The effects of ridesourcing services on vehicle ownership and the taxi market in the United Kingdom

Ridesourcing is among the new mobility services that disrupt the transportation sector and substantially affects the way people travel. As a low-capacity motorised mode, ridesourcing has attracted significant research interest due to its emerging impacts. While the short-term effects have been relatively well documented, the long-term impacts, especially on vehicle ownership, are only beginning to surface and remain underexplored. Although there has been a growing effort to discover the impact of ridesourcing on vehicle ownership, existing research on this subject tends to focus on specific countries, notably the US and China, with limited evidence from other parts of the world. The heterogeneity of impacts between and within countries revealed by the systematic literature review in this thesis calls for more evidence from different countries. Furthermore, the unique business model of ridesourcing complicates the investigation into its effects on vehicle ownership. On one hand, the potential for earning income using the existing or newly purchased vehicle may encourage vehicle ownership, known as the value enhancement effect. On the other hand, the reduced need for private vehicles after the introduction of ridesourcing services may cause a reduction in vehicle ownership, as a result of the substitution effect of ridesourcing. Hence, the overall effect is the sum of these opposing effects on the demand and the supply sides of the ridesourcing business and requires the consideration of both sides, as the value enhancement effect and the substitution effect can coexist.
This thesis contributes to the relevant literature by addressing these issues. Relying on official historical licensing records and a large longitudinal household survey data, the studies presented in this thesis econometrically model the impact of the availability of ridesourcing on vehicle ownership and the taxi market in the United Kingdom, where evidence is lacking. Moreover, the use of longitudinal datasets allows the investigation of the causal relationship between ridesourcing availability and vehicle ownership rather than an association.
The results suggest that the introduction of ridesourcing in the United Kingdom has not caused a statistically significant change in the overall number of passenger vehicles, despite the increased number of Private Hire Vehicles that also include ridesourcing. Moreover, the analysis of disaggregated dataset shows that UK households are less likely to acquire another car when ridesourcing is available for them. However, there is no statistically significant evidence showing that the availability of ridesourcing services has encouraged households to dispose of one of their cars. The heterogeneity in these effects is also considered in this thesis and the varying effects in London, metropolitan districts other than London, other urban areas and rural areas are investigated. The results suggest that the effect of ridesourcing on vehicle ownership in the UK is context-dependent on the demand side, but the response of the supply side is similar across different areas.
In addition, by combining the supply and demand side perspectives using both geographically aggregated and disaggregated datasets, this research provides insight into an overall picture of the impact of ridesourcing on the number of cars on the roads. The approach taken in this research allows for the study of shifts within the existing fleets, as well as new entrants and exits to the current transport system and helps gain insight into the actual impact on the number of cars in the system. The findings show that after the introduction of ridesourcing in the United Kingdom, the decrease in vehicle numbers as a result of the reduced need for private cars likely counterbalanced the increase in vehicle numbers associated with the value enhancement effect. However, the rise in the number of Private Hire Vehicles found in this thesis does not stem from new job creation for the broader public; instead, it reflects a shift within the existing personal mobility industry. Consequently, this has not spurred significant entry into the United Kingdom's taxi market nor has it driven substantial new vehicle purchases. By stopping households from purchasing another car, the introduction of ridesourcing seems to slow down the vehicle ownership rates in the United Kingdom but is yet to reverse the upward trend in vehicle ownership as it has not motivated household car disposal, at least for now.
Overall, by showing how the introduction of ridesourcing has affected vehicle ownership in the United Kingdom, this research provides a basis for understanding the wider impacts of ridesourcing as vehicle ownership is a critical determinant of car use and plays a key role in driving many of the transport and environmental externalities.