Dr. Grigorios Loukides Senior Lecturer (Assoc. Prof.), Department of Informatics, King's College London   N. 5.13, Department of Informatics Bush House, 30 Aldwych, London, WC2B 4BG, UK tel: +44 20 7848 0553 Dr. Loukides is a Senior Lecturer (Associate Professor) in the Department of Informatics, King's College London. He was a Royal Academy of Engineering Research Fellow (2011-2016) at School of Computer Science & Informatics, Cardiff University and a Postdoctoral Research Fellow (2008-2011) at the Dept. of Biomedical Informatics, Vanderbilt University, USA. His research interests are in data mining. His research investigates theoretical and practical aspects including algorithmic design and optimization, and explores applications in social networks, healthcare, and business. He serves as an Associate Editor in IEEE Trans. on Information Forensics and Security (TIFS) and in Knowledge and Information Systems (KAIS) and as a PC member of conferences (e.g., KDD, ICDE, ICDM, SDM, WSDM, AAAI, and IJCAI). He is editor of Medical Data Privacy Handbook and author of Anonymization of Electronic Medical Records to Support Clinical Analysis. He is a Senior Member of IEEE and a Member of ACM.  Recent Publications 1. H. Verbeek, L. Ayad, G. Loukides, and S. P. Pissis. Minimizing the Minimizers via Alphabet Reordering.     Annual Symposium on Combinatorial Pattern Matching (CPM), 2024. (To appear) 2. G. Bernardini, H. Chen, I. L. Gørtz, C. Krogh, G. Loukides, S. P. Pissis, L. Stougie, and M. Sweering. Connecting de Bruijn Graphs.     Annual Symposium on Combinatorial Pattern Matching (CPM), 2024. (To appear) 3. E. Gabory, C. Liu, G. Loukides, S. P. Pissis, and W. Zuba. Space-Efficient Indexes for Uncertain Strings.     IEEE International Conference on Data Engineering (ICDE), 2024. (To appear) (arxiv version) (code) 4. H. Zhong, G. Loukides, A. Conte, and S. P. Pissis. Ego-Network Segmentation via (Weighted) Jaccard Median.     IEEE Transactions on Knowledge and Data Engineering (TKDE), 2024. (code) 5. P. Charalampopoulos, H. Chen, P. Christen, G. Loukides, N. Pisanti, S. P. Pissis, and J. Radoszewski. Pattern Masking for Dictionary Matching: Theory and Practice.     Algorithmica, 2024. 6. G. Bernardini, H. Chen, A. Conte, R. Grossi, V. Guerrini, G. Loukides, N. Pisanti, and S. P. Pissis. Utility-Oriented String Mining.     SIAM International Conference on Data Mining (SDM), 2024. (To appear) (pre-print) 7. H. Chen, A. Conte, R. Grossi, G. Loukides, S. P. Pissis, and M. Sweering. On Breaking Truss-Based and Core-Based Communities.     ACM Transactions on Knowledge Discovery from Data (TKDD), 2024. (code) 8. L. A. K. Ayad, G. Loukides, S. P. Pissis, and H. Verbeek. Sparse Suffix and LCP Array: Simple, Direct, Small, and Fast.     Latin American Symposium on Theoretical Informatics (LATIN), 2024. (arxiv version) (code) 9. L. A. K. Ayad, G. Loukides, and S. P. Pissis. Text Indexing for Long Patterns: Anchors are All you Need.     International Conference on Very Large Data Bases (VLDB), 2023. (code) 10. H. Chen, G. Loukides, R. Gwadera, and S. P. Pissis. Heavy Nodes in a Small Neighborhood: Algorithms and Applications.     SIAM International Conference on Data Mining (SDM), 2023. (code) 11. G. Loukides, S. P. Pissis, and M. Sweering. Bidirectional String Anchors for Improved Text Indexing and Top-K Similarity Search.     IEEE Transactions on Knowledge and Data Engineering (TKDE), 2023. (code) Selected Publications (more at: DBLP, Google Scholar) 1. H. Zhong, G. Loukies, A. Conte, and S. P. Pissis. Jaccard Median for Ego-Network Segmentation.     IEEE International Conference on Data Mining (ICDM), 2022. (code) 2. G. Bernardini, A. Conte, G. Gourdel, R. Grossi, G. Loukides, N. Pisanti, S. P. Pissis, G. Punzi, and L. Stougie, and M. Sweering.     