#Knoflacher: „Der Mobilitätsbegriff ist bis heute falsch definiert, weil er mit dem Autofahren verwechselt wird. Dabei ist man im Auto völlig immobil, da hockt man wie ein Affe am Schleifstein. Das hat nichts mit Mobilität zu tun.“ 👏🚲💚
#Verkehrswende
https://www.derstandard.de/story/3000000268424/verkehrsforscher-knoflacher-im-auto-hockt-man-wie-ein-affe-am-schleifstein

"The Copilot Delusion" by Jj https://deplet.ing/the-copilot-delusion/

"You’re not working with a copilot. You’re playing Russian roulette with a loaded dependency graph."

Infinitely quotable. I wish I could write like this.

In the last 2 months, 2 of my brilliant 🚲 PhD students have graduated.
https://nerds.itu.dk/2025/05/23/ane-defends-her-phd-network-analysis-of-denmarks-bicycle-infrastructure/
https://nerds.itu.dk/2025/04/01/anastassia-defends-her-phd-urban-data-science-for-sustainable-mobility/

Feeling proud, sad, happy, all at the same time.

Ane defends her PhD: Network analysis of Denmark’s #bicycle infrastructure
https://nerds.itu.dk/2025/05/23/ane-defends-her-phd-network-analysis-of-denmarks-bicycle-infrastructure/
Congrats to @ane ! 🎉

Are groundbreaking science discoveries becoming harder to find?
https://www.nature.com/articles/d41586-025-01548-4
Interesting article featuring our @robysinatra

@jroper there are a lot of academics on Bsky, but to see more happening here one also needs to follow enough people and hashtags, then it works pretty well. Bsky is quite US/daily news centric, so I don't get much out of it. +I have seen Bsky described as committing to a pet that you know will die in a few years (similar fate as twitter, due to being centralized, VC funded, etc). Mastodon is quieter but more organic and genuine, and I expect it will more likely last in the long term.

Paper & Viz: Analysis of Denmark’s whole bicycle network
https://nerds.itu.dk/2025/05/20/paper-viz-analysis-of-denmarks-whole-bicycle-network/

Call for papers! A special issue on Open Urban Data Science in CEUS, edited by Filip Biljecki, @gboeing, @hugoledoux, and me, is now accepting submissions. We are looking for full-length papers on open software tools around spatial data science, cities, and related topics. Submissions are treated as single-blinded, so you can include all the links to public repositories. More details at the journal site - https://www.sciencedirect.com/special-issue/322127/open-urban-data-science. If you have any questions, I’m happy to answer!

And obviously it is absolutely brilliant what Paris was able to achieve so far in such a short time!! I can't wait to visit at some point and experience it myself. So, apart from the "naming and shaming", we also need more "naming and praising".

On the technical level my point is simply that it is very hard to directly compare cities when the underlying data are of unreliable quality.

Promoting walking and cycling: a toolkit of policy options
https://www.who.int/publications/i/item/9789240109902

Old music that sounds contemporary is so fascinating. Here Alkan or Ligeti for example.
Alkan (1840 🤯): https://youtu.be/rQ81jzlR1y4?si=8Avifn4b03Y_YmSl&t=336
Ligeti (1952): https://www.youtube.com/watch?v=oXsRlMneOS0

If anyone knows more, especially in this "8-bit video game music" style, please comment below - I'd love to know about it!

“Vehicles with higher, more vertical front ends pose greater risk to pedestrians. Vehicles with especially tall front ends are most dangerous to pedestrians, but a blunt profile makes medium-height vehicles deadly too.” Deadly by design. And they know it. www.iihs.org/news/detail/...

The deal breaker theory of cycling: A new approach to understanding bike behavior
https://www.sciencedirect.com/science/article/pii/S2590198225001411
Interesting. I always thought of it in terms of Liebig's law of the minimum (https://en.wikipedia.org/wiki/Liebig%27s_law_of_the_minimum), which is almost the same idea.

@antoniovr Yes, it is nice that things *are* happening, but it's way too slow. Also, I personally live in FRB, just on the border, and FRB just doesn't care: 100m from my home all speed limits decreased but in front of my home FRB keeps 50km/h 😠
This needs a bold national (better: European) legislative solution, not all kommunen doing their own thing..

I've read now through the "Streets for kids" #cityranking report: https://cleancitiescampaign.org/city-ranking-2025/
#copenhagen isn't even in the top 10 for child mobility among 36 major European cities. The bad ranking is deserved: Despite a good bicycle network, there are barely any school streets or safe speed limits (30km/h). Overall, Danish politicians just seem to care less about children 👎🚸 ..and they do love cars & highways 😍🚙🇩🇰
Caveats:..

..This year's reduction by 10km/h on all CPH streets isn't yet accounted for. While most streets are still at unacceptable 40+km/h, some more have become 30km/h.
Further, working myself with both Paris and CPH data, I did really not understand how they think Paris is leading in protected bicycle infrastructure. Digging into the data they offer for download reveals that most data were provided by the cities. So, Paris says 48% of their road network is protected bicycle infra. 🤨???..

..This doesn't make sense. I assume Paris counts 30km/h streets as protected bike infra? -would be questionable and redundant with the speed metric.👎

All in all, I think such reports are very important, to "name and shame" politicians for how much they are neglecting children (and as a consequence: everyone). The report is very nicely explaining and visualizing. Relying on data provided by cities is just not trustworthy, sorry. So, great effort, but dubious outcome due to low data quality.

Congrats on the EU petition against conversion practices reaching 1M! 🎉 Impressive finish.

While we are signing EU petitions, this one on #airQuotas looks important/interesting, to limit flying: https://eci.ec.europa.eu/051/public/#/screen/home

995365 signatures to go until December. Go!

Paris now the safest European cycling city for kids, with three UK cities making the top 20
https://www.bikeradar.com/news/paris-now-the-safest-european-cycling-city-for-kids
French capital topples Amsterdam from the top spot following investment in cycling infrastructure.

None UK cities is in Scotland, we are getting left behind...

Just published in JOSS: 'ParquetDB: A Lightweight Python Parquet-Based Database' https://doi.org/10.21105/joss.07932