to compare the elasticities for intermodal transport with those for general freight transport. We first look into the sensitivity of elasticities to the total length of the haul and to pre- and post-haulage distances by road using a stylized, theoretical model. The assumption about pre- and post-haulage distances in mode choice appears to be important, as elasticities for road transport in the context of intermodal transport chains can be half of the values currently used in a conventional mode choice situation without access or egress by road. Next we provide empirical values for the market of container transport using a European multimodal network model. The absolute values of the estimated elasticities follow a double trend when the cost for trucking is modified: they increase with the distance between the origin and the destination, but decrease with the length of pre- or post-haulage. In all cases, the values are estimated to be inelastic. Overall, the “complement” component of the computed elasticities for rail-road transport is estimated to be approximately 20% of the total impact.
Elasticities for freight transport in the context of mode choice are hardly available for markets in which intermodal container transport competes with truck only transport. These elasticities are expected to be different, however, from values found in the literature for traditional freight transport, as trucking is a complement to rail or inland waterway transport when used for pre- or post-haulage, but a substitute to these modes when used from the origin to the final destination. This paper presents direct and cross (generalized) cost elasticities for road and rail transport demand for continental intermodal container transport and constitutes an attempt to compare the elasticities for intermodal transport with those for general freight transport. We first look into the sensitivity of elasticities to the total length of the haul and to pre- and post-haulage distances by road using a stylized, theoretical model. The assumption about pre- and post-haulage distances in mode...
Elasticities for freight transport in the context of mode choice are hardly available for markets in which intermodal container transport competes with truck only transport. These elasticities are expected to be different, however, from values found in the literature for traditional freight...
Bart Jourquin, Lóránt Tavasszy, Liwei Duan -
The highly competitive market conditions in the passenger transportation industry pressure service provider firms to adopt an attitude of customer-oriented service quality. Even though the service quality of passenger transportation has been a concern in the literature, how the service quality of highway passenger transportation systems could be improved using a systematic approach has not been investigated. Using Quality Function Deployment (QFD), this is the first attempt to improve the quality of highway passenger transportation services. The analysis reveals that the passengers’ most important expectations are employees’ empathetic approach toward customers, technical specifications of buses, error-free services, and competent employees. Additionally, the most important technical requirements are employee-oriented technical requirements, technical specifications of buses, and error-free services in highway passenger transportation.
The highly competitive market conditions in the passenger transportation industry pressure service provider firms to adopt an attitude of customer-oriented service quality. Even though the service quality of passenger transportation has been a concern in the literature, how the service quality of highway passenger transportation systems could be improved using a systematic approach has not been investigated. Using Quality Function Deployment (QFD), this is the first attempt to improve the quality of highway passenger transportation services. The analysis reveals that the passengers’ most important expectations are employees’ empathetic approach toward customers, technical specifications of buses, error-free services, and competent employees. Additionally, the most important technical requirements are employee-oriented technical requirements, technical specifications of buses, and error-free services in highway passenger transportation.
The highly competitive market conditions in the passenger transportation industry pressure service provider firms to adopt an attitude of customer-oriented service quality. Even though the service quality of passenger transportation has been a concern in the literature, how the service quality...
Fatma Pakdil, Feride Bahar Kurtulmuşoğlu -
Changes in the roles of the government and the private sector in the provision of public services along with budget constraints are resulting in an increasing use of the concession approach for financing and managing roads. In the last few years, many of these contracts set up incentives linked to bonuses to encourage the concessionaire to render a better service to the users. Road safety is one the aspects on the basis of which concessionaires can be rewarded according to their performance. The goal of this paper is to evaluate whether road safety incentives are being defined in the right way nowadays in different European countries and also identify what incentives would need to be implemented to achieve a socially optimal road safety level. To that end, we develop a specific incentive for road concession contracts that encourages companies to achieve the optimal level. We apply this methodology to three case studies of concessions recently awarded in order to determine to what extend the incentives they set up are closer or farther to the optimum.
