Pub Date : 2021-09-29DOI: 10.18757/EJTIR.2021.21.3.3982
Mauro Capurso, S. Hess, T. Dekker
Consideration of alternatives, as many other aspects related to the decision-making process, is not observable and challenging to measure. Even when supplementary information is collected during stated choice experiments, its use as an additional explanatory variable is discouraged due to potential endogeneity issues, measurement error and limited suitability for forecasting. To overcome these limitations, we propose an Integrated Choice and Latent Variable model where consideration of an alternative is treated as a latent variable. The novelty of the presented model is that the latent variable for consideration of an alternative itself is a function of another set of latent variables that represent thresholds applied by the decision maker to individual attributes (such as travel time and cost). The proposed hierarchical relationship between latent thresholds and latent consideration enables us to explain a share of otherwise purely random heterogeneity, and identify the structural drivers of consideration. The latter is of interest to policymakers and private operators.
{"title":"Stated consideration and attribute thresholds in mode choice models: a hierarchical ICLV approach","authors":"Mauro Capurso, S. Hess, T. Dekker","doi":"10.18757/EJTIR.2021.21.3.3982","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.3.3982","url":null,"abstract":"Consideration of alternatives, as many other aspects related to the decision-making process, is not observable and challenging to measure. Even when supplementary information is collected during stated choice experiments, its use as an additional explanatory variable is discouraged due to potential endogeneity issues, measurement error and limited suitability for forecasting. To overcome these limitations, we propose an Integrated Choice and Latent Variable model where consideration of an alternative is treated as a latent variable. The novelty of the presented model is that the latent variable for consideration of an alternative itself is a function of another set of latent variables that represent thresholds applied by the decision maker to individual attributes (such as travel time and cost). The proposed hierarchical relationship between latent thresholds and latent consideration enables us to explain a share of otherwise purely random heterogeneity, and identify the structural drivers of consideration. The latter is of interest to policymakers and private operators.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42385368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-19DOI: 10.18757/ejtir.2021.21.3.5467
Lisa Ecke, Miriam Magdolen, Bastian Chlond, P. Vortisch
Being a vast external influence, the COVID-19 pandemic causes major changes in travel behavior on the individual level. This exceptional situation and the political measures such as the lockdown lead to decreased overall travel demand and shifts in mode choice. To understand these effects, the analysis of car usage in private households offers explanatory insights. To this aim, this study provides a differentiation of car usage before and during the COVID -19 pandemic in spring 2020. Furthermore, insights into structural changes of car usage in private households based on German Mobility Panel data are presented. The results show that during the COVID -19 pandemic car usage was affected, and overall mileage decreased. Especially newer cars with large cubic capacity show a large decrease in mileage by 39 % between 2019 and 2020. In addition, we see that the type of car usage (business/private) and the household characteristics are related to different magnitudes of change in car usage. Overall, it becomes evident that examining identical households and cars before and during the pandemic allows for a deeper understanding of the impacts of the COVID -19 pandemic.
{"title":"Tracing the Effects of the Covid-19 Pandemic on Car Usage in Germany - an Analysis of the German Mobility Panel","authors":"Lisa Ecke, Miriam Magdolen, Bastian Chlond, P. Vortisch","doi":"10.18757/ejtir.2021.21.3.5467","DOIUrl":"https://doi.org/10.18757/ejtir.2021.21.3.5467","url":null,"abstract":"Being a vast external influence, the COVID-19 pandemic causes major changes in travel behavior on the individual level. This exceptional situation and the political measures such as the lockdown lead to decreased overall travel demand and shifts in mode choice. To understand these effects, the analysis of car usage in private households offers explanatory insights. To this aim, this study provides a differentiation of car usage before and during the COVID -19 pandemic in spring 2020. Furthermore, insights into structural changes of car usage in private households based on German Mobility Panel data are presented. The results show that during the COVID -19 pandemic car usage was affected, and overall mileage decreased. Especially newer cars with large cubic capacity show a large decrease in mileage by 39 % between 2019 and 2020. In addition, we see that the type of car usage (business/private) and the household characteristics are related to different magnitudes of change in car usage. Overall, it becomes evident that examining identical households and cars before and during the pandemic allows for a deeper understanding of the impacts of the COVID -19 pandemic.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41772875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-19DOI: 10.18757/EJTIR.2021.21.3.5515
Shoshanna Saxe, M. Dean, Shivani Raghav, Daniel Durrant, Matti Siemiatycki
