This PhD position at Utrecht University, within the Faculty of Veterinary Medicine and the Department of Population Health Sciences, focuses on agent-based modelling to understand and promote physical activity in urban environments. The successful candidate will join the Institute for Risk Assessment Sciences (IRAS) and collaborate with the Netherlands Organisation for Applied Scientific Research (TNO) and other interdisciplinary experts. The project aims to develop and extend agent-based models (ABM) that simulate how people move, make activity choices, and interact with their urban surroundings. Key research areas include integrating physical activity modules into spatial transport models, studying the influence of urban design, environmental stressors (such as heat, air pollution, and pollen), and social factors (like safety, norms, and networks) on active lifestyles. The candidate will develop and test models using diverse data sources, including sensors, surveys, Google Street View imagery, and microdata from sources like CBS Lifestyle Monitor and ODIN. Computational and AI-based modelling approaches will be employed to simulate the impact of urban interventions—such as green spaces, outdoor fitness equipment, and active transport policies—on population health and health equity. The research will include case studies in Dutch and potentially other European cities to evaluate real-world applications and policy impacts. The position offers a collaborative environment with urban planners, data scientists, and public health researchers. Applicants should have a Master’s degree in a relevant field, experience with programming and modelling, and strong analytical, quantitative, and communication skills. The position is initially for one year, with extension to four years upon positive evaluation, and includes a competitive salary, holiday pay, year-end bonus, pension scheme, and flexible employment terms. Utrecht University is committed to diversity and inclusion, providing a supportive environment for all staff. Applications are open until 31 December 2025.