Hide and Mine in Strings: Hardness, Algorithms, and Experiments.     IEEE Transactions on Knowledge and Data Engineering (TKDE), 2022. (code) 3. H. Chen, C. Dong, L. Fan, G. Loukides, S. P. Pissis, and L. Stougie. Differentially Private String Sanitization for Frequency-Based Mining Tasks.     IEEE International Conference on Data Mining (ICDM), 2021. Regular Paper. (code) 4. H. Chen, A. Conte, R. Grossi, G. Loukides, S. P. Pissis, and M. Sweering. On Breaking Truss-Based Communities.     ACM SIGKDD Conference on Knowledge Discovery and Data Mining (KDD), 2021. Research Track. (code) 5. C. Hu, Li, Z. Liu, X. Guo, Y. Wei, X. Guang, G. Loukides, and C. Dong. How to Make Private Distributed Cardinality Estimation Practical, and Get Differential Privacy for Free.     USENIX Security Symposium, 2021. (full version) 6. L. Zheng, H. Chan, G. Loukides, and M. Li. Maximizing Approximately k-Submodular Functions.     SIAM International Conference on Data Mining (SDM), 2021. (full version, code) 7. G. Bernardini, H. Chen, A. Conte, R. Grossi, G. Loukides, N. Pisanti, S. P. Pissis, G. Rosone, and M. Sweering. Combinatorial Algorithms for String Sanitization.     ACM Transactions on Knowledge Discovery from Data (TKDD), 2020. (code) 8. G. Bernardini, A. Conte, G. Gourdel, R. Grossi, G. Loukides, N. Pisanti, S. P. Pissis, G. Punzi, and L. Stougie, and M. Sweering. Hide and Mine in Strings: Hardness and Algorithms.     IEEE International Conference on Data Mining (ICDM), 2020. 9. C. Dong and G. Loukides. Approximating Private Set Union/Intersection Cardinality with Logarithmic Complexity.     IEEE Transactions on Information Forensics and Security, vol 12 (11), 2017. 10. G. Loukides and R. Gwadera. Optimal event sequence sanitization.     SIAM International Conference on Data Mining (SDM), 2015. 11. R. Gwadera, A. Gkoulalas-Divanis, and G. Loukides. Permutation-based Sequential Pattern Hiding.     IEEE International Conference on Data Mining (ICDM), 2013. (Acceptance rate for regular papers: 94/809≈11.6%)     [presentation, poster] 12. A. Gkoulalas-Divanis and G. Loukides. Revisiting Sequential  Pattern Hiding to Enhance Utility.     ACM SIGKDD Conference on Knowledge Discovery and Data Mining (KDD), 2011.  13. G. Loukides, A. Gkoulalas-Divanis, and B. Malin. Anonymization of Electronic Medical Records for Validating Genome-Wide Association Studies.      Proceedings of the National Academy of Sciences of the  United States of America, vol. 107 (17), 2010. (Impact Factor 9.83)      Acknowledged as one of the most  important technologies to improve the effectiveness of healthcare by a      National Human Genome Research Institute Nature publication

Selected Invited Talks

1. Heavy Nodes in a Small Neighborhood. Birbeck, University of London, 2023 & University of Trieste, Italy, 2022.
2. Combinatorial string dissemination. UK Cyber Security & Privacy Seminar Series (USPS), 2021.
3. String sanitization: a combinatorial approach. Laboratoire d'Informatique de l'Ecole Polytechnique, Paris, France, 2019 & University of Pisa, Italy, 2019.
4. Preventing string data from reconstruction. Cardiff University, Cardiff, UK, 2019.
5. Data Mining and Modelling as a Tool for Biosecurity. New approaches to gray zone threats, University of New South Wales (UNSW), Australia, 2018.
6. Privacy-preserving publication of complex data. Sensing and Privacy Workshop, Queen Mary University of London (QMUL), UK, 2017.
7. Anonymization of high-dimensional datasets, Isaac Newton Institute, Cambridge, UK, 2016.

Tutorials

1. Privacy-preserving Medical Data Sharing, SIAM International Conference on Data Mining (SDM) 2012, Anaheim, California, USA, 2012.
2. Privacy Challenges and Solutions for Medical Data Sharing, ECML/PKDD 2011, Athens, 2011.