This paper explores the timelines of large transportation infrastructure delivery, from first proposal to construction and opening in London, UK and Toronto, Canada. The goal of the paper is to identify both how long it takes projects to go from idea to delivery, the relative time of different stages in the delivery process, and if projects with long timelines see physical or technological changes in their design. This work contributes to two ongoing discussions around the speed of infrastructure delivery, one that argues infrastructure moves too slowly and major efforts are needed to speed delivery and another that argues that good infrastructure thinking requires time to breathe and care should be taken in rushing through the delivery process. Detailed delivery timelines from initial proposal to construction or operation are developed for 26 transportation projects (16 in Toronto and 10 in London) between the years 2000 and 2018. For each project the timelines of inception, approval, planning, procurement, environmental assessment, construction and operational phases are identified and compared. Long informal gestation periods are identified for many projects, particularly for linear projects. In many instances the informal gestation period dwarfs the time projects spent in formal planning. This research highlights the need to expand the conception of timeliness of infrastructure delivery to include the lengthy periods of informal debate and planning that can span years and build up community expectations about the imminence of a project, even before it has received formal assessment or approval. Detailed delivery timelines from initial proposal to construction or operation are developed for 26 transportation projects (16 in Toronto and 10 in London) between the years 2000 and 2018. For each project the timelines of inception, approval, planning, procurement, environmental assessment, construction and operational phases are identified and compared. Long informal gestational periods are identified for many projects, particularly for linear projects. In many instances the informal gestation period dwarfs the time projects spent in formal planning. This research highlights the need to expand the conception of timeliness of infrastructure delivery to include the lengthy periods of informal debate and planning that can span years and build up community expectations about the imminence of a project, even before it has received formal assessment or approval.
{"title":"Timelines of Transportation Infrastructure Delivery 2000 to 2018 in Toronto, Canada and London, UK","authors":"Shoshanna Saxe, M. Dean, Shivani Raghav, Daniel Durrant, Matti Siemiatycki","doi":"10.18757/EJTIR.2021.21.3.5515","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.3.5515","url":null,"abstract":"This paper explores the timelines of large transportation infrastructure delivery, from first proposal to construction and opening in London, UK and Toronto, Canada. The goal of the paper is to identify both how long it takes projects to go from idea to delivery, the relative time of different stages in the delivery process, and if projects with long timelines see physical or technological changes in their design. This work contributes to two ongoing discussions around the speed of infrastructure delivery, one that argues infrastructure moves too slowly and major efforts are needed to speed delivery and another that argues that good infrastructure thinking requires time to breathe and care should be taken in rushing through the delivery process. Detailed delivery timelines from initial proposal to construction or operation are developed for 26 transportation projects (16 in Toronto and 10 in London) between the years 2000 and 2018. For each project the timelines of inception, approval, planning, procurement, environmental assessment, construction and operational phases are identified and compared. Long informal gestation periods are identified for many projects, particularly for linear projects. In many instances the informal gestation period dwarfs the time projects spent in formal planning. This research highlights the need to expand the conception of timeliness of infrastructure delivery to include the lengthy periods of informal debate and planning that can span years and build up community expectations about the imminence of a project, even before it has received formal assessment or approval. Detailed delivery timelines from initial proposal to construction or operation are developed for 26 transportation projects (16 in Toronto and 10 in London) between the years 2000 and 2018. For each project the timelines of inception, approval, planning, procurement, environmental assessment, construction and operational phases are identified and compared. Long informal gestational periods are identified for many projects, particularly for linear projects. In many instances the informal gestation period dwarfs the time projects spent in formal planning. This research highlights the need to expand the conception of timeliness of infrastructure delivery to include the lengthy periods of informal debate and planning that can span years and build up community expectations about the imminence of a project, even before it has received formal assessment or approval. ","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42972960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-19DOI: 10.18757/EJTIR.2021.21.3.3949
Thomas O. Hancock, S. Hess
Latent class models have long been a tool for capturing heterogeneity across decisionmakers in the sensitivities to individual attributes. More recently, there has been increased interest in using these models to capture heterogeneity in actual behavioural processes, such as information/attribute processing and decision rules. This often leads to substantial improvement in model fit and the apparent finding of large clusters of individuals making choices in ways that are substantially different from those used by others. Such findings have however not been without criticism given the potential risk of confounding with other more modelspecific heterogeneity. In this paper, we consider an alternative approach for exploring the issue by contrasting the findings obtained with model averaging, which combines the results from a number of separately (rather than simultaneously) estimated models. We demonstrate that model averaging can accurately recover the different data generation processes used to create a number of simulated datasets and thus beused to infer likely sources of heterogeneity. We then use this new diagnostic tool on two stated choice case studies. For the first, we find that the use of model averaging leads to significant reductions in the amount of heterogeneity of the type analysts have sought to uncover with latent class structures of late. For the second, results from model averaging show clear evidence of the existence of both taste and decision rule heterogeneity. Overall, however, our results suggest that heterogeneity in the sensitivities to individual attributes rather than the behavioural process per se could be the key factor behind the improvements gained through the adoption of latent class models for heterogeneity in behavioural processes.
