Participatory value evaluation (PVE) is a novel method aiming at the evaluation of projects from a societal perspective. It aims at establishing which investment projects or investment portfolios (with a portfolio containing multiple investment projects) are likely to be favored by the population, given a limited budget. The approach emulates the decision-making problem faced by policy-makers. The ultimate end of PVE is to evaluate and establish how individuals value attributes of public projects in order to construct social trade-offs between different attributes and investments projects. However, it is important to consider that when investment portfolios consist of more than one investment project, significant synergies (positive and negative) may exist among the projects. This paper proposes a new evaluation framework that allows addressing synergies among projects in the context of PVE, while also offering a highly flexible structure. The approach is tested making use of one synthetic and two real datasets. Results show that neglecting synergies among the utilities of the projects included in the chosen portfolio majorly reduces the model fit and biases the estimators.

While several governmental and research efforts are set upon mobility-as-a-service (MaaS), most of them are driven by individual travel behavior and potential usage. However, considering only individuals’ preferences carries the risk of neglecting societal benefits going beyond individual travel behavior. This study addresses the valuation of different features of MaaS-services from a social desirability perspective as compared to social investments in biking infrastructure and in public transport, and aims at eliciting trade-offs between different features of such projects. This analysis is conducted on the basis of Participatory Value Evaluation (PVE). In PVE-experiments, individuals select their preferred portfolio of government projects given a constrained public budget and societal preferences for (the impacts of) government projects can be determined based on these choices. The results show that the population of Rotterdam exhibits a willingness to allocate public resources to all types of investment projects considered in the analysis. However, the willingness to allocate resources to bike infrastructure projects and public transport seems to be higher than the willingness to dedicate resources to MaaS subsidies. Within the different types of MaaS subsidies considered, subsidies aimed at sustainability exhibit a larger social valuation. Strong negative synergies among similar projects exist, signalizing that individuals prefer diversifying the use of public resources across different types of investment projects.