21 research outputs found
On the Link between Urban Form and Automobile Use - Evidence from German Survey Data
This study investigates the influence of urban form on automobile travel using travel-diary data from Germany. Two dimensions of car use are considered: the discrete decision to own a car and the continuous decision of distance traveled. Because these decisions are likely to be influenced by factors unobservable to the researcher, we apply censored regression models to evaluate the role of biases emerging from sample selectivity. Unlike much of the literature, we find that urban form variables are a significant determinant of both automobile ownership and use, a finding that holds even after using instrumental variables to control for endogeneity.urban form, non-work automobile travel, sample selectivity, instrumental variables
TOWARDS INTEROPERABILITY IN THE EUROPEAN RAILWAY SYSTEM – EVALUATION OF PROMISING STRATEGIES WITHIN THE REORIENT PROJECT
Within the European Commission’s 6th Framework Programme, the REORIENT
project is investigating ways to provide seamless international rail freight transport, in order to make rail transport more attractive and increase the share of freight being transported by rail. In order to achieve its objective, the REORIENT Consortium developed a methodology that includes surveys, data collection, network modelling, and evaluation tools. The paper presents an overview of these methods and focuses on the planned project activities to evaluate promising strategies. Effects related to competitiveness, societal welfare and equity are evaluated applying cost-benefit-analysis and the multi-criteria decision aiding approach ELECTRE III
Multikriterielle Bewertung von Strategien zur Förderung des europäischen Schienengüterverkehrs (English: Multicriteria evaluation of strategies to promote European rail freight transport.)
Abstract
Provided a high degree of capacity utilisation, the transport of goods on rails represents an environmentally, economically and socially advantageous mode of transport when compared to road haulage. As its current low mode-share in Europe reveals, however, rail freight transport is a competitive alternative only in a minority of cases
Is there a link between urban form and automobile use in Germany? Evidence from a selectivity model
This study estimates an econometric model of the influence of urban form on non-work automobile travel using a panel of travel-diary data collected in Germany between 1994 and 2003. Two dimensions of car use are considered: the discrete decision to own a car and the continuous decision of distance traveled. Because these decisions are related and, moreover, are likely to be influenced by factors unobservable to the researcher, we apply the Heckman model to control for potential biases emerging from sample selectivity. In addition to including variables that capture the tools commonly advocated by land use planners to influence mobility behavior, an important contribution of this study is to allow the possibility that these variables are endogenous. Unlike much of the work to date, we find that land use variables are a significant determinant of both automobile ownership and use, a finding that holds even after using instrumental variables to capture the effects of urban form
On the application ELECTRE III to the analysis of rail freight options: Advances in assessing the sensitivity of rankings.
This paper explores the application of the ELECTRE III multicriteria decision-making tool to evaluate alternative policy strategies for promoting seamless freight transport along a rail corridor connecting the Nordic region with Central and Southeastern Europe.
ELECTRE III is based on successive pairwise comparisons of two alternatives to establish outranking relations with respect to a pre-determined set of criteria. Among the advantages of the method is its flexibility in: (1) simultaneously incorporating both quantitative (e.g. monetized) and qualitative outcome indicators; (2) handling uncertainty in the data; and (3)
allowing for indifference, preference and veto thresholds with respect to each of the indicators. We explore these advantages through an analysis that focuses on the economic, social, and environmental effects that would emerge from a rebalancing of freight traffic from road to rail. The paper moves beyond the existing literature on ELECTRE III in two respects.
First, we develop an automated tool that allows the analyst to systematically vary key parameters (e.g. preference weights) and thereby test the sensitivity of the results. Second, we demonstrate how the findings of the sensitivity analysis can be presented by means of an intuitive graphical depiction of shifts in the rankings that can be readily interpreted by
decision-makers. As the research for this paper is conducted under the auspices of a recently launched international consortium, REORIENT, which is funded by the European Commission, we are currently reliant on the use of hypothetical data to demonstrate the results
The Impact of Urban Form on Automobile Travel: Disentangling Causation from Correlation
A longstanding question within the field of transportation demand management is the strength of the relationship between urban form and mobility behavior. Although several studies have identified a strong correlation between these variables, there is as yet scant evidence to support policy interventions that target land use as a means of influencing travel. To the contrary, some of the more recent research has cast skepticism on the proposition that the relationship is causative, recognizing the possibility that households endogenously self-select themselves into communities that support their preferences for particular transportation modes. Focusing on individual automobile travel, the present study seeks to contribute to this line of inquiry by estimating econometric models on a panel of travel-diary data collected in Germany between 1996 and 2003. Specifically, we employ the two-part model (2PM) – a procedure involving probit and OLS estimators – to assess the determinants of the discrete decision to use the car and the continuous decision of distance traveled. Beyond modeling variables that capture the urban form features that are commonly suggested to influence mobility behavior, including mixed use and public transit, this study employs instrumental variables to control for potential endogeneity emerging from the simultaneity of residential and mode choices. Unlike much of the work to date, our results suggest that urban form has a causative impact on car use, a finding that is robust to alternative econometric specifications
ON THE LINK BETWEEN URBAN FORM AND AUTOMOBILE USE: EVIDENCE FROM GERMAN SURVEY DATA
This study investigates the influence of urban form on automobile travel using travel-diary data from Germany. Two dimensions of car use are considered: the discrete decision to own a car and the continuous decision of distance traveled. Because these decisions are likely to be influenced by factors unobservable to the researcher, we apply censored regression models to evaluate the role of biases emerging from sample selectivity. Unlike much of the literature, we find that urban form variables are a significant determinant of both automobile ownership and use, a finding that holds even after using instrumental variables to control for endogeneity
Damage Functions for Transport Infrastructure
Purpose: Damage functions constitute an essential part of the modelling of critical infrastructure (CI) performance under the influence of climate events. This paper aims to compile and discuss publications comprising damage functions for transport assets. Design/methodology/approach: The research included the collection of contemplable literature and the subsequent screening for damage functions and information on them. In conclusion, the derived damage curves and formulae were transferred to a unified design. Findings: Damage functions for the transport sector are scarce in the literature. Although specific damage functions for particular transport assets exist, they mainly consider infrastructure or transport in general. Occasionally, damage curves for the same asset in different publications vary. Major research gaps persist in wildfire damage estimation. Research limitations/implications: The study scope was restricted to the hazards of fluvial floods and wildfires. Despite all efforts, this study did not cover all existing literature on the topic. Originality/value: This publication summarises the state of the art of research concerning transport asset damage functions, and hence contributes to the facilitation of prospective research on CI performance, resilience and vulnerability modelling