{"title":"What is really uncovered by mixing different model structures: contrasts between latent class and model averaging","authors":"Thomas O. Hancock, S. Hess","doi":"10.18757/EJTIR.2021.21.3.3949","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.3.3949","url":null,"abstract":"Latent class models have long been a tool for capturing heterogeneity across decisionmakers in the sensitivities to individual attributes. More recently, there has been increased interest in using these models to capture heterogeneity in actual behavioural processes, such as information/attribute processing and decision rules. This often leads to substantial improvement in model fit and the apparent finding of large clusters of individuals making choices in ways that are substantially different from those used by others. Such findings have however not been without criticism given the potential risk of confounding with other more modelspecific heterogeneity. In this paper, we consider an alternative approach for exploring the issue by contrasting the findings obtained with model averaging, which combines the results from a number of separately (rather than simultaneously) estimated models. We demonstrate that model averaging can accurately recover the different data generation processes used to create a number of simulated datasets and thus beused to infer likely sources of heterogeneity. We then use this new diagnostic tool on two stated choice case studies. For the first, we find that the use of model averaging leads to significant reductions in the amount of heterogeneity of the type analysts have sought to uncover with latent class structures of late. For the second, results from model averaging show clear evidence of the existence of both taste and decision rule heterogeneity. Overall, however, our results suggest that heterogeneity in the sensitivities to individual attributes rather than the behavioural process per se could be the key factor behind the improvements gained through the adoption of latent class models for heterogeneity in behavioural processes.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48604347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-08DOI: 10.18757/EJTIR.2021.21.3.5283
Jan Hendrik Van Petegem, P. Schepers, G. Wijlhuizen
Bicycle infrastructure is utilised to improve cycling safety and encourage bicycle use as a sustainable and healthy transport mode. This study sets out to assess whether providing physically separated cycle tracks along distributor roads, as prescribed in Dutch design guidelines and the Sustainable Safety vision, yields the expected safety benefits for cyclists. Therefore the safety of physically separated cycle tracks is compared to marked or painted cycle lanes and to mixed traffic conditions at distributor roads with a speed limit of 50 km/h in Amsterdam in the Netherlands. The study also includes the presence of the risk factors curbside parking and trams. Since police records are known to underreport single bicycle crashes and other crashes without a motor vehicle involved, ambulance records are used in this study instead. Also, both motor vehicle volumes as well as cyclists counts are taken into account in the crash analysis. By doing so, this study aims to address two weaknesses of previous research, i.e. the lack of control for exposure of cyclists and the use of police recorded crashes which miss the majority of bicycle crashes without motor vehicles. Results show that, controlled for kilometres travelled by bicycle and by motor vehicle, 50-60% less bicycle crashes occur on distributor roads with cycle tracks compared to those with cycle lanes. Curbside parking and trams are related to an increased likelihood of bicycle crashes, a difference of a factor 2 and 1.7-2 respectively. The authors therefore recommend to favour physically separated cycle tracks over cycle lanes and to take out curbside parking from the cross section as this presents the possibility to introduce cycle tracks in existing cross sections and mitigate an important risk factor concurrently.
