Investigating inter-generational changes in activity-travel behavior: a disaggregate approach

Investigation into the long-term trends in travel behavior is crucial for strategic development of transport systems and decisions about investment in transport infrastructures. There has been a debate about if there is a constant amount of time allocated for travel and thus an upper limit to daily travel demand. Recent studies have suggested a stagnated and even declining trend of car ownership and travel demand in developed countries (the so-called ‘peak car’ and ‘peak travel’ phenomenon). This study aims at exploring the possible long-term trends in activity-travel behavior in Hong Kong to shed some light on the ‘peak travel’ debate. We have acquired two large-scale datasets from Hong Kong’s Travel Characteristics Survey conducted a decade apart and applied propensity score matching to match individuals of similar socioeconomic backgrounds from different time periods and compare their activity-travel behavior. Results indicate that households and individuals with similar socioeconomic backgrounds at the two periods have distinctively different car ownership levels and daily travel and activity behaviors.