Alexander Dobler successfully defended his PhD thesis “Algorithmic Aspects of Ordering Problems in Information Visualization” on December 11, 2025. Congratulations, Dr. Dobler!

Alexander was a PhD student in the Algorithms and Complexity Group and worked in the project Engineering Linear Ordering Algorithms for Optimizing Data Visualizations funded by WWTF. He was supervised by Martin Nöllenburg and his external thesis reviewers were Markus Chimani and Walter Didimo.

We are deeply saddened by the passing of Herbert Fleischner, friend and colleague. Herbert was a distinguished graph theorist whose work, including the famous Fleischner’s theorem, shaped the field. Read our full obituary here.

From September 24 to 26, the 33rd International Symposium on Graph Drawing and Network Visualization took place in Norrköping, Sweden. As every year, the conference hosted the Graph Drawing Contest, in which student teams from TU Wien participated in several categories as part of the Master course Graph Drawing Algorithms taught by Martin Nöllenburg.

In the creative contest, participants were given a network and asked to design an appealing visualization that also reveals interesting insights into the underlying data. This year’s topic centered on the Netflix series Dark: Nodes in the

The Parameterized Algorithms and Computational Experiments (PACE) Challenge takes place annually as part of the International Symposium on Parameterized and Exact Computation (IPEC) to deepen the relationship between parameterized algorithms and practice. The results of the 2025 iteration were presented in Warsaw, Poland, as part of  ALGO 2025 from September 15-19. PACE 2025 featured two classic algorithmic problems, Dominating Set and Hitting Set. In a total of four tracks, an exact as well as a heuristic one, practical solutions to these two NP-hard problems were solicited.

The solver submitted by Alexander

COMSOC 2025 Begins – Computational Social Choice

September 17–19, 2025 · TU Wien, Vienna, Austria

We are excited to host COMSOC 2025, the 10th interdisciplinary workshop in the Computational Social Choice series, at TU Vienna, from 17 to 19 September 2025. COMSOC brings together researchers, professionals, students, and newcomers from Economics, Political & Social Sciences, and Computer Science.
The workshop will cover topics such as voting & collective decision-making, fair division, judgement aggregation, opinion diffusion, participatory budgeting, matching and allocation, and more. Featured invited speakers include Moon Duchin (Cornell), Kurt Mehlhorn (MPI Saarbrücken),

Two papers co-authored by our ESPRIT fellow Sara Di Bartolomeo received awards during the EuroVis 2025 conference, held June 2-6 in Luxembourg. The Best Paper Award went to the paper “NODKANT: Exploring Constructive Network Physicalization” written by Sara together with her co-authors Daniel Paar, Henry Ehlers, Velitchko Filipov, Christina Stoiber, Wolfgang Aigner, Hsiang-Yun Wu, and Renata Raidou. This paper explores how constructing physical models of graph data can improve people’s understanding of complex information.

A second paper, “Optimizing Staircase Motifs in Biofabric Network Layouts​”, written by Sara Di Bartolomeo, Markus Wallinger,

Markus Wallinger, who did his PhD in the Algorithms and Complexity group in 2024, received the EuroVis PhD Award for his thesis “Exploring Graph-based Concepts for Balanced Information Density in Data Visualizations” last week during the EuroVis conference in Luxembourg. This year’s EuroVis PhD Award was awarded to three young researchers and recognizes outstanding dissertations in academic research and development on topics relevant to visualization. Markus’ thesis was supervised by Martin Nöllenburg and supported by the WWTF grant “Engineering Linear Ordering Algorithms for Optimizing Data Visualizations”. Markus is now a postdoctoral

Thomas Depian, Simon D. Fink, Alexander Firbas, Robert Ganian, and Martin Nöllenburg received the Best Paper Award for their paper Pathways to Tractability for Geometric Thickness [arXiv] at the 50th International Conference on Current Trends in Theory and Practice of Computer Science (SOFSEM) held in Bratislava, Slovakia from January 20-23, 2025.

Our former group member Markus Wallinger won the Award of Excellence by the Federal Ministry for Education, Science and Research. This state prize is awarded annually to 40 outstanding dissertations completed at all Austrian universities and in all subjects. Markus, as one of only four researchers of TU Wien, received this prestigious award on December 5, 2024 for his dissertation “Exploring Graph-based Concepts for Balanced Information Density in Data Visualizations”, supervised by Martin Nöllenburg. Markus is now a postdoctoral researcher at the Chair of Efficient Algorithms at TU Munich. Congratulations,

Our group member Thomas Depian won the Appreciation Award given by the Federal Ministry for Education, Science and Research. This state prize is awarded annually to the best 55 Master graduates among each year’s about 16.000 graduates of all Austrian universities. In 2024 Thomas, as one of only two students of TU Wien, received this prestigious award for his Master’s thesis “Grouping and Ordering Constraints in Boundary Labeling”, supervised by Martin Nöllenburg. Thomas will present the results of his thesis at the 35th International Symposium on Algorithms and Computation (ISAAC’24)