arXiv Machine Learning

Mitigating Memorization Where It Happens

The paper introduces a token‑level log‑likelihood ratio to pinpoint where large language models memorize training sequences. It proposes a probe‑steer framework, instantiated as Gated Subspace Steering (GSS), that selectively corrects memorization‑relevant activations using the leading singular vectors of a gradient‑weighted activation matrix. Experiments on four benchmarks show GSS matches or surpasses state‑of‑the‑art memorization reduction methods while using 10–100× less compute.

arXiv AI
Oct 1

Mitigating Memorization In Language Models

The paper explores ways to reduce the memorization of training data in language models, testing three regularizer-based, three finetuning-based, and eleven machine unlearning methods—five of which are newly introduced. It introduces TinyMem, a lightweight suite of small models for rapid testing of these mitigation techniques, and shows that unlearning methods, particularly BalancedSubnet, outperform others in removing memorized content while maintaining task performance. The study also finds that regularizer-based approaches are slow and ineffective, while finetuning methods are costly, especially when high accuracy is required.

By Mansi Sakarvadia, Aswathy Ajith, Arham Khan, Nathaniel Hudson, Caleb Geniesse, Kyle Chard, Yaoqing Yang, Ian Foster, Michael W. Mahoney
arXiv Machine Learning
Jul 15

Inference-Time Machine Unlearning via Gated Activation Redirection

arXiv:2605. 12765v3 Announce Type: replace Abstract: Large Language Models memorize vast amounts of training data, raising concerns regarding privacy, copyright infringement, and safety.

By Vin\'icius Conte Turani, Ot\'avio Parraga, Jo\~ao Vitor Boer Abitante, Kristen K. Arguello, Joana Pasquali, Ramiro N. Barros, Flavio du Pin Calmon, Christian Mattjie, Rodrigo C. Barros, Lucas S. Kupssinsk\"u
arXiv Computation and Language
3d ago

Output Vector Editing for Memorization Mitigation in Large Language Models

Output Vector Editing (OVE) is a post‑hoc technique that suppresses unwanted text continuations from large language models by editing the output vectors of specific neurons. It uses a two‑stage localization of MLP layers and neurons combined with full‑vocabulary least‑squares updates, and its multi‑anchor variant (OVE‑MA) adaptively selects continuation positions to maximize suppression. Experiments on models ranging from 360 M to 7 B parameters show that OVE‑MA can reduce recoverable continuations by 24.45 % with only five output‑vector updates, outperforming the prior method REVS while requiring far fewer updates.

By Ahmad Dawar Hakimi, Kaiwei Lei, Isabelle Augenstein, Hinrich Sch\"utze
arXiv AI
Aug 25

Unlearning Is Not Just Erasing: Temporal Decoupling via Generation Inequality

The paper introduces ADU, a fine‑grained training framework that unlearns sensitive information from large language models by decoupling contextual attention pathways instead of erasing tokens. ADU exploits the distinction between local and global attention heads to identify and suppress attention paths that retrieve persistent sensitive anchors, while preserving local‑attention structure and overall language modeling performance. Evaluation on the TOFU and WMDP benchmarks shows ADU achieves superior forget quality (0.93 on TOFU) and retains 92.9% of model utility compared to 81.9% for existing baselines, with fewer side effects in benign contexts.

By Xunlei Chen, Qirui Ye, Yuang Li, Yi Gong, Zhaokun Wang, Wenyi Li, Shiyao Guo, Jinyu Guo
arXiv Machine Learning
Oct 5

Fisher-Guided Submodular Data Selection for Continual Pre-Training of Large Language Models

The paper introduces a Fisher-guided submodular data selection method for continual pre‑training of large language models, addressing the forgetting problem that arises when a target‑domain corpus overwrites pretrained knowledge. By decomposing candidate gradients into anchor and frontier components and optimizing a log‑determinant submodular objective, the method selects data that both improves target‑domain performance and limits forgetting. Experiments on TinyLlama‑1.1B and Llama‑3.1‑8B show that the selector achieves superior adaptation and forgetting control while using ten times fewer tokens than traditional replay strategies.

By Zhenghao Zhao, Gaowen Liu, Zhiling Lan, Yan Yan
arXiv AI
Oct 16

Towards Continual Learning: Mitigating Forgetting With Subspace Tuning

The paper introduces Subspace Tuning (SST), a fine‑tuning technique that restricts weight updates to the bottom singular subspace of model parameters, thereby protecting the principal directions that are most prone to catastrophic forgetting. SST is optimizer‑agnostic, works with existing fine‑tuning recipes such as SFT and self‑distillation, and includes dense gradient estimation and a refresh mechanism to enhance learning. Experiments show that SST can preserve up to 99 % of the weight subspace, significantly reduce KL drift, and nearly eliminate forgetting in large‑scale language models while maintaining strong target‑task performance.

By Arnav Chavan, Kusha Sareen, Rishabh Tiwari, Abhranil Chandra, Johan Obando-Ceron, Kurt Keutzer, Scott Niekum, Inderjit S Dhillon, Devvrit Khatri
Hugging Face Trending Papers
Oct 15

Towards Continual Learning: Mitigating Forgetting With Subspace Tuning

The paper introduces Subspace Tuning (SST), a fine‑tuning technique that confines weight updates to the bottom singular subspace of model parameters, thereby avoiding changes along principal directions that cause catastrophic forgetting. SST is optimizer‑agnostic, works with existing fine‑tuning recipes, and includes dense gradient estimation and a refresh mechanism. Experiments show that protecting up to 99% of the weight subspace significantly reduces forgetting, improves retention, and maintains strong target‑task performance, especially in large‑model regimes, while also reducing KL drift by 2–4× compared to baseline methods.