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Dr. Pascal Welke


I am interested in Data Mining, Applied Graph Theory, Machine Learning, and Human-computer Interaction. I wrote my PhD thesis on 'Probabilistic Frequent Subtree Mining'.

I also teach several courses that are offered by our group in the Bachelors program and Masters program in Computer Science and I supervise BA and MA theses.


University of Bonn:

Room 1.027, Endenicher Allee 19a, 53115 Bonn. Phone: +49 228 73 4514

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I have an account on ResearchGate.  My publications are indexed by dblp.
You can give me anonymous feedback (for example on my teaching performance).


  1. Dario Antweiler, Pascal Welke:
    Temporal Graph Analysis for Outbreak Pattern Detection in COVID-19 Contact Tracing Networks.
    Machine Learning in Public Health Workshop, MLPH@NeurIPS, 2020 (accepted).

    [preprint] [slides] [workshop]

  2. Pascal Welke:
    Efficient Frequent Subgraph Mining in Transactional Databases.
    IEEE International Conference on Data Science and Advanced Analytics, DSAA, 2020.

    [preprint] [video] [slides] [doi] [conference]

  3. Pascal Welke, Fouad Alkhoury, Christian Bauckhage, Stefan Wrobel:
    Decision Snippet Features.
    International Conference on Pattern Recognition, ICPR, (accepted), 2021.

    [preprint] [doi] [conference]

  4. Pascal Welke, Florian Seiffarth, Michael Kamp, Stefan Wrobel:
    HOPS: Probabilistic Subtree Mining for Small and Large Graphs.
    ACM SIGKDD International Conference on Knowledge Discovery & Data Mining, KDD, 2020.

    [preprint] [short video] [slides] [video] [doi] [dblp] [conference]

  5. Alexander Mehler, Wahed Hemati, Pascal Welke, Maxim Konca, Tolga Uslu:
    Multiple Texts as a Limiting Factor in Online Learning: Quantifying (Dis-)similarities of Knowledge Networks across Languages.
    Frontiers in Education | Digital Education, 2020.

    [preprint] [doi] [dblp] [arXiv] [journal]

  6. Till Schulz, Pascal Welke:
    On the Necessity of Graph Kernel Baselines.
    Graph Embedding and Mining Workshop, GEM@ECMLPKDD 2019

    [paper] [poster] [workshop]

  7. Pascal Welke:
    Frequent Subtree Mining Beyond Forests.
    Dissertations in Artificial Intelligence Vol. 348, IOS Press, 2019

    [book] [pdf] [slides] [urn] [official publication venue]

  8. Pascal Welke, Tamas Horvath, Stefan Wrobel:
    Probabilistic and Exact Frequent Subtree Mining in Graphs Beyond Forests.
    Machine Learning, Volume 108, Issue 7, 2019

    [preprint] [doi] [read-only free official version] [journal]

  9. Pascal Welke, Tamas Horvath, Stefan Wrobel:
    Probabilistic Frequent Subtrees for Efficient Graph Classification and Retrieval.
    Machine Learning, Volume 107, Issue 11, Springer 2018.

    [preprint] [dblp] [doi] [read-only free official version] [journal]

  10. Till Hendrik Schulz, Tamas Horvath, Pascal Welke, Stefan Wrobel:
    Mining Tree Patterns with Partially Injective Homomorphisms.
    European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases, ECML/PKDD 2018, Springer LNCS 11052.

    [preprint] [slides] [dblp] [doi] [conference]

  11. Pascal Welke, Alexander Markowetz, Torsten Suel, Maria Christoforaki:
    3-Hop Distance Estimation in Social Graphs.
    IEEE International Conference on Big Data, BigData 2016, IEEE 2016.

    [preprint] [slides] [dblp] [doi] [conference]

  12. Pascal Welke, Tamas Horvath, Stefan Wrobel:
    Min-Hashing for Probabilistic Frequent Subtree Feature Spaces.
    Proceedings of Discovery Science - 18th International Conference, DS 2016, Springer LNAI 9956.

    [preprint] [slides] [poster] [dblp] [doi] [conference]

  13. Katrin Ullrich, Jennifer Mack, Pascal Welke:
    Ligand Affinity Prediction with Multi-Pattern Kernels.
    Proceedings of Discovery Science - 18th International Conference, DS 2016, Springer LNAI 9956.

    [preprint] [slides] [dblp] [doi] [conference]

  14. Pascal Welke, Ionut Andone, Konrad Blaskiewicz, Alexander Markowetz:
    Differentiating Smartphone Users by App Usage.
    Proceedings of the ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp 2016, ACM 2016.

    [preprint] [slides] [dblp] [doi] [conference]

  15. Pascal Welke, Tamas Horvath, Stefan Wrobel:
    Probabilistic Frequent Subtree Kernels.
    Proceedings of the Fourth Workshop on New Frontiers in Mining Complex Patterns, nfMCP 2015, Selected Extended Papers, Springer LNCS 9607.

    [preprint] [slides] [dblp] [doi] [workshop]

  16. Pascal Welke:
    Simple Necessary Conditions for the Existence of a Hamiltonian Path with Applications to Cactus Graphs.
    CoRR abs/1709.01367.

    [preprint] [slides] [arXiv] [workshop]

  17. Pascal Welke, Tamas Horvath, Stefan Wrobel:
    On the Complexity of Frequent Subtree Mining in Very Simple Structures.
    Proceedings of the Inductive Logic Programming Conference, ILP 2014, Springer LNCS 9046.

    [preprint] [slides] [dblp] [doi] [conference]

  18. Anne-Kathrin Mahlein, Till Rumpf, Pascal Welke, Heinz-Wilhelm Dehne, Lutz Plümer, Ulrike Steiner, Erich-Christian Oerke:
    Development of spectral indices for detecting and identifying plant diseases.
    Remote Sensing of Environment Volume 128, Elsevier 2013.

    [doi] [journal]

Community Activities

  1. I am Co-Organizing GEM'20, Workshop on Graph Embedding and Mining, collocated with ECMLPKDD'20. Looking forward to see you there!
  2. I am Program Chair (with Nico Piatkowski) of the KDML track at LWDA 2020. I hope to see you there!
  3. Member of the Program Committee of PDFL'20, the Workshop on Parallel, Distributed, and Federated Learning, collocated with ECMLPKDD'20. See you there!
  4. Program Committee Member of AISTATS'21, SDM'21, ICDM'20, ECMLPKDD'20, reviewer for NeurIPS'20
  5. Member of the Program Committee of GEM'19, the Workshop on Graph Embedding and Mining, collocated with ECMLPKDD'19.
  6. Member of the Program Committee of DMLE'19, the Second Workshop on Distributed Machine Learning at the Edge, collocated with ECMLPKDD'19.
  7. Reviews for several journals and conferences, e.g. Machine Learning, AMAI, ACM SIGKDD 2016, AISTATS 2020.
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