Panagiotis Karras

Department of Computer Science
Aarhus University
Åbogade 34
Aarhus, Denmark 8200
panos at cs au dk


Panagiotis Karras is an Associate Professor in Computer Science at Aarhus University.

In his research he designs robust and versatile methods for data access, mining, and representation.

He received an MEng in Electrical and Computer Engineering from the National Technical University of Athens, a PhD in Computer Science from the University of Hong Kong, and the 2008 Young Scientist Award in Physical/Mathematical Science from HKIS.

In the past he has held positions at Aalborg University, Skoltech, Rutgers, NUS, UZH, and DTU.



Refereed Conference and Journal Articles

  1. VERSE: Versatile Graph Embeddings from Similarity Measures
    Anton Tsitsulin, Davide Mottin, Panagiotis Karras, and Emmanuel Müller
    Proc. of the 27th Intl World Wide Web Conf. (WWW), Lyon, France, April 2018

  2. Content Recommendation for Viral Social Influence
    Sergei Ivanov, Konstantinos Theocharidis, Manolis Terrovitis, and Panagiotis Karras
    Proc. of the 40th ACM SIGIR Intl Conf. on Research and Development in Information Retrieval (SIGIR), Tokyo, Japan, August 2017

  3. Indoor Localization Accuracy Estimation from Fingerprint Data
    Artyom Nikitin, Christos Laoudias, Georgios Chatzimilioudis, Panagiotis Karras, and Demetrios Zeinalipour-Yazti
    Proc. of the 18th IEEE Intl Conf. on Mobile Data Management (MDM), Daejeon, South Korea, May 2017

  4. Harvester: Influence Optimization in Symmetric Interaction Networks
    Sergei Ivanov and Panagiotis Karras
    Proc. of the 3rd IEEE Intl Conf. on Data Science and Advanced Analytics (DSAA), Montreal, Canada, October 2016

  5. Adaptive Indexing over Encrypted Numeric Data
    Panagiotis Karras, Artyom Nikitin, Muhammad Saad, Rudrika Bhatt, Denis Antyukhov, Stratos Idreos
    Proc. of the 2016 ACM SIGMOD Intl Conf. on Management of Data (SIGMOD), San Francisco, California, June 2016

  6. TRANSFORMERS: Robust spatial joins on non-uniform data distributions
    Mirjana Pavlovic, Thomas Heinis, Farhan Tauheed, Panagiotis Karras, and Anastasia Ailamaki
    Proc. of the 32nd IEEE Intl Conf. on Data Engineering (ICDE), Helsinki, Finland, May 2016

  7. Fuzzy trajectory linking
    Huayu Wu, Mingqiang Xue, Jianneng Cao, Panagiotis Karras, Wee Siong Ng, and Kee Kiat Koo
    Proc. of the 32nd IEEE Intl Conf. on Data Engineering (ICDE), Helsinki, Finland, May 2016

  8. Collaborative Search Log Sanitization: Toward Differential Privacy and Boosted Utility
    Yuan Hong, Jaideep Vaidya, Haibing Lu, Panagiotis Karras, and Sanjay Goel
    IEEE Transactions on Dependable and Secure Computing (TDSC), 12(5), 2015

  9. k-Anonymization by Freeform Generalization
    Katerina Doka, Mingqiang Xue, Dimitrios Tsoumakos, and Panagiotis Karras
    Proc. of the 10th ACM Symposium on Information, Computer and Communications Security (AsiaCCS), Singapore, April 2015

  10. An Equitable Solution to the Stable Marriage Problem
    Ioannis Giannakopoulos, Panagiotis Karras, Dimitrios Tsoumakos, Katerina Doka, Nectarios Koziris
    Proc. of the 27th IEEE Intl Conf. on Tools with Artificial Intelligence (ICTAI), Vietri sul Mare, Italy, November 2015

  11. Graph-Aware, Workload-Adaptive SPARQL Query Caching
    Nikolaos Papailiou, Dimitrios Tsoumakos, Panagiotis Karras, and Nectarios Koziris
    Proc. of the 2015 ACM SIGMOD Intl Conf. on Management of Data (SIGMOD), Melbourne, Australia, June 2015

