arXiv Machine Learning

Towards a theory of inference-time alignment with unknown rewards

arXiv:2608. 15402v1 Announce Type: new Abstract: Generative model alignment has received broad interest, and significant progress has been made in supervised fine-tuning and inference-time computation.

arXiv AI
3d ago

Multi-LLM Collaborative Alignment via Stackelberg Games

The paper introduces Stackelberg Alignment, a leader‑follower framework that lets a pool of language models collaborate and improve by learning from each other’s responses. An EXP3 bandit leader adaptively selects instructions based on difficulty and discriminability, while the models act as followers, evaluating peers and learning via DPO or GRPO with Elo‑style reputation weighting and opponent matching. Experiments on diverse benchmarks show that this adaptive curriculum outperforms static baselines by up to 12‑25% and improves multi‑LLM evolution.

By Christina Hahn, Shangbin Feng, Dean Light, Swastik Roy, Hila Gonen, Yulia Tsvetkov
arXiv Machine Learning
Sep 4

ALRA: Adaptive Local Relational Alignment for Logit-Based Pre-training Distillation of Autoregressive Language Models

The paper introduces Adaptive Local Relational Alignment (ALRA), a logit‑based knowledge distillation method for autoregressive language models that combines student‑generated token proposals with teacher guidance at each prediction position. ALRA dynamically selects the number of candidate tokens based on the teacher’s probability spread, uses Adaptive Local Divergence to match both mass and relative token distributions, and applies Student‑Weighted Pairwise Relational Alignment to focus on high‑probability token pairs. Experiments on The Pile show that 200M‑ and 500M‑parameter students trained with ALRA outperform the best baseline by roughly 1 percentage point and surpass pre‑training without distillation by over 2 percentage points on nine zero‑shot benchmarks.

By Quang Hoang Trung, Quang Huu Hieu, Nguyen Van Hoang Phuc, Vo Nguyen Le Duy
arXiv Machine Learning
Sep 4

Gradients Know What Outcomes Don't: Unlocking Reinforcement Learning for LLM Reasoning with Gradient-Aligned Rewards

The paper introduces Gradient-Aligned Reward (GAR), a reinforcement learning technique that uses truncated backpropagation to generate a compact gradient vector for each rollout and compares it to an expert-anchor gradient via cosine similarity. This dense, reasoning-aware reward improves large language model chain-of-thought reasoning on math benchmarks and transfers to other tasks without domain‑specific data, while adding less than 9% computational overhead. GAR outperforms existing baselines such as GRPO on Qwen3-4B and Qwen3-8B models.

By Leqi Zheng, Jinbo Su, Fang Niu, Chaokun Wang, Weiping Wang, Jiajun Zhang, Shannan Yan, Jie Wu, Zhaolu Kang, Rong Fu, Hang Zhang