karen_ullrich Profile Banner
Dr. Karen Ullrich Profile
Dr. Karen Ullrich

@karen_ullrich

Followers
5K
Following
584
Media
37
Statuses
272

Research scientist at FAIR NY + collab w/ Vector Institute. ❤️ Machine Learning + Information Theory. Previously, PhD at UoAmsterdam, intern at DeepMind + MSRC.

she / her
Joined December 2013
Don't wanna be here? Send us removal request.
@karen_ullrich
Dr. Karen Ullrich
10 months
#Tokenization is undeniably a key player in the success story of #LLMs but we poorly understand why. I want to highlight progress we made in understanding the role of tokenization, developing the core incidents and mitigating its problems. 🧵👇.
15
95
608
@karen_ullrich
Dr. Karen Ullrich
2 months
Plus, we generate importance maps showing where in the transformer the concept is encoded — providing interpretable insights into model internals.
Tweet media one
1
0
4
@karen_ullrich
Dr. Karen Ullrich
2 months
SAMI: Diminishes or amplifies these modules to control the concept's influence. With SAMI, we can scale the importance of these modules — either amplifying or suppressing specific concepts.
Tweet media one
1
0
2
@karen_ullrich
Dr. Karen Ullrich
2 months
SAMD: Finds the attention heads most correlated with a concept. Using SAMD, we find that only a few attention heads are crucial for a wide range of concepts—confirming the sparse, modular nature of knowledge in transformers.
Tweet media one
1
0
2
@karen_ullrich
Dr. Karen Ullrich
2 months
How would you make an LLM "forget" the concept of dog — or any other arbitrary concept? 🐶❓. We introduce SAMD & SAMI — a novel, concept-agnostic approach to identify and manipulate attention modules in transformers.
Tweet media one
Tweet media two
3
12
78
@karen_ullrich
Dr. Karen Ullrich
4 months
0
0
3
@karen_ullrich
Dr. Karen Ullrich
4 months
Aligned Multi-Objective Optimization (A-🐮) has been accepted at #ICML2025! 🎉 .We explore optimization scenarios where objectives align rather than conflict, introducing new scalable algorithms with theoretical guarantees. #MachineLearning #AIResearch #Optimization #MLCommunity
Tweet media one
3
12
88
@karen_ullrich
Dr. Karen Ullrich
8 months
0
0
4
@karen_ullrich
Dr. Karen Ullrich
8 months
🎉Our paper just got accepted to #ICLR2025! 🎉. Byte-level LLMs without training and guaranteed performance? Curious how? Dive into our work! 📚✨ . Paper: Github:
Tweet media one
2
14
111
@karen_ullrich
Dr. Karen Ullrich
9 months
RT @brandondamos: 📢 My team at Meta is hiring visiting PhD students from CMU, UW, Berkeley, and NYU! We study core ML, optimization, amorti….
0
42
0
@karen_ullrich
Dr. Karen Ullrich
9 months
RT @hall__melissa: Excited to release EvalGIM, an easy-to-use evaluation library for generative image models. EvalGIM ("EvalGym") unifies….
Tweet card summary image
github.com
🦾 EvalGIM (pronounced as "EvalGym") is an evaluation library for generative image models. It enables easy-to-use, reproducible automatic evaluations of text-to-image models and su...
0
15
0
@karen_ullrich
Dr. Karen Ullrich
9 months
Thursday is busy:.9-11am I will be at the Meta AI Booth.12.30-2pm.Mission Impossible: A Statistical Perspective on Jailbreaking LLMs (.OR.End-To-End Causal Effect Estimation from Unstructured Natural Language Data (.
0
0
8
@karen_ullrich
Dr. Karen Ullrich
9 months
RT @KempeLab: For those into jailbreaking LLMs: our poster "Mission Impossible" today shows the fundamental limits of LLM alignment - and i….
0
4
0
@karen_ullrich
Dr. Karen Ullrich
9 months
Starting with Fei-Fei Li’s talk 2.30, after that I will mostly be meeting people and wonder the poster sessions.
0
0
3
@karen_ullrich
Dr. Karen Ullrich
9 months
Folks, I am posting my NeurIPS schedule daily in hopes to see folks, thanks @tkipf the idea ;). 11-12.30 WiML round tables.1.30-4 Beyond Decoding, Tutorial.
0
0
10
@karen_ullrich
Dr. Karen Ullrich
10 months
RT @NYUDataScience: Researchers at CDS and @AIatMeta prove vulnerabilities in AI language models are unavoidable, but introduce E-RLHF, a m….
Tweet card summary image
nyudatascience.medium.com
CDS and Meta AI researchers have shown that language model vulnerabilities are inevitable but have developed a new method to make them…
0
9
0
@karen_ullrich
Dr. Karen Ullrich
10 months
What do you think do we need to sharpen our understanding of tokenization? Or will we soon be rid of it by developing models such as "MegaByte" by @liliyu_lili et al (@lukezettlemoyer)? . And add more paper to the threat!
Tweet media one
3
2
29
@karen_ullrich
Dr. Karen Ullrich
10 months
@buutphan et al, found a method to mitigate some of the tokenization problems @karpathy mentioned by projecting tokens into byte space. The key to their method is to develop a map between statistically equivalent token and byte-level models.
Tweet media one
1
2
28
@karen_ullrich
Dr. Karen Ullrich
10 months
In "The Foundations of Tokenization:.Statistical and Computational Concerns", Gastaldi et al. try to make first steps towards defining what a tokenizer should be and define properties it ought to have.
Tweet media one
1
1
26