  12. L-opacity: Linkage-Aware Graph Anonymization
    Sadegh Nobari, Panagiotis Karras, HweeHwa Pang, and Stéphane Bressan
    Proc. of the 17th Intl Conf. on Extending Database Technology (EDBT), Athens, Greece, March 2014

  13. On the Privacy and Utility of Anonymized Social Networks
    Yi Song, Xuesong Lu, Sadegh Nobari, Stéphane Bressan, and Panagiotis Karras
    International Journal of Adaptive, Resilient and Autonomic Systems (IJARAS), 4(2), 2013

  14. An effective and efficient parallel approach for random graphs generation over GPUs
    Stéphane Bressan, Alfredo Cuzzocrea, Panagiotis Karras, Xuesong Lu, and Sadegh Nobari
    Journal of Parallel and Distributed Computing (JPDC), 73(3), March 2013

  15. H2RDF+: High-performance Distributed Joins over Large-scale RDF Graphs
    Nikolas Papailiou, Ioannis Konstantinou, Dimitrios Tsoumakos, Panagiotis Karras, and Nectarios Koziris
    Proc. of the 2013 IEEE Intl Conf. on Big Data (IEEE BigData), Santa Clara, California, October 2013

  16. eSkyline: Processing Skyline Queries over Encrypted Data
    Suvarna Bothe, Panagiotis Karras, and Akrivi Vlachou
    Proc. of the 39th Intl Conf. on Very Large Data Bases (VLDB), Riva del Garda, Italy, August 2013

  17. TOUCH: In-Memory Spatial Join by Hierarchical Data-Oriented Partitioning
    Sadegh Nobari, Farhan Tauheed, Thomas Heinis, Panagiotis Karras, Stéphane Bressan, and Anastasia Ailamaki
    Proc. of the 2013 ACM SIGMOD Intl Conf. on Management of Data (SIGMOD), New York, NY, June 2013

  18. Publishing Microdata with a Robust Privacy Guarantee
    Jianneng Cao and Panagiotis Karras
    Proc. of the VLDB Endowment (PVLDB), 5(11), July 2012 (38th VLDB Conf., Istanbul, August 2012)

  19. Stochastic Database Cracking: Towards Robust Adaptive Indexing in Main-Memory Column-Stores
    Felix Halim, Stratos Idreos, Panagiotis Karras, and Roland H. C. Yap
    Proc. of the VLDB Endowment (PVLDB), 5(6), February 2012 (38th VLDB Conf., Istanbul, August 2012)

  20. Delineating Social Network Data Anonymization via Random Edge Perturbation
    Mingqiang Xue, Chedy Raïssi, Panagiotis Karras, Panos Kalnis, and Hung Keng Pung
    Proc. of the 21st ACM Conf. on Information and Knowledge Management (CIKM), Maui, Hawaii, October 2012

  21. Discretionary Social Network Data Revelation with a User-Centric Utility Guarante
    Song Yi, Panagiotis Karras, Sadegh Nobari, Giorgos Cheliotis, Mingqiang Xue, and Stéphane Bressan
    Proc. of the 21st ACM Conf. on Information and Knowledge Management (CIKM), Maui, Hawaii, October 2012

  22. Anonymizing Set-Valued Data by Nonreciprocal Recoding
    Mingqiang Xue, Panagiotis Karras, Chedy Raïssi, Jaideep Vaidya, and Kian-Lee Tan
    Proc. of the 18th ACM SIGKDD Intl Conf. on Knowledge Discovery and Data Mining (KDD), Beijing, China, August 2012

  23. Cooperative Scalable Moving Continuous Query Processing
    Xiaohui Li, Panagiotis Karras, Lei Shi, Kian-Lee Tan, and Christian S. Jensen
    Proc. of the 13th IEEE Intl Conf. on Mobile Data Management (MDM), Bengaluru, India, July 2012

  24. Sensitive Label Privacy Protection on Social Network Data
    Yi Song, Panagiotis Karras, Qian Xiao, and Stéphane Bressan
    Proc. of the 24th Intl Conf. on Scientific and Statistical Database Management (SSDBM), Chania, Crete, Greece, June 2012

