Exploring heterogeneity in travel time expenditure of aging populations in the Netherlands: results of a CHAID analysis

The aim of this paper is to contribute to the increasing literature on travel behavior and time use of the elderly. The Dutch National Travel Survey, administered in 2009, was used as a data source. First, various facets of activity-travel patterns of the elderly were compared against overall sample averages. Results indicate that the new generation of elderly people do not differ that much from other age groups in terms of their activity-travel behavior. Differences in behavior can be largely understood in terms of constraints acting on agendas. Moreover, travel patterns of elderly are affected by socio-demographic variables. Second, to further qualify the average findings, the Chi-square automatic interaction detection (CHAID) method was applied to explore heterogeneity among the elderly in terms of travel time expenditure. It is analyzed how differences in travel time co-vary with socio-demographics, in addition to activity type, activity duration and travel aspects. The results suggest that the aging population can be systematically broken down into several homogeneous cohort segments. Travel time of elderly groups depends significantly on transport modes, travel motivation, and seven socio-demographic variables (gender, age, living environment, personal net-income, household size and season). Moreover, there is less heterogeneity in travel time of elderly who are older than 75 years old. However, for younger elderly people, especially the group aged from 65 to 74 years old, heterogeneity affects their travel.     

Exploring the choice of battery electric vehicles in city logistics: A conjoint-based choice analysis

Adoption of electric vehicles by transport companies remains limited although major European cities should reach CO₂-free city logistics by 2030. This paper explores therefore the vehicle choice behaviour of transport companies through a conjoint-based choice analysis.The results showed that the benefits of battery electric vehicles are less valued than their disadvantages. However, a majority of respondents agrees that authorities should encourage the use of battery electric vehicles. Based on the preferences of transporters, we conclude that the most important measures are to develop a larger charging infrastructure and implement financial incentives through subsidies or tax exemption.     

Determinants of sustainable mode choice in different socio-cultural contexts: A comparison of Rome and San Francisco

This paper is a part two of a study investigating the relative importance of the built environment, socio-demographic, and attitudinal factors on mode choice. A semi-experimental approach that aims to measure causal effects of the built environment is utilized. This paper reports spatial analysis, survey and modeling results for San Francisco, CA, USA and compares the results with a previous similar study in Rome, Italy. Results reveal that the local street network's integration is important in both cities and that in both cases built environment seems to have higher impact on mode choice than attitudes and socio-demographic factors. Built environment is especially impactful when diversity, design quality, density and syntactical accessibility are combined. In San Francisco willingness to spend time walking, biking or taking transit is lower than in Rome, and residents are more sensitive to concerns about safety and security. Work travel is more affected by demographic and attitudinal factors in San Francisco than in Rome implying that in San Francisco, nonwork travel behavior may have slightly higher potential to respond positively to improvements in the built environment than work trips. In Rome, peer pressure, cost sensitivity, and probiking attitude can compensate for lack of some built environmental characteristics, but not in San Francisco, where only protransit attitude has this effect. Moreover, lack of any built environmental characteristics reduces the possibility of sustainable mode choice more dramatically in San Francisco pointing to the higher importance of investments on improving the built environment rather than marketing efforts to change attitudes.