On the Interplay of Acceptance of Crowd-Sourced Delivery and Transportation Mode Choice within a MaaS Service

Crowd-Sourced Delivery (CSD) has emerged as an innovative approach to last-mile parcel delivery, offering the potential to reduce traffic congestion and CO₂ emissions in urban areas. However, existing CSD models typically rely on a limited pool of crowd-shippers, primarily private car drivers or public transport passengers registered on dedicated CSD platforms. This typical service setup poses operational challenges, as the availability of a sufficient number of crowd-shippers is critical to the effectiveness and operational feasibility of CSD systems. To address this limitation, this study proposes integrating CSD into Mobility-as-a-Service (MaaS). This integration would allow travelers to fulfill their mobility needs through a variety of transportation modes within MaaS while simultaneously undertaking parcel delivery tasks as crowd-shippers, all using a single application. Such an integration has the potential to expand the pool of available crowd-shippers beyond private car drivers or public transport passengers registered on dedicated CSD platforms to a broader range of daily travelers. This, in turn, can enhance the operational efficiency of CSD services while providing prospective crowd-shippers with greater flexibility in selecting their transportation mode, particularly by encouraging the use of sustainable transportation options. In this context, this study aims to investigate end-users’ preferences regarding transportation mode choice and the willingness to accept CSD tasks within MaaS-CSD integrated service. Specifically, it explores the decision-making process underlying these choices, focusing on their interdependence and key influencing factors, including both observable and unobservable individual characteristics, CSD task and transport mode characteristics, and broader travel contexts. Additionally, since CSD is promised to be a sustainable solution, it is important to examine whether the acceptance of a CSD task has any influence on the choice of transportation mode and if so what the direction of influence is. Only then can the true impact of CSD on sustainability be understood. To achieve these research objectives, this study conducted a stated choice survey incorporating two-step. In the first step, respondents were presented with hypothetical trips and asked to select a transportation mode from a given set, each described with attributes such as cost and travel time. Simultaneously, they were shown two CSD tasks and asked whether they would accept either of them. In the second step, respondents who accepted a delivery task were asked to indicate which transportation mode they would have chosen had CSD tasks not been available, while keeping all other travel conditions and transport options unchanged. The experiment was embedded within a web-based survey, which also collected data on socio-demographic characteristics, and attitudes characterizing the transportation modes and CSD tasks. A total of 774 respondents from the Netherlands participated in the study, generating 6,192 observations for the analysis. This thesis provides analysis results examining heterogeneity in transportation mode choice and the acceptance of CSD tasks based on data collected from the first step of the stated choice experiment, alongside socio-demographic characteristics and attitudinal factors. Given the innovative nature of CSD integration within MaaS, it is essential to understand how individuals perceive this integration and to explore their decision-making processes regarding transportation mode selection and the acceptance or rejection of delivery tasks. Since CSD plays a secondary role in travelers’ decision-making, we investigate preference heterogeneity using two decision paradigms: one in which transportation modes and delivery tasks are chosen simultaneously, and second paradigm where transportation mode selection takes priority. To capture these distinct decision-making patterns, a hybrid latent class model with class-specific choice paradigms was estimated. The results indicate that 43.0% of respondents follow the simultaneous choice paradigm and are classified as CSD enthusiasts. These individuals tend to be younger, highly educated, and urban residents with a higher propensity to accept delivery tasks. Conversely, respondents who prioritize transportation mode over delivery tasks are categorized as CSD indifferent and exhibit a lower likelihood of participating in CSD. However, the findings suggest that CSD indifferent individuals have potential to be crowd-shippers if they become more aware of the benefits associated with CSD integration. The analysis also reveals differences in decision-making criteria between these groups. CSD enthusiasts primarily consider task-related attributes such as parcel size, weight, and detour requirements, whereas CSD indifferent individuals are more concerned with delivery-related risks, including potential damage and penalties. Moreover, the integration of CSD has a modest impact on transportation mode choice, particularly increasing car usage among CSD enthusiasts due to its compatibility with parcel delivery, which may conflict with the sustainability goals of MaaS and CSD itself. Nevertheless, the results suggest that promoting sustainable modes for CSD is achievable by matching parcels with such modes. Another analysis examines the acceptance of CSD tasks across various transportation mode options. The potential of CSD for alleviating emissions and traffic jams can be best realized if most of tasks are done during the trips made by active or public modes as opposed to car-based modes. Moreover, it is expected that users of different modes have different preferences regarding the type of parcel (size, weight, fragility) they are being allocated due to different levels of convenience associated with various modes. To understand the willingness of travelers to accept a CSD task across different transportation modes, and type of parcels suitable for users of different modes, an error component mixed logit model was employed to assess the effects of various transportation and parcel related factors on travelers’ decisions while accounting for the correlation between transportation modes with similar features. The results indicate that the willingness to accept a parcel delivery task varies significantly across transportation modes. Car-based modes, particularly private cars, were the most preferred, while sustainable modes such as private (E-)bikes and public transport demonstrated notable potential. Conversely, emerging shared mobility modes were less favored as carriers in CSD. Additionally, delivery task characteristics, travel contexts, and socio-demographic factors significantly influenced the decision to accept a delivery task, with varying effects across transportation modes. The third analysis examines the impact of accepting a CSD task on transportation mode choice. Given that MaaS aims to promote sustainable transportation and reduce reliance on car-based travel, this study investigates whether engaging in CSD influences individuals’ transportation mode decisions in ways that either support or undermine sustainability goals. Specifically, respondents’ transportation mode choices were captured both with and without CSD tasks to assess behavioral shifts. To analyze these effects, a mixed logit model with random alternative-specific constants was estimated, identifying the factors influencing changes in transportation mode choice upon accepting a CSD task. The results indicate that CSD integration can sometimes shift travelers’ preferences from public transport and active modes toward car-based travel, suggesting that car-based transport remains the preferred option for parcel delivery. However, several factors were found to encourage the use of sustainable transport modes, including public and active transportation. These factors include transporting non-fragile parcels, having a less strict delivery time window, and receiving higher monetary incentives for using sustainable modes. Additionally, travel contexts, such as trip distance and weather conditions, along with socio-demographic characteristics, particularly respondents' age, significantly influence transportation mode choice when a delivery task is accepted. Furthermore, pseudo-elasticity analysis revealed that travel context and socio-demographic factors exert a stronger influence on increasing the use of sustainable transportation modes than the specific characteristics of the CSD tasks themselves. In conclusion, the findings indicate that, within the context of integrating CSD into MaaS, car-based modes, particularly private cars, remain the preferred option for parcel delivery. The integration of CSD may even inadvertently increase the adoption of car-based modes for daily travel. At the same time, the use of sustainable transportation modes can be promoted through careful allocation of delivery tasks that consider parcel characteristics (e.g., size, weight, and type) alongside travel contexts such as weather and travel distance. Operational efficiency and environmental sustainability can be further enhanced by tailoring CSD tasks to different traveler segments with diverse socio-demographic profiles. This study contributes to a deeper understanding of transportation mode choice and decision of accepting a CSD task within the context of integrating CSD into MaaS, as well as underscores the potential of CSD-MaaS to enhance operational efficiency and environmental sustainability, offering a foundation for future policy interventions and service design improvement.