{"title":"The safety of physically separated cycle tracks compared to marked cycle lanes and mixed traffic conditions in Amsterdam","authors":"Jan Hendrik Van Petegem, P. Schepers, G. Wijlhuizen","doi":"10.18757/EJTIR.2021.21.3.5283","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.3.5283","url":null,"abstract":"Bicycle infrastructure is utilised to improve cycling safety and encourage bicycle use as a sustainable and healthy transport mode. This study sets out to assess whether providing physically separated cycle tracks along distributor roads, as prescribed in Dutch design guidelines and the Sustainable Safety vision, yields the expected safety benefits for cyclists. Therefore the safety of physically separated cycle tracks is compared to marked or painted cycle lanes and to mixed traffic conditions at distributor roads with a speed limit of 50 km/h in Amsterdam in the Netherlands. The study also includes the presence of the risk factors curbside parking and trams. Since police records are known to underreport single bicycle crashes and other crashes without a motor vehicle involved, ambulance records are used in this study instead. Also, both motor vehicle volumes as well as cyclists counts are taken into account in the crash analysis. By doing so, this study aims to address two weaknesses of previous research, i.e. the lack of control for exposure of cyclists and the use of police recorded crashes which miss the majority of bicycle crashes without motor vehicles. Results show that, controlled for kilometres travelled by bicycle and by motor vehicle, 50-60% less bicycle crashes occur on distributor roads with cycle tracks compared to those with cycle lanes. Curbside parking and trams are related to an increased likelihood of bicycle crashes, a difference of a factor 2 and 1.7-2 respectively. The authors therefore recommend to favour physically separated cycle tracks over cycle lanes and to take out curbside parking from the cross section as this presents the possibility to introduce cycle tracks in existing cross sections and mitigate an important risk factor concurrently.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49427944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-07DOI: 10.18757/EJTIR.2021.21.3.4165
Igor Y. Davydenko, L. Tavasszy, H. J. (Hans) Quak
Several studies show that logistics facilities have spread spatially from relatively concentrated clusters in the 1970s to geographically more decentralized patterns away from urban areas. The literature indicates that logistics costs are one of the major influences on changes in distribution structures, or locations and usage of logistics facilities. Quantitative modelling studies that aim to describe or predict these phenomena in relation to logistics costs are lacking, however. This is relevant to design more effective policies concerning spatial development, transport and infrastructure investments as well as for understanding environmental consequences of freight transport. The objective of this paper is to gain an understanding of the responsiveness of spatial logistics patterns to changes in these costs, using a quantitative model that links production and consumption points via distribution centers. The model is estimated to reproduce observed use of logistics facilities as well as related transport flows, for the case of the Netherlands. We apply the model to estimate the impacts of a number of scenarios on the spatial spreading of regional distribution activity, interregional vehicle movements and commodity flows. We estimate new cost elasticities, of the demand for trade and transport together, as well as specifically for the demand for the distribution facility services. The relatively low cost elasticity of transport services and high cost elasticity for the distribution services provide new insights for policy makers, relevant to understand the possible impacts of their policies on land use and freight flows.
{"title":"On the cost elasticity of inter-regional distribution structures: a case study for the Netherlands","authors":"Igor Y. Davydenko, L. Tavasszy, H. J. (Hans) Quak","doi":"10.18757/EJTIR.2021.21.3.4165","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.3.4165","url":null,"abstract":"Several studies show that logistics facilities have spread spatially from relatively concentrated clusters in the 1970s to geographically more decentralized patterns away from urban areas. The literature indicates that logistics costs are one of the major influences on changes in distribution structures, or locations and usage of logistics facilities. Quantitative modelling studies that aim to describe or predict these phenomena in relation to logistics costs are lacking, however. This is relevant to design more effective policies concerning spatial development, transport and infrastructure investments as well as for understanding environmental consequences of freight transport. The objective of this paper is to gain an understanding of the responsiveness of spatial logistics patterns to changes in these costs, using a quantitative model that links production and consumption points via distribution centers. The model is estimated to reproduce observed use of logistics facilities as well as related transport flows, for the case of the Netherlands. We apply the model to estimate the impacts of a number of scenarios on the spatial spreading of regional distribution activity, interregional vehicle movements and commodity flows. We estimate new cost elasticities, of the demand for trade and transport together, as well as specifically for the demand for the distribution facility services. The relatively low cost elasticity of transport services and high cost elasticity for the distribution services provide new insights for policy makers, relevant to understand the possible impacts of their policies on land use and freight flows.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47657676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-17DOI: 10.18757/EJTIR.2021.21.2.5368
C. Saba, N. Ngepah, N. Odhiambo
This study investigates the convergence in transport infrastructure for 102 countries spanning 1990-2018 using Phillips and Sul econometric methodology. We constructed a transportation infrastructure by a composite index of transportation computed via principal component analysis (PCA). Our findings suggest the presence of panel convergence at the global level, while the income groups exhibited panel divergence. The results obtained from the iterative testing procedure suggest that the sub-groups exhibited convergence and divergence features. Overall, this study finds that the process of convergence in transportation reflects the desirable emanations of transportation policies sharing possible similar characteristics, at least to some extent, across the globe.
