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YY Ahn

@yyahn

Prof @ School of Data Science, University of Virginia. Formerly at IU. Networks, data science, and machine learning. https://yyahn.com 🚲🚲🚲

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01.06.2023
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Latest posts by YY Ahn @yyahn

Three scientists said no to you-know-who and were featured in the news (you may, somehow, be able to picture them). Nice. Good judgement.

But it's hard not to be cynical about this whole situation. (I'm resisting... resisting...)

06.03.2026 02:40 πŸ‘ 2 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0
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Data Visualization A Practical Introduction

Here’s a full draft of the upcoming second edition of my β€œData Visualization: A Practical Introduction”: socviz.co

05.03.2026 22:54 πŸ‘ 499 πŸ” 161 πŸ’¬ 12 πŸ“Œ 15
My first science video in 3 years
My first science video in 3 years YouTube video by Physics Girl

This video makes me so happy! She’s back!

youtube.com/watch?v=B3m3...

04.03.2026 01:30 πŸ‘ 5 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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Accessible PDF from LaTeX How to make LaTeX Curriculum vitae|CVs produce tagged, screen-reader-friendly PDFs -- relevant for ADA Title II compliance (deadline April 2026).

If you're unsure how to make your LaTeX-compiled PDFs (e.g., CV) accessible (compliant to the ADA requirements), this post may be useful.

yyahn.com/wiki/Accessi...

tl;dr: add metadata and use LuaLaTeX

26.02.2026 18:46 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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NYU is hiring two postdocs at the Center for Social Media, AI & Politics:
csmapnyu.org/jobs

And a grant manager in Sociology with the Social Science Research Hub:
uscareers-nyu.icims.com/jobs/15327/g...

I'm part of both groups--please share with anyone who is interested!

26.02.2026 03:13 πŸ‘ 37 πŸ” 41 πŸ’¬ 1 πŸ“Œ 0
The snake that eats its own tail More automation, more babysitting

I created a tool, snaketail, a snakemake wrapper that fixes workflow and restarts itself automatically when failed.

The ideaβ€”feeding the tail (error log) to the head (system input) to self-healβ€”has practical values to create robust automation system!

skojaku.github.io/snaketail.html

25.02.2026 10:37 πŸ‘ 5 πŸ” 2 πŸ’¬ 3 πŸ“Œ 0

Ah.. no worries! Yes, that's frustrating part that to fix anything, you need to fix other things, and then to fix any of those other things, you need to fix yet other things, ...

But I do feel that having fire dept have some smaller fire engines and allow narrow streets can be an important step

24.02.2026 21:13 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
How American Fire Departments are Getting People Killed
How American Fire Departments are Getting People Killed YouTube video by Not Just Bikes

I think the video I linked was useful for me on that front... I think it's primarily a historical legacy of big fire engines becoming the standard while the highway engineering standards become the way cities design their streets too? www.youtube.com/watch?v=j2dH...

24.02.2026 20:38 πŸ‘ 0 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

yeah a great headline πŸ˜‚

24.02.2026 13:36 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

It will be 3/4 6pm at CitySpace (100 5th St NE)!

www.charlottesville.gov/m/newsflash/...

24.02.2026 13:35 πŸ‘ 1 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0

πŸ‘€

www.404media.co/openai-furio...

futurism.com/future-socie...

24.02.2026 13:28 πŸ‘ 8 πŸ” 1 πŸ’¬ 1 πŸ“Œ 2
Event

Excited to join the panel "Innovation, Production, and Supply Chains in Critical Technologies" at CMU moderated by @andygarin.bsky.social and Erica Fuchs this Wednesday, 2/26 at 2pm! If you're in Pittsburgh, come say hi!

www.cs.cmu.edu/calendar/197...

24.02.2026 13:05 πŸ‘ 5 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0

I'll look forward to the discussions sparked by this!