  25. Scalable Parallel Minimum Spanning Forest Computation
    Sadegh Nobari, Thanh-Tung Cao, Panagiotis Karras, and Stéphane Bressan
    Proc. of the 17th ACM SIGPLAN Symp. on Principles and Practice of Parallel Programming (PPoPP), New Orleans, Louisiana, February 2012

  26. Authenticated Multi-Step Nearest Neighbor Search
    Stavros Papadopoulos, Lixing Wang, Yin Yang, Dimitris Papadias, and Panagiotis Karras
    IEEE Transactions on Knowledge and Data Engineering (TKDE), 23(5), May 2011

  27. SABRE: A Sensitive Attribute Bucketization and REdistribution framework for t-closeness
    Jianneng Cao, Panagiotis Karras, Panos Kalnis, and Kian-Lee Tan
    The VLDB Journal (VLDBJ), 20(1), February 2011

  28. Utility-Driven Anonymization in Data Publishing
    Mingqiang Xue, Panagiotis Karras, Chedy Raïssi, and Hung Keng Pung
    Proc. of the 20th ACM Conf. on Information and Knowledge Management (CIKM), Glasgow, United Kingdom, October 2011

  29. Scalable kNN Search on Vertically Stored Time Series
    Shrikant Kashyap and Panagiotis Karras
    Proc. of the 17th ACM SIGKDD Intl Conf. on Knowledge Discovery and Data Mining (KDD), San Diego, California, August 2011

  30. Fast Random Graph Generation
    Sadegh Nobari, Xuesong Lu, Panagiotis Karras, and Stéphane Bressan
    Proc. of the 14th Intl Conf. on Extending Database Technology (EDBT), Uppsala, Sweden, March 2011

  31. ρ-uncertainty: Inference-Proof Transaction Anonymization
    Jianneng Cao, Panagiotis Karras, Chedy Raïssi, and Kian-Lee Tan
    Proc. of the VLDB Endowment (PVLDB), 3(1) (36th VLDB Conf., Singapore, September 2010)

  32. CW2I: Community Data Indexing for Complex Query Processing
    Mei Hui, Panagiotis Karras, and Beng Chin Ooi
    Proc. of the 11th Intl Conf. on Web-Age Information Management (WAIM), Jiuzhaigou, China, July 2010

  33. Local Search in Histogram Construction
    Felix Halim, Panagiotis Karras, and Roland H. C. Yap
    Proc. of the 24th AAAI Conf. on Artificial Intelligence (AAAI), Atlanta, Georgia, July 2010

  34. Optimality and Scalability in Lattice Histogram Construction
    Panagiotis Karras
    Proc. of the VLDB Endowment (PVLDB), 2(1) (35th VLDB Conf., Lyon, France, August 2009)

  35. A Framework for Efficient Data Anonymization under Privacy and Accuracy Constraints
    Gabriel Ghinita, Panagiotis Karras, Panos Kalnis, and Nikos Mamoulis
    ACM Transactions on Data Base Systems (TODS), 34(2), June 2009

  36. Fast and Effective Histogram Construction
    Felix Halim, Panagiotis Karras, and Roland H. C. Yap
    Proc. of the 18th ACM Conf. on Information and Knowledge Management (CIKM), Hong Kong, China, November 2009

  37. Multiplicative Synopses for Relative-Error Metrics
    Panagiotis Karras
    Proc. of the 12th Intl Conf. on Extending Database Technology (EDBT), Saint-Petersburg, Russia, March 2009

  38. Hexastore: Sextuple Indexing for Semantic Web Data Management
    Cathrin Weiss, Panagiotis Karras, and Abraham Bernstein
    Proc. of the VLDB Endowment (PVLDB), 1(1) (34th VLDB Conf., Auckland, New Zealand, August 2008)

  39. Hierarchical Synopses with Optimal Error Guarantees [appendix]
    Panagiotis Karras and Nikos Mamoulis
    ACM Transactions on Data Base Systems (TODS), 33(3), August 2008

  40. Lattice Histograms: a Resilient Synopsis Structure
    Panagiotis Karras and Nikos Mamoulis
    Proc. of the 24th IEEE Intl Conf. on Data Engineering (ICDE), Cancún, Mexico, April 2008

