arXiv Computer Vision

Not Every Subject Should Stay: Machine Unlearning for Noisy Engagement Recognition

The paper investigates subject-level machine unlearning as a post‑hoc sanitization technique for engagement recognition datasets that are subject‑indexed and often noisy. By ranking harmful subjects with a model‑dependent proxy and applying a lightweight approximate unlearning update, the authors compare the resulting model to an oracle retrained from scratch on the remaining subjects. Experiments on DAiSEE and EngageNet show that the unlearned model recovers roughly 90–93% of the oracle’s performance at about one‑quarter the retraining cost, with effectiveness peaking at intermediate forget‑set sizes.

arXiv AI
Sep 1

Forget or Fine-tune? A Comparative Study of Machine Unlearning Strategies for Noisy Label Correction

The paper compares five machine unlearning (MU) methods—NegGrad, Fine‑Tuning (FT), Random Labeling (RL), SalUn, and MUNBa—on noisy‑label correction across CIFAR‑10, CIFAR‑100, and Food‑101N. Results show that the best MU strategy depends on the noise type: FT works well for most closed‑set noise, RL and SalUn are robust and nearly match retraining accuracy under instance‑dependent noise, while MUNBa excels only under extreme symmetric noise. In open‑set noise, retraining on the cleaned data actually hurts performance, indicating that approximating retraining is not suitable in that regime, yet all MU methods still achieve near‑retraining accuracy on Food‑101N with much lower runtime.

By Jo\~ao L. P. Santana, Filipe R. Cordeiro
arXiv Machine Learning
Oct 9

Class Machine Unlearning for Complex Data via Concepts Inference and Data Poisoning

The paper introduces a concept-guided poisoning unlearning framework that explicitly identifies semantic concepts most strongly linked to a target class or knowledge. For image classification, it uses a Post-hoc Concept Bottleneck Model to locate relevant image regions and creates poisoned samples; for large language models, it aggregates Integrated Gradients over multiple question responses to mask important content and generate poisoned training targets. Experiments across several datasets demonstrate effective unlearning while largely preserving model utility.

By Wenhan Chang, Tianqing Zhu, Heng Xu, Wenjian Liu, Wanlei Zhou
arXiv Computation and Language
Sep 24

RapidUn: Influence-Driven Parameter Reweighting for Efficient Large Language Model Unlearning

RapidUn is a parameter reweighting framework that uses influence estimates to guide LoRA-only updates for efficient unlearning of targeted behaviors in large language models. It operates in a practical PEFT setting with a small forget set and limited retain buffer, converting cross-sample influence into fixed sample-specific weights for weighted LoRA unlearning. Experiments on Llama‑3‑8B with Dolly‑15k and Alpaca‑57k datasets show RapidUn achieves lower trigger ASR than Fisher, GA, and LoReUn while preserving clean utility, and delivers a 77× wall‑clock speedup over clean‑corpus LoRA retraining, with additional evaluations supporting its effectiveness.

By Guoshenghui Zhao, Huawei Lin, Weijie Zhao
arXiv AI
Jun 3

PURGE: Projected Unlearning via Retain-Guided Erasure

arXiv:2606. 03808v1 Announce Type: cross Abstract: We propose PURGE, a machine unlearning algorithm built on a simple but an under-exploited observation: continual learning (CL) and machine unlearning (MU) which are fundamentally dual problems.

By Vedant Jawandhia, Daksh Ahuja, Ghufran Alam Siddiqui, Prashant Trivedi, Yash Sinha, Pratik Narang
arXiv AI
Oct 1

Unmerge: Efficient Machine Unlearning via Task Arithmetic

The paper introduces Unmerge, an efficient machine unlearning algorithm that treats unlearning as the inverse of task arithmetic. By representing the forget component as a low‑rank basis at each layer, Unmerge optimizes three goals—matching the merged vector, suppressing leakage, and bounding correction size—to limit forget leakage and retain damage. Experiments on ResNet‑50, ViT‑S/16, and Llama‑3.2‑3B show significant performance gains over existing methods while maintaining privacy and feature‑distribution fidelity.

By Haoran Tang, Andrew Tan, Rajiv Khanna
arXiv AI
Sep 11

Forgetting Only What Matters: Layer-Selective Unlearning toward Robust LLMs

The paper introduces Forgetting Only What Matters via Unlearning Layers (FOM-UL), a layer‑selective unlearning framework for large language models. FOM-UL uses a forget‑to‑retain significance score to identify transformer layers that strongly influence the forget set while being insensitive to the retain set, allowing targeted updates that preserve most of the model. Experiments on TOFU, KnowUnDo, and MUSE-style benchmarks show that FOM-UL reduces residual memorization and maintains utility better than several baselines, even after 8‑bit and 4‑bit post‑training quantization, and it also limits recovery of forgotten content in adversarial prompt tests.

By Ravi Ranjan, Olivera Kotevska, Agoritsa Polyzou