🚨 New paper alert: A new generation of LLMs can now process speech natively. This could expand access for millions excluded by text interfaces, but our research shows a cost: demographic cues in speaker voice can trigger stereotypical model responses. 🎙️⚖️ Paper: arxiv.org/abs/2603.22260
Valentin Hofmann
@valentinhofmann.bsky.social
Assistant Professor @cislmu.bsky.social @lmu.de
📢 Life update 📢 After a wonderful time at @ai2.bsky.social, I've joined @cislmu.bsky.social at @lmu.de as a tenure-track assistant professor in NLP. Thrilled to be back in Europe and to start a lab in Munich's flourishing AI ecosystem! 🎉
Demographic cues (eg, names, dialect) are widely used to study how LLM behavior may change depending on user demographics. Such cues are often assumed interchangeable. 🚨 We show they are not: different cues yield different model behavior for the same group and different conclusions on LLM bias. 🧵👇
Introducing Bolmo, a new family of byte-level language models built by "byteifying" our open Olmo 3—and to our knowledge, the first fully open byte-level LM to match or surpass SOTA subword models across a wide range of tasks. 🧵
Excited to see our #COLM2025 paper on fluid benchmarking highlighted by @eval-eval.bsky.social! They are worth a follow if you are into LLM eval research. 🔬
✨ Weekly AI Evaluation Paper Spotlight ✨ 🤔Is it time to move beyond static tests and toward more dynamic, adaptive, and model-aware evaluation? 🖇️ "Fluid Language Model Benchmarking" by @valentinhofmann.bsky.social et. al introduces a dynamic benchmarking method for evaluating language models
There’s plenty of evidence for political bias in LLMs, but very few evals reflect realistic LLM use cases — which is where bias actually matters. IssueBench, our attempt to fix this, is accepted at TACL, and I will be at #EMNLP2025 next week to talk about it! New results 🧵
Are LLMs biased when they write about political issues? We just released IssueBench – the largest, most realistic benchmark of its kind – to answer this question more robustly than ever before. Long 🧵with spicy results 👇
Check out this #EMNLP2025 paper led by @minhducbui.bsky.social and @carolin-holtermann.bsky.social showing dialect prejudice remains a major issue in current LLMs. Example: GPT-5 associates German dialect speakers with being uneducated and steers them toward stereotyped jobs (e.g., farmworkers). 👇
“You speak Bavarian? Then you must be uneducated + closed-minded.” 🤯 Not your opinion? Good. But it might be your LLM’s!! 🧵 Check out our #EMNLP2025 paper, where we uncover concerning dialect bias in recent LLMs - including GPT-5. #AI #Bias #Dialect #Fairness #LLM #NLProc #Safety
LM benchmark design requires 3 decisions, how to: 🐟 select test cases 🐠 score LM on each test 🦈 aggregate scores to estimate perf fluid benchmarking is simple: 🍣 find max informative test cases 🍥 estimate 'ability', not simple avg perf why care? turn ur grey noisy benchmarks to red ones!
📢 New #COLM2025 paper 📢 Standard benchmarks give every LLM the same questions. This is like testing 5th graders and college seniors with *one* exam! 🥴 Meet Fluid Benchmarking, a capability-adaptive eval method delivering lower variance, higher validity, and reduced cost. 🧵
📢 New #COLM2025 paper 📢 Standard benchmarks give every LLM the same questions. This is like testing 5th graders and college seniors with *one* exam! 🥴 Meet Fluid Benchmarking, a capability-adaptive eval method delivering lower variance, higher validity, and reduced cost. 🧵
🚀 Introducing Fluid Benchmarking—an adaptive way to evaluate LLMs. Inspired by psychometrics, it tailors which questions to ask based on each model’s capability, making evals more efficient & reliable. 🧵
I am delighted to share our new #PNAS paper, with @grvkamath.bsky.social @msonderegger.bsky.social and @sivareddyg.bsky.social, on whether age matters for the adoption of new meanings. That is, as words change meaning, does the rate of adoption vary across generations? www.pnas.org/doi/epdf/10....
Attending #ICML2025? Don't miss this TokShop panel, which will explore: 🔮 The Future of Tokenization 🔮 Featuring a stellar lineup of panelists - mark your calendar! ✨
🎤 Meet our expert panelists! Join Albert Gu, Alisa Liu, Kris Cao, Sander Land, and Yuval Pinter as they discuss the Future of Tokenization on July 18 at 3:30 PM at TokShop at #ICML2025.
LLMs can appear unbiased on the surface but still perpetuate racist views in subtle ways. What causes this discrepancy? 🔍 In our upcoming #ACL2025 paper, we find a pattern akin to racial colorblindness: LLMs suppress race in ambiguous contexts, leading to biased outcomes.
🚨New #ACL2025 paper! Today’s “safe” language models can look unbiased—but alignment can actually make them more biased implicitly by reducing their sensitivity to race-related associations. 🧵Find out more below!
📣 We extend the submission deadline by 24 hours to avoid conflict with ACL camera-ready deadline. 📅 New Submission Deadline: May 31, 2025 (23:59 AoE) 📩 OpenReview: openreview.net/group?id=ICM...
ICML 2025 Workshop TokShop
Welcome to the OpenReview homepage for ICML 2025 Workshop TokShop
openreview.net
📣 Call for Paper Alert: TokShop @ ICML 2025 TokShop explores tokenization across all data modalities. Topics include: subword NLP techniques, multimodal approaches, multilingual challenges, post-training modification, alternative representations, and statistical perspectives.