  41. Common Influence Join: A Natural Join Operation for Spatial Pointsets
    Man Lung Yiu, Nikos Mamoulis, and Panagiotis Karras
    Proc. of the 24th IEEE Intl Conf. on Data Engineering (ICDE), Cancún, Mexico, April 2008

  42. Ring-constrained Join: Deriving Fair Middleman Locations from Pointsets via a Geometric Constraint
    Man Lung Yiu, Panagiotis Karras, and Nikos Mamoulis
    Proc. of the 11th Intl Conf. on Extending Database Technology (EDBT), Nantes, France, March 2008

  43. Fast Anonymization with Low Information Loss
    Gabriel Ghinita, Panagiotis Karras, Panos Kalnis, and Nikos Mamoulis
    Proc. of the 33rd Intl Conf. on Very Large Data Bases (VLDB), Vienna, September 2007

  44. Exploiting Duality in Summarization with Deterministic Guarantees
    Panagiotis Karras, Dimitris Sacharidis, and Nikos Mamoulis
    Proc. of the 13th ACM SIGKDD Intl Conf. on Knowledge Discovery and Data Mining (KDD), San Jose, California, August 2007

  45. The Haar+ Tree: a Refined Synopsis Data Structure
    Panagiotis Karras and Nikos Mamoulis
    Proc. of the 23rd IEEE Intl Conf. on Data Engineering (ICDE), Istanbul, April 2007

  46. Detecting the Direction of Motion in a Binary Sensor Network
    Panagiotis Karras and Nikos Mamoulis
    Proc. of the 1st IEEE Intl Conf. on Sensor Networks, Ubiquitous, and Trustworthy Computing (SUTC), Taichung, June 2006

  47. One-Pass Wavelet Synopses for Maximum-Error Metrics
    Panagiotis Karras and Nikos Mamoulis
    Proc. of the 31st Intl Conf. on Very Large Data Bases (VLDB), Trondheim, Norway, August 2005

Teaching

    29:623:375: Computer Network Applications (Spring 2013)
    26:198:641: Advanced Database Systems (Fall 2012)
    26:198:643: Information Security (Spring 2012)
    29:623:220: Management Information Systems (Spring 2012)
    22:198:603: Business Data Management (Fall 2011, Fall 2012, Fall 2013 Nwk, Fall 2013 NB)
    29:623:350: Structured Programming Applications (Fall 2011, Spring 2013)
    CS5322: Database Security (Spring 2010)
    CS3230: Design and Analysis of Algorithms (Fall 2009)
    CS6234: Advanced Algorithms (Spring 2009)
    CS2102: Database Systems (Spring 2009, Fall 2009)

Service

    Journal Referee for:
    Journal of the ACM, Algorithmica, ACM TODS, VLDB Journal, Distributed and Parallel Databases, Knowledge and Information Systems, IEEE TKDE, Information Systems, Information Sciences, DKE, Data Mining and Knowledge Discovery, Pattern Recognition Letters, Pervasive and Mobile Computing, International Journal of Data Warehousing and Mining, Journal of Computing Science and Engineering, Journal of Zhejiang University

    Program Committee Memberships:
    2014: VLDB, EDBT (Demonstrations Track), CAiSE, DASFAA
    2013: SIGMOD, CIKM, ICDM, BigData, ECMLPKDD, PAKDD, WISE, SSTD, DaWaK, DATA, ANT, STAKE, INTELLI, EIDWT, PADM, MEDI
    2012: KDD, ICDE, ECMLPKDD, CAiSE, PAKDD, WISE, WebDB, DaWaK, AP-Cloud, PinSoDa, INTELLI, DATA, ADMA
    2011: KDD, EDBT, ECMLPKDD, CAiSE, PAKDD, WISE, ESWC, DaWaK, CISIS, STAKE, ADMA, ADBIS, IDEAS
    2010: VLDB, CIKM, ECMLPKDD, ICDE PhD Workshop, PAKDD, WISE, UMMM, APSIPA, CISIS, ADBIS, SemData@VLDB
    2009: ICDE (Demonstrations Track), PAKDD