Changes in the roles of the government and the private sector in the provision of public services along with budget constraints are resulting in an increasing use of the concession approach for financing and managing roads. In the last few years, many of these contracts set up incentives linked to bonuses to encourage the concessionaire to render a better service to the users. Road safety is one the aspects on the basis of which concessionaires can be rewarded according to their performance. The goal of this paper is to evaluate whether road safety incentives are being defined in the right way nowadays in different European countries and also identify what incentives would need to be implemented to achieve a socially optimal road safety level. To that end, we develop a specific incentive for road concession contracts that encourages companies to achieve the optimal level. We apply this methodology to three case studies of concessions recently awarded in order to determine to what...
Changes in the roles of the government and the private sector in the provision of public services along with budget constraints are resulting in an increasing use of the concession approach for financing and managing roads. In the last few years, many of these contracts set up incentives...
Pablo Perez de Villar, Jose Manuel Vassallo -
The application of activity-based models of travel demand to planning practice has triggered interest in issues that potentially improve the accuracy and/or usefulness of model forecasts. The limited knowledge of uncertainty propagation in complex stochastic model systems has put uncertainty analysis high on the research agenda to differentiate between simulation error and policy effects. Focusing on transport mode choice, this paper draws attention to the use of model ensembles, which has hardly been explored in travel demand forecasting. Prior studies predicting transport mode choice has typically relied on a single equation, relating observed transport mode choices to a set of personal and contextual variables. The estimated single model is then assumed to apply to all individuals. This paper explores the idea of replacing a single equation/representation with an ensemble of model predictions, using the decision tree formalism. Potentially, ensembles better capture the notion that travellers may use different heuristics in their transport mode decisions. The aim of the study is to investigate whether the use of a model ensemble of different decision heuristics will reduce the error/uncertainty in predicting transport mode decisions. Results of the study, conducted in the Rotterdam region, The Netherlands, suggest that the accuracy of predicting transport mode choice is improved, albeit non-monotonically, with increasing ensemble size. Simultaneously, the uncertainty related to these predictions is decreasing. Finally, it is shown that the importance of the selected explanatory variables co-varies with ensemble size. Estimation results tend to become stable in this study with an ensemble size of approximately 20 decision trees.
The application of activity-based models of travel demand to planning practice has triggered interest in issues that potentially improve the accuracy and/or usefulness of model forecasts. The limited knowledge of uncertainty propagation in complex stochastic model systems has put uncertainty analysis high on the research agenda to differentiate between simulation error and policy effects. Focusing on transport mode choice, this paper draws attention to the use of model ensembles, which has hardly been explored in travel demand forecasting. Prior studies predicting transport mode choice has typically relied on a single equation, relating observed transport mode choices to a set of personal and contextual variables. The estimated single model is then assumed to apply to all individuals. This paper explores the idea of replacing a single equation/representation with an ensemble of model predictions, using the decision tree formalism. Potentially, ensembles better capture the notion...
The application of activity-based models of travel demand to planning practice has triggered interest in issues that potentially improve the accuracy and/or usefulness of model forecasts. The limited knowledge of uncertainty propagation in complex stochastic model systems has put uncertainty...
Soora Rasouli, Harry J.P. Timmermans -
A lot of research has been done on the adoption of electric vehicles and on the deployment of the infrastructure for charging the batteries of these vehicles. Currently the total number of installed charging points keeps growing due to both public and private investments. Often charging services are offered as free service extensions. Maintaining this free business model will be difficult on the long term because of the investments needed. Therefore, the long term business viability and durability is not always clear from an investor point of view. This work presents a techno-economic model that describes the expected cost and revenue evolution resulting from different deployment strategies for a municipal or private parking facility operator. For charging service providers, charging pole exploiters and infrastructure owners for electric vehicle charging, the model allows to project the expected profitability. The main findings from this research indicate that business cases for public charging infrastructure can be viable, durable and could be competitive with the costs for charging the electric vehicle at home. Also, in a multi-actor market model all actors involved could benefit from deploying electric vehicle charging infrastructure. Although the business cases will be positive, significant investments are needed.
