Category Archives: Student

Ane defends her PhD: Network analysis of Denmark’s bicycle infrastructure

Big congratulations to Dr. Ane Rahbek Vierø – she defended her thesis yesterday, on Network Analysis of Denmark’s Bicycle Infrastructure: Data & Infrastructure for All? 🥳 🎓 We are proud about Ane’s brilliant scientific accomplishments that have also started to have a big practical impact on bicycle network planning nationally and internationally.

Supervisor: Michael Szell
Committee: Michele Coscia, Trine Agervig Carstensen, Trivik Verma

Read her thesis here: https://en.itu.dk/Research/PhD-Programme/PhD-Defences/PhD-Defences-2025/May/Ane-Rahbek-Vier_

The thesis spans 5 papers that advance data and network analysis of bicycle infrastructure, from the 3 perspectives of 1) data foundations, 2) spatial patterns of bikeability, 3) linking research and planning. Unique achievements are the analysis of a whole country’s (Denmark’s) bicycle infrastructure and network, with the creation of open source tools. The thesis also concludes a project funded by the Danish Ministry of Transport / Road Directorate.

In her research Ane reveals that bicycle infrastructure data often suffer from inconsistencies and low quality, reflecting historical underinvestment in active mobility data. This data heterogeneity creates an information gap and necessitates extensive preprocessing, creating barriers to cycling research and planning. Additionally, she finds that bikeability and access to low-stress cycling infrastructure are highly spatially clustered, with substantial disparities between urban and rural areas. While urban areas generally benefit from better cycling conditions, large segments of the Danish population are deprived of the advantages of active mobility. The geographical differences in bicycle infrastructure access and data quality highlight the need for a spatial perspective in cycling research. Finally, she demonstrates that data-driven tools can aid bicycle planning by generating insights into complex planning questions that involve large geographical areas.

With her PhD completed, Ane has already started a research position at Roskilde University, where she remains at least for the short term. We are both sad to “lose” Ane with her friendly, collegial spirit and unreplaceable skill set, and happy for her success and positive impact in the world. That being said, we are not finished collaborating, and will always be happy to see Ane around.

Paper & Viz: Analysis of Denmark’s whole bicycle network

Today we published the paper which marks the Grand Finale of Ane’s PhD, which she will defend this thursday, May 22nd, in Auditorium 2 at ITU: https://en.itu.dk/Research/PhD-Programme/PhD-Defences/PhD-Defences-2025/May/Ane-Rahbek-Vier_

Her thesis is “Network Analysis of Denmark’s Bicycle Infrastructure: Data & Infrastructure for All?”, of which an important part is the paper:

Network Analysis of the Danish Bicycle Infrastructure: Bikeability Across Urban–Rural Divides, by A.R. Vierø and M. Szell, published in Geographical Analysis

To bridge the gap between urban and rural cycling research, we analyze the bicycle network of Denmark, covering around 43,000 km2 and nearly 6 million inhabitants. We divide the network into four levels of traffic stress and quantify the spatial patterns of bikeability based on network density, fragmentation, and reach. We find that the country has a high share of low-stress infrastructure, but with a very uneven distribution. The widespread fragmentation of low-stress infrastructure results in low mobility for cyclists who do not tolerate high traffic stress. Finally, we partition the network into bikeability clusters and conclude that both high and low bikeability are strongly spatially clustered. Our research confirms that in Denmark, bikeability tends to be high in urban areas. The latent potential for cycling in rural areas is mostly unmet, although some rural areas benefit from previous infrastructure investments. To mitigate the lack of low-stress cycling infrastructure outside urban centers, we suggest prioritizing investments in urban–rural cycling connections and encourage further research in improving rural cycling conditions.

With the paper comes an interactive visualization of the whole bicycle network of Denmark! Check it out at: bikenetwork.dk

This achievement also marks the conclusion of all our “deliverables” for the Vejdirektoratet grant by the Danish Ministry of Transport which financed Ane’s Phd.

If you are around ITU, don’t miss Ane’s defense on thursday!

Anastassia defends her PhD: Urban Data Science for Sustainable Mobility

Big congratulations to Dr. Anastassia Vybornova – she defended her thesis yesterday, on Urban Data Science for Sustainable Mobility! 🥳 🎓 This makes Anastassia the first PhD student who did their whole PhD journey at NERDS – about which we are especially proud, besides her brilliant scientific accomplishments.

Supervisor: Michael Szell
Committee: Luca Rossi, Malene Freudendal-Pedersen, Robin Lovelace

Read her thesis here: https://en.itu.dk/Research/PhD-Programme/PhD-Defences/PhD-Defences-2025/March/Anastassia-Vybornova

The thesis spans 8 papers that advance Urban Data Science, exploring how this emerging field can ethically support human mobility that is both environmentally and socially sustainable, through the two lenses of Data and Networks.

In her research she develops algorithms and pipelines for multi-purpose spatial network simplification, for data quality assessment and planning of bicycle networks and low-traffic neighborhoods, showcasing applications to various cities. Further, she outlines pathways for incorporating data ethics into computational approaches to spatial manifestations of social inequalities. Lastly, she investigates the impact of transportation infrastructure on social connections in cities, quantitatively corroborating that urban highways are barriers to social ties. Stemming from various interdisciplinary collaborations, the results of this thesis cover multiple conceptual levels of Urban Data Science, from open source software development and data quality assessment to transportation network planning and the intersection of social and spatial networks. Through these efforts, this thesis advances the emerging field of Urban Data Science, showcasing the field’s potential to make human mobility more sustainable.

