HASP: Generating synthetic mobility trajectories for privacy-preserving data sharing

One full PhD scholarship is available in the School of Geography. The successful applicant will be part of a cohort of four PhDs connected by the Healthy and Sustainable Places Data Service. This scholarship is open to UK and international applicants and covers fees plus maintenance and a research support fund.<br /> <br /> This fully funded PhD place provides an exciting opportunity to pursue postgraduate research in urban mobility data production, drawing in fields including machine learning, transport behaviour, and urban analytics.<br /> <br /> This PhD project will form part of the research programme within the Healthy and Sustainable Places (HASP) Smart Data Service, and therefore take place at the heart of discussions around the use of behavioural data for mobility research. <br />

<p style="margin-bottom:11px">The growth in the availability of fine-grained mobility data has spurred high-impact research findings into the nature of human mobility. There remains significant potential for enhanced understanding of mobility behaviour to help improve the reliability and sustainability of urban transportation systems. Despite major safeguards in place around the storage and use of fine-grained mobility data, there remain concerns about the risk to individual privacy, and questions about the continued willingness of the public to permit data for use in research.</p> <p>Synthetic data production has emerged as an important area of research in seeking to safeguard privacy, while enabling its continued use in understanding and modelling future cities. While researcher have proposed methodologies derived from machine learning techniques, such as Generative Adversarial Networks (GANs), Variational Autoencoders (VAEs), and diffusion models [1, 2], there remain questions about the how we encode demographics and contextual depth into these representations, while balancing similarity with privacy [3].</p> <p>This PhD project will seek to advance the state-of-the-art in synthetic trajectory production through the development of methods that better capture spatial, temporal, and contextual heterogeneity. We will seek to encode features such as travel mode choice, gender, age, and co-presence in our synthetic models. Furthermore, we will assess how we can account for, or integrate, non-recurrent events, such as travel disruptions, holidays, and weather, in realistically replicating mobility trajectories.</p> <p>Aside from the technical components of this study, there are broader conceptual issues. First, we must consider how we evaluate the performance of synthetic models in the context of an absence of comprehensive ground truth data. Second, we must consider how we balance performance against privacy preservation. When does an increasingly realistic model become too similar to real data? Finally, we must consider the spectrum of data and models, and how to broach a future of blended data sources, which encode elements of both.</p> <p>This PhD project will form part of the research programme within the Healthy and Sustainable Places (HASP) Smart Data Service, and therefore take place at the heart of discussions around the use of behavioural data for mobility research.</p> <p><strong>References</strong></p> <p>[1] Kapp, A., Hansmeyer, J. and Mihaljevic, H., 2023. Generative models for synthetic urban mobility data: A systematic literature review. <em>ACM Computing Surveys, 56</em>(4), pp.1-37. </p> <p>[2] Zhu, Y., Ye, Y., Zhang, S., Zhao, X. and Yu, J., 2023. DiffTraj: Generating GPS trajectory with diffusion probabilistic model. <em>Advances in Neural Information Processing Systems (NeurIPS), 36</em>, pp.65168-65188. </p> <p>[3] Benarous, M., Toch, E. and Ben-Gal, I., 2022. Synthesis of longitudinal human location sequences: Balancing utility and privacy. ACM Transactions on Knowledge Discovery from Data (TKDD), 16(6), pp.1-27. </p> <p><strong>Information about the Award</strong></p> <ul> <li>We are offering 1 full-time/part-time PhD scholarship in the School of Geography for one UK or international candidate, covering a matching UKRI maintenance stipend (£19,237 in 2024/25)  and tuition fees for 3.5 years, subject to satisfactory progress. Please note that international applicants must study on a full-time basis.</li> </ul> <p><strong>Duration of the Award</strong></p> <ul> <li>Full-time (3.5 years). The award will be made for one year in the first instance and renewable for a further period of up to 2.5 years, subject to satisfactory academic progress.</li> </ul> <p><strong>Other Conditions</strong></p> <ul> <li>Applicants must not have already been awarded or be currently studying for a doctoral degree.</li> <li>Awards must be taken up by 1st October 2025.</li> <li>Applicants must live within a reasonable distance of the University of Leeds whilst in receipt of this scholarship.</li> </ul>

<p style="margin-bottom:11px">To apply for this project you will need to make a formal application for research degree study through the <a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University's website</a>. You will need to create a login ID with a username and PIN.</p> <ul> <li>For ‘Application type’ please select ‘Research Degrees – Research Postgraduate’.</li> <li>The admission year for this project is 2025/2026 Academic Year.</li> <li>You will need to select your ‘Planned Course of Study’ from a drop-down menu. For this project, scroll down and select ‘PhD Geography Full-time’.</li> <li>The project start date for this project is 1st October 2025, please use this as your Proposed Start Date of Research.</li> <li><strong>Please state clearly in the research information section that the research degree you wish to be considered for is ‘HASP: Generating synthetic mobility trajectories for privacy-preserving data sharing’ as well as Professor <a href="https://environment.leeds.ac.uk/geography/staff/9293/professor-ed-manley">Ed Manley</a> as your proposed supervisor.</strong></li> </ul> <p>You will be required to provide a personal statement which outlines your interest in the project you are applying for, why you have chosen it and how your skills map onto the requirements of the project. You will also need to provide the following documents:</p> <ul> <li>certificates and transcripts of any academic qualifications</li> <li>English language qualification certificates, if applicable</li> <li>a copy of your CV</li> <li>visa and immigration documents, if applicable</li> </ul> <p>More information on how to apply is available on our website <a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees" rel="noreferrer noopener" target="_blank">here</a>.</p> <p>If English is not your first language, you must provide evidence that you meet the University's minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p>

The minimum entry requirements for PhD study is 2.1 honours degree, or equivalent, in geography or a related subject however a lower undergraduate degree can be supplemented by a relevant Masters degree.<br /> <br /> A first class honours degree (or equivalent) is usually required to be competitive for scholarship funding and a Masters degree is also a valuable asset.<br /> <br /> Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or PGR Admissions Team prior to making an application.<br />

The minimum English language entry requirement for postgraduate research study in the School of Geography is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid.

<p class="MsoNoSpacing">We are offering a fully funded scholarship to study the project ‘Generating synthetic mobility trajectories for privacy-preserving data sharing’, at the School of Geography, University of Leeds for one UK or international status candidate. The funding covers tuition fees as well as a UKRI matched maintenance stipend (currently £20,780 in 2025/26) per year, for 3.5 years, subject to satisfactory progress.</p>

<p>For further information please contact Professor Ed Manley (<a href="mailto:e.j.manley@leeds.ac.uk">e.j.manley@leeds.ac.uk</a>) or the Postgraduate Research Admissions Team (<a href="mailto:env-pgr@leeds.ac.uk">env-pgr@leeds.ac.uk</a>).</p>