{"title":"Analysis of convergence in transport infrastructure: a global evidence","authors":"C. Saba, N. Ngepah, N. Odhiambo","doi":"10.18757/EJTIR.2021.21.2.5368","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.2.5368","url":null,"abstract":"This study investigates the convergence in transport infrastructure for 102 countries spanning 1990-2018 using Phillips and Sul econometric methodology. We constructed a transportation infrastructure by a composite index of transportation computed via principal component analysis (PCA). Our findings suggest the presence of panel convergence at the global level, while the income groups exhibited panel divergence. The results obtained from the iterative testing procedure suggest that the sub-groups exhibited convergence and divergence features. Overall, this study finds that the process of convergence in transportation reflects the desirable emanations of transportation policies sharing possible similar characteristics, at least to some extent, across the globe.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48684811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-04DOI: 10.18757/EJTIR.2021.21.2.5504
J. Park
Infrastructure projects around the world have long been notorious for exceeding their budgets. To address persistent cost overruns, the American Planning Association urged planners to adopt reference class forecasting alongside traditional methods but the practice has not caught on in the U.S. Conversely, the U.K. adopted Kahneman’s Nobel Prize-winning theory to challenge biases in human judgment and mandated reference class forecasting for major projects in 2003. Has reference class forecasting, originally developed to rectify honest mistakes, brought the promised success in the public sector wherein political pressure is significant? Through before-and-after and with-and-without comparisons of 107 major projects, this empirical study examines the practical relevance of reference class forecasting for infrastructure investments. A before-and-after comparison reveals that the average cost overrun declined from 38% to 5% following the introduction of reference class forecasting. A with-and-without comparison also demonstrates that the U.K. surpassed its targeted probability of completing projects within budget by 12% using reference class forecasting, whereas the U.S. underperformed by 17%. Thus, reference class forecasting has engendered notable improvements in estimation in the U.K. This empirical study demonstrates the benefits of supplementing or replacing the current forecasting method. The findings can be used to reduce substantial financial risks for the government as well as social and economic welfare losses for society.
{"title":"Curbing cost overruns in infrastructure investment","authors":"J. Park","doi":"10.18757/EJTIR.2021.21.2.5504","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.2.5504","url":null,"abstract":"Infrastructure projects around the world have long been notorious for exceeding their budgets. To address persistent cost overruns, the American Planning Association urged planners to adopt reference class forecasting alongside traditional methods but the practice has not caught on in the U.S. Conversely, the U.K. adopted Kahneman’s Nobel Prize-winning theory to challenge biases in human judgment and mandated reference class forecasting for major projects in 2003. Has reference class forecasting, originally developed to rectify honest mistakes, brought the promised success in the public sector wherein political pressure is significant? Through before-and-after and with-and-without comparisons of 107 major projects, this empirical study examines the practical relevance of reference class forecasting for infrastructure investments. A before-and-after comparison reveals that the average cost overrun declined from 38% to 5% following the introduction of reference class forecasting. A with-and-without comparison also demonstrates that the U.K. surpassed its targeted probability of completing projects within budget by 12% using reference class forecasting, whereas the U.S. underperformed by 17%. Thus, reference class forecasting has engendered notable improvements in estimation in the U.K. This empirical study demonstrates the benefits of supplementing or replacing the current forecasting method. The findings can be used to reduce substantial financial risks for the government as well as social and economic welfare losses for society.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46261400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-26DOI: 10.18757/EJTIR.2021.21.2.5354
S. Calvert, G. Mecacci, D. Heikoop, R. Janssen
Vehicle cooperation, not vehicle automation, will yield the greatest benefits on road traffic. However, satisfactory human control over platoons of cooperative vehicles still has a large number of uncertainties and issues to be addressed. This paper aims to address these broader issues of control over a cooperative vehicle platoon by focussing on a truck platooning system as a case example, and taking the perspective of Meaningful Human Control (MHC) as control concept. MHC goes further than mere operational control as it addresses issues that exist in current system designs, and proposes improvements based on a novel and more encompassing set of conditions for control. These issues are addressed in regard to the vehicles and their Operational Design Domains (ODD), the role and ability of the drivers (both leading and following) and how these exist in regard to their road environment. We conclude that current advances are making progress, but that from a MHC perspective, issues still remain for the operational and tactical implementation of truck platoons and cooperative driving that need to be addressed in regard to ODDs and drivers. Furthermore, consideration of responsibility and liability aspects is required that stretches beyond nominal appointment thereof, as this does not satisfy important ethical and societal standards. This is demonstrated in the paper through two hypothetical cases focussing on issues on a system level and one further analysis which is focussed on the role of the driver in the platooning system.