24.02.2026 11:22 πŸ‘ 5 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0
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First blogpost of my cofounder post-Delhi on the deafening silence of public/political sphere as we come closer to another industrial revolution. anastasiastasenko.substack.com/p/the-countr...

23.02.2026 19:08 πŸ‘ 73 πŸ” 18 πŸ’¬ 3 πŸ“Œ 8
Using detailed address-level microdata, we trace movement chains originating with
the initial residents of The Central and document three main findings. First, we show
the building generated a substantial number of local vacancies. We identify 180 specific
addresses that became vacant because of moves into The Central. Scaling to account
for data coverage suggests the new tower induced more than 500 local vacancies in
the three years after construction, by setting off chains of moves. Second, while The
Central units were expensive on a per-square-foot basis, the homes vacated by movers
were significantly cheaper. Homes left behind by those moving into The Central were
about 40% less expensive. Unlike much of the prior literature, which track the changing
neighborhood characteristics of movers

Using detailed address-level microdata, we trace movement chains originating with the initial residents of The Central and document three main findings. First, we show the building generated a substantial number of local vacancies. We identify 180 specific addresses that became vacant because of moves into The Central. Scaling to account for data coverage suggests the new tower induced more than 500 local vacancies in the three years after construction, by setting off chains of moves. Second, while The Central units were expensive on a per-square-foot basis, the homes vacated by movers were significantly cheaper. Homes left behind by those moving into The Central were about 40% less expensive. Unlike much of the prior literature, which track the changing neighborhood characteristics of movers

Even more evidence that building new housing decreases rents: Researchers tracked the residents of a newly built luxury condo building and found that they freed up less expensive apartments nearby.
papers.ssrn.com/sol3/papers....

23.02.2026 15:00 πŸ‘ 1187 πŸ” 223 πŸ’¬ 29 πŸ“Œ 33
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Together with @mrjimmyblack.com (and Claude) we developed a tool that helps detecting hallucinated references in academic papers! This evolved from a simple python script into a full system written in Rust to quickly go through thousands of citations. Check it out!

github.com/gianlucasb/h...

23.02.2026 13:36 πŸ‘ 14 πŸ” 8 πŸ’¬ 0 πŸ“Œ 0

the deadline to submit to the WiNS satellite & mentorship program at @netsciconf.bsky.social is this friday!!

23.02.2026 11:40 πŸ‘ 3 πŸ” 6 πŸ’¬ 0 πŸ“Œ 0
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Cost of car ownership One day, a PhD student mentioned the unexpected high cost of car repairβ€”often over a thousand dollars, regardless of how cheap your car is. This got me...

Replacing a car with an e-bike can _literally_ make you a millionaire.

I wrote about a back-of-the-envelope math: a household can save ~$100k in just 5 years by going car-light. If this difference is invested over several decades, that can become $1M+

yyahn.com/wiki/Cost%20...

20.02.2026 16:04 πŸ‘ 9 πŸ” 4 πŸ’¬ 1 πŸ“Œ 0

We've alllllmost gotten all the Jan26 ARR reviews in, but I'm still trying to track down new emergency reviewers for papers on the following topics:
1) agents
2) jailbreaking
3) coding
4) RL
5) reasoning
6) LLM for finance
7) AMR
8) alignment
If you can review any (in next 24-48h) please DM me πŸ™πŸ™πŸ™

20.02.2026 04:39 πŸ‘ 3 πŸ” 9 πŸ’¬ 0 πŸ“Œ 0

A very good visual explanation of colon cancer risk.

20.02.2026 13:29 πŸ‘ 5 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0
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Happy to share our new paper published in PNAS!

Using epigenetic clocks and egocentric network data, we find each additional "hassler" in your close social network is associated with ~9 months of extra biological age and 1.5% faster pace of aging.