With her PhD completed, Anastassia starts a postdoc position at SODAS with Roberta Sinatra, retaining a visiting affiliation at NERDS. Anastassia has been both a professional and social cornerstone of NERDS, so we are lucky we will keep seeing her around. 💜

Update April 4th 2025: The defense and time in Copenhagen made a lasting impact on our external examiner: https://www.robinlovelace.net/post/copenhagenize/

PhD Open Call 2025

The ITU-wide PhD Open Call 2025, deadline Feb 24th, is now open!  If your research overlaps with ours and you are interested, get in touch!

Either reach out directly to one of us, or use the student contact form on our students page, where you can also get inspiration for potential research projects. Most professors at NERDS are currently open to PhD supervision and have good ideas for possible PhD projects, so don’t hesitate to reach out. One of our past PhD students, Anastassia, has joined us previously through this call.

In Denmark, PhD students are employees, where both salary and working conditions are excellent. The NERDS group is a down-to-earth and fun place to be. Copenhagen is often named as the best city in the world to live in, and for good reasons. It’s world-renowned for food, beer, art, music, architecture, the Scandinavian “hygge”, and much more. In Denmark, parental leave is generous, and child-care is excellent and cheap.

Student promotions

We have two student promotions to celebrate 🎉

First, Elisabetta Salvai has become a PhD student on Jan 1st 2025 at SODAS and the AI Pioneer Centre, supervised by Roberta Sinatra, after having visited us for many months. Her work centers around applying complex systems methods to uncover and explore bias existing in data and machine learning algorithms. She is currently working on the study of fairness in rankings of networks with binary attributes.

She will continue to visit us regularly. Congratulations Betta!

Second, Anastassia Vybornova has submitted her PhD Thesis by Dec 31st 2024, and since Jan 1st 2025 she is formally Postdoc with us for 3 more months until her PhD defense end of March. So, the real celebration for her will be then, but it is nice that she stays with us for 3 more months. In this time, Anastassia keeps finishing up some bicycle network and sustainable mobility papers.

Anders Aagaard Kristensen has joined NERDS

At NERDS we welcome our latest member: Anders Aagaard Kristensen!

Anders joins us as PhD student, coming from the University of South Denmark, where he was working on machine learning methods.

His PhD project will be about the use of deep learning and generative models to understand leaves of absence in work data. The idea is to predict, simulate and, ultimately, make interventions, so that workers will have less taxing working schedules, leading to fewer leaves for sickness reasons.

Anders will be working jointly with NERDS and the National Research Center for Work Environment (NFA), which finances his fellowship and provides the data. He will be supervised by Michele Coscia at NERDS.

NERDS at the D3A Conference

NERDS group made a strong return to the second edition of the D3A conference, held in Nyborg. Our presence across the sessions was extensive, starting from Toine welcoming us in the opening session.

The workshop “Networks, Data, Society, and AI”, organized by Vedran, Lasse, Anders, Anders, and Arianna, sparked inspiring dialogue on AI’s impact on society from diverse perspectives, and brought together an eclectic mix of speakers from industry, academia, and journalism.

Anastassia co-led the workshop “From Classroom to Career: Data Science Degrees and Early Career Opportunities,” which provided valuable guidance for young data scientists navigating the transition from academic studies to professional paths. (We were especially pleased to see Luca as one of the invited speakers here, adding an extra point of view to the session!)

Clément contributed a visually engaging poster on urban bicycle network planning, sparking plenty of conversations about sustainable city design. Mesut shared his latest research on fair recommendations in job markets in the “Fair Division – Economics, Computational Social Science, and AI” session.

All in all, this year’s D3A conference was a fantastic blend of intellectual exchange, practical workshops, and community building. It’s exciting to see the role NERDS is playing in these developments, and we’re already looking forward to bringing even more insights to next year’s event!

Carlson Büth wins VCD Award for his Master thesis

Carlson Moses Büth, who visited us last year from University of Münster, Germany, won the VCD Award (1st place Special Award) for his master thesis

From Gridlocks to Greenways: Analyzing the Network Effects of Computationally Generated Low Traffic Neighborhoods

that he wrote at ITU, co-supervised by Anastassia+Michael@NERDS. We congratulate Carlson to this achievement! 🎉


Photos from the VCD Award Ceremony by Jan Zappner

The VCD is the “Verkehrsclub Deutschland”, a major non-profit association and traffic club in Germany that is committed to a socially and environmentally friendly transport transition towards mobility for all road users.

Over the course of his master thesis Carlson also initiated the development of the Python package superblockify which we published recently within the JUST STREETS EU Horizon project we are part of. See: superblockify.city, its Github repository, and the accompanying paper at JOSS.

NERDS at ASONAM’24

A bunch of nerds posing in front of the asonam conference logoLuigi Arminio wins the asonam best phd dissertation award

NERDS’ summer sheneanigans continue at ASONAM, in the beautiful and sunny Calabria. Lucio La Cava and Alessia Galdeman held a tutorial on Mining, Modeling, and Analyzing Decentralized Social Media. Alessia Antelmi organized the HyperSci workshop on Theory and Applications of Hypernetwork Science. Luigi Arminio and Daniele De Vinco presented at the PhD Forum. Luca Aiello fulfilled his duties as the conference Program Chair. Luigi won the prize for the best PhD forum contribution!

Welcome Lasse, the latest NERDS PhD Student!

NERDS keeps growing! This month we’re welcoming Lasse Alsbirk as our latest addition to the team!

Lasse is a co-financed PhD student and at the center of a multi-partnered research project! He will work at the intersection of the Danish Police (financial crimes section), the AI Pioneer Center, and NERDS @ ITU. His project will focus on the application and development of network science tools to fight financial crimes. He has valuable abroad experience, having received his master degree in Israel and he will be with us for four years.

Welcome, Lasse!