{"title":"How to ensure control of cooperative vehicle and truck platoons using Meaningful Human Control","authors":"S. Calvert, G. Mecacci, D. Heikoop, R. Janssen","doi":"10.18757/EJTIR.2021.21.2.5354","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.2.5354","url":null,"abstract":"Vehicle cooperation, not vehicle automation, will yield the greatest benefits on road traffic. However, satisfactory human control over platoons of cooperative vehicles still has a large number of uncertainties and issues to be addressed. This paper aims to address these broader issues of control over a cooperative vehicle platoon by focussing on a truck platooning system as a case example, and taking the perspective of Meaningful Human Control (MHC) as control concept. MHC goes further than mere operational control as it addresses issues that exist in current system designs, and proposes improvements based on a novel and more encompassing set of conditions for control. These issues are addressed in regard to the vehicles and their Operational Design Domains (ODD), the role and ability of the drivers (both leading and following) and how these exist in regard to their road environment. We conclude that current advances are making progress, but that from a MHC perspective, issues still remain for the operational and tactical implementation of truck platoons and cooperative driving that need to be addressed in regard to ODDs and drivers. Furthermore, consideration of responsibility and liability aspects is required that stretches beyond nominal appointment thereof, as this does not satisfy important ethical and societal standards. This is demonstrated in the paper through two hypothetical cases focussing on issues on a system level and one further analysis which is focussed on the role of the driver in the platooning system.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49588895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-26DOI: 10.18757/EJTIR.2021.21.2.5469
A. Colling, R. Hekkenberg, E. V. Hassel
To achieve a modal shift towards waterborne transport and to deal with the shortage of crewmembers, a platooning concept called the “Vessel Train” is explored for the inland navigation sector. A Vessel Train consists of a lead and various follower vessels. The lead vessel is fully manned and takes over the navigational and situational awareness responsibilities for the follower vessels. This leading action benefits the followers through increasing the vessels’ productivity and enabling crew cost savings. This article investigates the viability of the concept for the lower Rhine region, by presenting a cost model that compares the Vessel Train conditions to the current sailing conditions. This model is used to assess a case study where lead vessels operate on a liner service between Antwerp and Duisburg. Economically viable cases for the concepts’ early-stage application and fully matured implementation are identified, and boundary conditions are presented. The viable conditions vary depending on the vessel type and the operating regime of the reference vessel. A fully matured VT implementation requires a minimum of 26 participants, whereas an early-stage implementation requires 40 participants. The early-stage implementation additionally includes a minimum distance of 200 km to be spent sailing in the VT and the distance sailed in the VT has to amount to a minimum of 50% of the entire trip.
{"title":"A Viability Study of Waterborne Platooning on the Lower Rhine","authors":"A. Colling, R. Hekkenberg, E. V. Hassel","doi":"10.18757/EJTIR.2021.21.2.5469","DOIUrl":"https://doi.org/10.18757/EJTIR.2021.21.2.5469","url":null,"abstract":"To achieve a modal shift towards waterborne transport and to deal with the shortage of crewmembers, a platooning concept called the “Vessel Train” is explored for the inland navigation sector. A Vessel Train consists of a lead and various follower vessels. The lead vessel is fully manned and takes over the navigational and situational awareness responsibilities for the follower vessels. This leading action benefits the followers through increasing the vessels’ productivity and enabling crew cost savings.\u0000This article investigates the viability of the concept for the lower Rhine region, by presenting a cost model that compares the Vessel Train conditions to the current sailing conditions. This model is used to assess a case study where lead vessels operate on a liner service between Antwerp and Duisburg. Economically viable cases for the concepts’ early-stage application and fully matured implementation are identified, and boundary conditions are presented. The viable conditions vary depending on the vessel type and the operating regime of the reference vessel. A fully matured VT implementation requires a minimum of 26 participants, whereas an early-stage implementation requires 40 participants. The early-stage implementation additionally includes a minimum distance of 200 km to be spent sailing in the VT and the distance sailed in the VT has to amount to a minimum of 50% of the entire trip.","PeriodicalId":46721,"journal":{"name":"European Journal of Transport and Infrastructure Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2021-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48917522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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