19.02.2026 13:07 πŸ‘ 20 πŸ” 9 πŸ’¬ 1 πŸ“Œ 1

A common but tedious task is to file a paper into my personal knowledge base (wiki/obsidian vault/whatever). just realized that this is a perfect task for subagent + skill. It can (1) use OpenAlex etc to obtain its metadata, (2) search and link keywords and other related papers. Seems to work well!

18.02.2026 02:09 πŸ‘ 6 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Revision now posted on the ArXiv! We collated and cleaned EVEN MORE DATA. 39M accounts, 365K starter packs, and 2.4B following relationships. All accounts, follows, and starter packs now have timestamps! Check it out at arxiv.org/abs/2505.11608.

15.02.2026 17:14 πŸ‘ 23 πŸ” 10 πŸ’¬ 1 πŸ“Œ 0
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Dozens of researchers will move to France from US following high-profile bid to lure talent Large proportion worked at Columbia University, which had its grants cut and frozen by the administration of US President Donald Trump.

Dozens of researchers will move to France from US following high-profile bid to lure talent. Large proportion worked at Columbia University, which had its grants cut and frozen by the administration of US President Donald Trump. www.nature.com/articles/d41...

10.02.2026 17:27 πŸ‘ 456 πŸ” 223 πŸ’¬ 18 πŸ“Œ 37
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Call for Proposals | Applied Machine Learning Conference A two-day conference bringing together data scientists, AI engineers, and ML practitioners in Charlottesville, VA. April 17-18, 2026.

Friendly reminder: the 2026 Applied Machine Learning Conference is still accepting abstracts for talks and workshops. Visit the call for proposals page for details! I hope to see you here in Charlottesville this April!

11.02.2026 21:45 πŸ‘ 3 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0
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Exclusive | OpenAI Executive Who Opposed β€˜Adult Mode’ Fired for Sexual Discrimination Ryan Beiermeister, who served as the vice president leading OpenAI’s product policy team, had raised concerns about the upcoming launch of erotic content.

OpenAI fired a female employee for sexual discrimination because she raised questions about the company's pivot toward automated erotica engagement slop

11.02.2026 14:50 πŸ‘ 327 πŸ” 124 πŸ’¬ 11 πŸ“Œ 11
Localities

C'ville folks! Local luminary and lender of e-bikes Josh Carp created this very cool site, which combines videos of public meetings with searchable, linkable transcripts. meetings.cvilledata.org/meetings

11.02.2026 02:47 πŸ‘ 17 πŸ” 9 πŸ’¬ 1 πŸ“Œ 1
Networks in Science of Science A NetSci 2026 Satellite Workshop

Excited for the Networks of Science of Science satellite at NetSCI 2026 this year in Boston!

netscisci.github.io

Be sure to submit by March 4th!

10.02.2026 14:22 πŸ‘ 6 πŸ” 4 πŸ’¬ 0 πŸ“Œ 0
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Livable Cville Presents Life After Cars with special guest Jamelle Bouie Doug Gordon and Sarah Goodyear will talk about their excellent new book β€œLife After Cars.

events.humanitix.com/livable-cvil...

Wow you can't miss this conversation @thewaroncars.bsky.social + @jamellebouie.net for Charlottesville! πŸ˜†

Thanks you @livablecville.bsky.social! This is awesome!

09.02.2026 02:02 πŸ‘ 19 πŸ” 7 πŸ’¬ 2 πŸ“Œ 1
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Toddler hospitalized with respiratory failure was returned to ICE detention without prescribed medication, lawsuit says The 18-month-old was sent back to a South Texas facility after days in intensive care with severe respiratory distress, according to a federal lawsuit.

NEW: A baby held in immigration detention became so sick, she had to be rushed to a hospital in severe respiratory distress.

β€œShe was at the brink of dying,” a lawyer told me.

But the girl didn’t go home after her 10-day hospital stay; instead, ICE put her and her mother back in lock up at Dilley.

07.02.2026 20:25 πŸ‘ 2626 πŸ” 1850 πŸ’¬ 101 πŸ“Œ 223