Research Portfolio

My research addresses new data science and machine learning methods that help us to understand collective behavior in complex systems with many interacting elements. My approach is quantitative, interdisciplinary, and data-driven, combining methods from machine learning, statistical modelling, graph theory, and the physics of complex systems.

Foundations of Network Science and Graph Learning

My group advances theoretical foundations of network science, graph learning and visualization. Exemplary contributions include:

A specific focus of my work is to understand how temporal interaction patterns influence the causal topology of complex systems, i.e. which elements can directly or indirectly influence each other. Over the past years, my group used these insights to develop causality-aware graph learning methods:

Applications in biological, physical, and social systems

Apart from foundational works on artificial intelligence, my group applies these methods to answer open questions in biology, physics, social science, humanities, and engineering, such as:

  • How do interactions between cells in biological tissue influence gene expression? [learn more]
  • How do collaboration structures in software teams influence the productivity of developers? [learn more]
  • How do temporal collaboration patterns of developers influence the success and failure of Open Source Communities? [learn more]
  • How can we monitor and improve the evolution of complex software architectures? [learn more]
  • How do collaboration patterns influence the success of scientists? [learn more]
  • What insights can deep learning provide on the structure of school curricula? [learn more]
  • How can we use computational methods to analyze narrative structures in literature? [learn more]
  • How can deep learning speed up computationally expensive simulations in plasma physics?

I have published in top-tier interdisciplinary journals such as Nature Physics, Nature Communications, and Physical Review Letters, as well as in A* computer science venues like ICSE, SIGKDD, The Web Conference, and NeurIPS.

Third-party Funded Projects

My research in the areas outlined above was selected for major funding awards with a volume of more than 3.2 mio EUR.

Software, Tools, and Technology Transfer

My group actively engages in the transfer of our research into practice, developing open source software and tools that help researchers as well as practitioners from industry.

  • I am creator of the Open Source temporal graph learning package pathpyG, which is actively developed in my group. It facilitates GPU-accelerated causality-aware deep learning in time series data on complex networks.
  • In the context of our third-party funded project Software Campus 3.0, we work with an industry partner to develop the online analytics platform gitBoard, which provides an AI-based early warning of organizational risks in large software development projects, thus helping to mitigate risks in software supply chains.
  • With Dr. Christoph Gote, I created the Open Source data mining package git2net. It allows to use open data from git repositories to infer fine-grained temporal interaction networks between software developers. The package received a Special Mention in the Free and Open Source Software (FOSS) Impact Paper Award.
  • From 2004 to 2008 I was developer of the Event Monitoring Service (Emon), a large-scale data distribution system that is currently used to analyze particle collision data from the ATLAS detector at CERN's Large Hadron Collider Experiment.