A lot of research has been done on the adoption of electric vehicles and on the deployment of the infrastructure for charging the batteries of these vehicles. Currently the total number of installed charging points keeps growing due to both public and private investments. Often charging services are offered as free service extensions. Maintaining this free business model will be difficult on the long term because of the investments needed. Therefore, the long term business viability and durability is not always clear from an investor point of view. This work presents a techno-economic model that describes the expected cost and revenue evolution resulting from different deployment strategies for a municipal or private parking facility operator. For charging service providers, charging pole exploiters and infrastructure owners for electric vehicle charging, the model allows to project the expected profitability. The main findings from this research indicate that business cases for...
A lot of research has been done on the adoption of electric vehicles and on the deployment of the infrastructure for charging the batteries of these vehicles. Currently the total number of installed charging points keeps growing due to both public and private investments. Often charging...
Frederic Vannieuwenborg, Mathieu Tahon, Sofie Verbrugge, Didier Colle, Mario Pickavet, Piet Demeester -
This paper explores the factors influencing the pricing behaviour of full-service carriers in European hub-to-hub markets. Drawing on a 2009 dataset containing route and airfare information, we establish an econometric model to estimate the impact of route structure, alliances, and market concentration on the pricing of European full-service carriers in these markets. The results suggest that alliances on routes connecting two primary hubs, airport concentration, market share inequality and competition from low-cost carriers influence average airfares of full-service carriers in the European hub-to-hub markets.
This paper explores the factors influencing the pricing behaviour of full-service carriers in European hub-to-hub markets. Drawing on a 2009 dataset containing route and airfare information, we establish an econometric model to estimate the impact of route structure, alliances, and market concentration on the pricing of European full-service carriers in these markets. The results suggest that alliances on routes connecting two primary hubs, airport concentration, market share inequality and competition from low-cost carriers influence average airfares of full-service carriers in the European hub-to-hub markets.
This paper explores the factors influencing the pricing behaviour of full-service carriers in European hub-to-hub markets. Drawing on a 2009 dataset containing route and airfare information, we establish an econometric model to estimate the impact of route structure, alliances, and market...
Shengrun Zhang, Ben Derudder, Frank Witlox -
This paper is intended to set the context for policy discussion on HSR feasibility from the perspective of station accessibility. We compare the proposed Los Angeles – San Francisco HSR corridor to the functioning HSR line between Madrid and Barcelona to assess relative station accessibility based on urban structure. Our methodology assesses socioeconomic and spatial characteristics of mono-centric versus polycentric cities that may affect HSR accessibility. By addressing challenges of unit (urban geography), data series (normalization) and identifying four key components of HSR attractiveness (population, population density, income and employment) we have created a methodology that allows us to assess relative station accessibility in the four compared metropolitan areas. We find urban structure limits the potential accessibility of HSR in the California context, and warn HSR planners they should proceed with caution.
This paper is intended to set the context for policy discussion on HSR feasibility from the perspective of station accessibility. We compare the proposed Los Angeles – San Francisco HSR corridor to the functioning HSR line between Madrid and Barcelona to assess relative station accessibility based on urban structure. Our methodology assesses socioeconomic and spatial characteristics of mono-centric versus polycentric cities that may affect HSR accessibility. By addressing challenges of unit (urban geography), data series (normalization) and identifying four key components of HSR attractiveness (population, population density, income and employment) we have created a methodology that allows us to assess relative station accessibility in the four compared metropolitan areas. We find urban structure limits the potential accessibility of HSR in the California context, and warn HSR planners they should proceed with caution.
This paper is intended to set the context for policy discussion on HSR feasibility from the perspective of station accessibility. We compare the proposed Los Angeles – San Francisco HSR corridor to the functioning HSR line between Madrid and Barcelona to assess relative station accessibility...
Chuyuan Zhong, Germà Bel, Mildred E. Warner