Got a good tokenization paper under review at COLM, but the scores were a letdown? 😬 Why bother with rebuttal when the perfect venue is right around the corner! Submit your paper to the #ICML2025 Tokenization Workshop (TokShop) by May 30! 🚀
Beyond text: Modern AI tokenizes images too! Vision models split photos into patches, treating each 16x16 pixel square as a "token." 🖼️➡️🔤 #VisualTokenization Interested in tokenization? Join our workshop tokenization-workshop.github.io The submission deadline is already May 30!
tokenization-workshop.github.io
Do LLMs learn language via rules or analogies? This could be a surprise to many – models rely heavily on stored examples and draw analogies when dealing with unfamiliar words, much as humans do. Check out this new study led by @valentinhofmann.bsky.social to learn how they made the discovery 💡
Thrilled to share that this is out in @pnas.org today! 🎉 We show that linguistic generalization in language models can be due to underlying analogical mechanisms. Shoutout to my amazing co-authors @weissweiler.bsky.social, @davidrmortensen.bsky.social, Hinrich Schütze, and Janet Pierrehumbert!
Thrilled to share that this is out in @pnas.org today! 🎉 We show that linguistic generalization in language models can be due to underlying analogical mechanisms. Shoutout to my amazing co-authors @weissweiler.bsky.social, @davidrmortensen.bsky.social, Hinrich Schütze, and Janet Pierrehumbert!
📢 New paper 📢 What generalization mechanisms shape the language skills of LLMs? Prior work has claimed that LLMs learn language via rules. We revisit the question and find that superficially rule-like behavior of LLMs can be traced to underlying analogical processes. 🧵
Got a tokenization paper that just didn't make the cut for ICML? Submit it to the Tokenization Workshop TokShop at #ICML2025 -- we'd love to see it there! tokenization-workshop.github.io
Tokenization Workshop @ ICML 2025
tokenization-workshop.github.io
Next was a fantastic talk by @valentinhofmann.bsky.social on probing covert racism in LLMs at the @ltiatcmu.bsky.social. One can imagine where this goes. Highly recommend www.youtube.com/watch?v=_1Ej... (5/11)
4.18.25 LTI Colloquium Valentin Hofmann
YouTube video by Language Technologies Institute at Carnegie Mellon (LTI at CMU)
youtube.com
Delighted there will finally be a workshop devoted to tokenization - a critical topic for LLMs and beyond! 🎉 Join us for the inaugural edition of TokShop at #ICML2025 @icmlconf.bsky.social in Vancouver this summer! 🤗
🚨 NEW WORKSHOP ALERT 🚨 We're thrilled to announce the first-ever Tokenization Workshop (TokShop) at #ICML2025 @icmlconf.bsky.social! 🎉 Submissions are open for work on tokenization across all areas of machine learning. 📅 Submission deadline: May 30, 2025 🔗 tokenization-workshop.github.io
We created Approximate Likelihood Matching, a principled (and very effective) method for *cross-tokenizer distillation*! With ALM, you can create ensembles of models from different families, convert existing subword-level models to byte-level and a bunch more🧵
Humans store thousands of multi-word expressions like "of course" in their mental lexicon, but current tokenizers don't support multi-word tokens. Enter SuperBPE, a tokenizer that lifts this restriction and brings substantial gains in efficiency and performance! 🚀 Details 👇
We created SuperBPE🚀, a *superword* tokenizer that includes tokens spanning multiple words. When pretraining at 8B scale, SuperBPE models consistently outperform the BPE baseline on 30 downstream tasks (+8% MMLU), while also being 27% more efficient at inference time.🧵
New preprint! Metaphors shape how people understand politics, but measuring them (& their real-world effects) is hard. We develop a new method to measure metaphor & use it to study dehumanizing metaphor in 400K immigration tweets Link: bit.ly/4i3PGm3 #NLP #NLProc #polisky #polcom #compsocialsci 🐦🐦
✨New paper✨ Linguistic evaluations of LLMs often implicitly assume that language is generated by symbolic rules. In a new position paper, @adelegoldberg.bsky.social, @kmahowald.bsky.social and I argue that languages are not Lego sets, and evaluations should reflect this! arxiv.org/pdf/2502.13195
Excited to share IssueBench, the most extensive benchmark for LLM political bias! 📊 We find surprising consistency across models, with notable differences in Qwen on China-related issues. All examined LLMs also show strong alignment with Democrat voters. More details below! 👇
Are LLMs biased when they write about political issues? We just released IssueBench – the largest, most realistic benchmark of its kind – to answer this question more robustly than ever before. Long 🧵with spicy results 👇
Great to see the International AI Safety Report highlight research on dialect prejudice, including our work on covert racism in LLMs! www.nature.com/articles/s41...
Today, we are publishing the first-ever International AI Safety Report, backed by 30 countries and the OECD, UN, and EU. It summarises the state of the science on AI capabilities and risks, and how to mitigate those risks. 🧵 Full Report: assets.publishing.service.gov.uk/media/679a0c... 1/21
Today, we are releasing MSTS, a new Multimodal Safety Test Suite for vision-language models! MSTS is exciting because it tests for safety risks *created by multimodality*. Each prompt consists of a text + image that *only in combination* reveal their full unsafe meaning. 🧵
📢 New paper 📢 What generalization mechanisms shape the language skills of LLMs? Prior work has claimed that LLMs learn language via rules. We revisit the question and find that superficially rule-like behavior of LLMs can be traced to underlying analogical processes. 🧵