arXiv Computation and Language

Birth, Death and Diff: Insertion-Based Sequence Generation with Corrections

arXiv AI
Jul 28

UNIFUSION: Adapting Autoregressive Language Models into Discrete Diffusion under a Unified Reverse-Rate Objective

arXiv:2607. 24507v1 Announce Type: cross Abstract: Existing methods mainly adapt pretrained autoregressive (AR) language models to masked diffusion, whereas we directly adapt them to uniform-noise diffusion, where every token remains editable during sampling.

By Xiaoyi Jiang, Jingyuan Li, Yixuan Jiang, Wei Liu, Yi Zhu, Zuoqiang Shi, Pipi Hu
arXiv Machine Learning
1d ago

Corrective Diffusion Language Models

The paper introduces Corrective Diffusion Language Models (CDLMs), which enhance masked diffusion language models by explicitly supervising visible corrupted tokens to enable confidence-guided refinement of incorrect tokens. Experiments show that this correction-oriented post‑training improves iterative refinement and parallel decoding across models ranging from 0.5B to 8B, outperforming standard masked‑diffusion fine‑tuning on benchmarks such as Code Revision, HumanEval(+), and MATH. The authors also provide a new Code Revision Benchmark and release code and data for reproducibility.

By Shuibai Zhang, Fred Zhangzhi Peng, Yiheng Zhang, Jin Pan, Grigorios G. Chrysos
arXiv Machine Learning
Aug 31

DARTS: Decoder-Aware Representation Tuning via Surgery for Model Merging

The paper introduces DARTS, a method for tuning decoder representations during model merging. It addresses representation bias in autoregressive decoders by using an entropy‑weighted L1 loss and a per‑position additive bias to correct errors that accumulate across token positions. Experiments on code generation, mathematical reasoning, and instruction following with Llama‑2‑7B show that DARTS improves performance over standard surgery while adding only 0.1% extra parameters.

By Aaryan Ajay Sharma, Sai Nishanth Padala, Seganrasan Subramanian
arXiv Machine Learning
Sep 4

Unlocking Lossless Speedups in LLMs via Discrete Diffusion

arXiv:2609. 04010v1 Announce Type: new Abstract: Large Language Models (LLMs) owe much of their success to next-token prediction (NTP), but their autoregressive (AR) structure requires slow, sequential token generation.

By Subham Sekhar Sahoo, Lingjie Chen, Khiem Pham, Jonathan Geuter, Chaitanya Dwivedi, Varad Pimpalkhute, Yash Akhauri, Alexander Moreno, Mikhail Yurochkin, Zhenting Wang, Mostafa Elhoushi, Nolan Dey, Shane Bergsma, Joel Hestness, John Thickstun, Eric Xing, Zhengzhong Liu
arXiv Computation and Language
5d ago

The Generative Gap Between Speculative Drafter and Continuous Diffusion Language Model

The study compares continuous diffusion language models (CDLMs) and speculative drafters by training them from scratch on unconditional OpenWebText generation at lengths 16, 128, and 1024. Using LangFlow for CDLMs and adapted DSpark Markov and recurrent-head architectures for standalone generation, the authors evaluate generation perplexity (GenPPL) and MAUVE similarity. Results show LangFlow outperforms both DSpark variants at longer lengths (128 and 1024), while DSpark-RNN leads at length 16; recurrent memory and teacher probability matching improve metrics but the longer‑sequence gap remains, highlighting iterative full‑sequence refinement as a key advantage.

By Yujian Chen, Hao Jiang, Guang Cheng, Weijian Luo, Tianyang Hu
arXiv Computation and Language
Aug 27

SimLens for Early Exit in Large Language Models: Eliciting Accurate Latent Predictions with One More Token

SimLens is a training‑free decoder that improves early‑layer predictions in large language models by keeping only the start token and a candidate answer token and performing a lightweight continuation through the remaining layers. It outperforms direct linear readouts, yielding higher accuracy on tasks such as ARC, BoolQ, and HeadQA with LLaMA‑7B and Vicuna‑7B. The method is extended to Linear SimLens for confidence estimation and combined into SimExit, a hybrid early‑exit mechanism that achieves significant speedups while maintaining accuracy.

By Ming Ma, Bowen Zheng, Zhongqiao Lin, Tianming Yang
arXiv Machine Learning
Oct 19

LED: Improving Masked Diffusion Language Models by Lookahead Editing

The paper introduces Lookahead Editing (LED), a method that enhances masked diffusion language models (MDMs) by adding a rewritable proposal state. LED performs multiple lookahead updates at each decoding step to refine future predictions before committing tokens, thereby improving expressivity while retaining MDMs’ simple transition schedule. Fine‑tuned LED models (LED‑7B and LED‑8B) achieve significant performance gains on eight benchmarks and outperform larger models such as LLaDA2.1‑16B using only supervised fine‑tuning.

By Yuyan Zhou, Zeyuan Yang, Yuxuan Song, Zhicheng Cai, Hongli Yu, Weiying Ma, Hao Zhou, James Kwok