arXiv AI

Climate-ModernBERT: Revisiting Corpus Composition for Domain-Adaptive Continued Pretraining

arXiv Machine Learning
Jul 31

How Can We Synthesize High-Quality Pretraining Data? A Systematic Study of Prompt Design, Generator Model, and Source Data

arXiv:2604. 13977v2 Announce Type: replace-cross Abstract: Synthetic data is a standard component in training large language models, yet systematic comparisons across design dimensions, including rephrasing strategy, generator model, and source data, remain absent.

By Joel Niklaus, Atsuki Yamaguchi, Michal \v{S}tef\'anik, Guilherme Penedo, Hynek Kydl\'i\v{c}ek, Elie Bakouch, Lewis Tunstall, Edward Emanuel Beeching, Thibaud Frere, Colin Raffel, Leandro von Werra, Thomas Wolf
arXiv Machine Learning
Aug 27

Unfolding Scientific Papers into Multi-Turn Generation Trajectories for Continued Pre-Training

arXiv:2608. 25826v1 Announce Type: cross Abstract: A recent line of synthetic-data work reconstructs the thinking behind existing text rather than rewriting the text itself, but it operates on short web passages, recovers only local thoughts, and leaves the structure of whole documents untouched.

By Qiankai Xu, Qiguang Chen, Zixin Su, Wenhao Huang, Yue Gao, Jiaheng Liu, Ge Zhang
arXiv Computation and Language
Oct 15

AFCS: Atomic-Fact-Conditioned Synthesis for Factual Knowledge Pretraining

AFCS (Atomic‑Fact‑Conditioned Synthesis) is a new pipeline for generating synthetic data for language‑model pretraining that focuses on extracting and using fine‑grained atomic facts from source documents. Unlike previous methods such as WRAP and Nemotron‑CC, AFCS explicitly requires secondary entities, list/table entries, and precise temporal attributes to appear in the synthesized corpus, employing structure‑aware extraction, source‑grounded verification, local context expansion, and multi‑format generation. In experiments with OLMo‑3‑7B and a 32B model on the FineWiki corpus, AFCS outperforms the baselines on several QA benchmarks and improves general benchmark performance by +1.09 when integrated mid‑training with 100B tokens.

By Yunhao Wang, Feng Zhang, Tinghao Yu, Xing Wu, Jiang Zhou
arXiv Computation and Language
Aug 25

LuxIT: A Luxembourgish Instruction Tuning Dataset from Monolingual Seed Data

LuxIT is a monolingual instruction‑tuning dataset for Luxembourgish, created by synthesizing instruction‑answer pairs from native texts using the DeepSeek‑R1‑0528 model and a quality‑assurance LLM‑as‑judge process. The resulting 227,507 high‑quality pairs were used to fine‑tune 14 LLMs (≤15 B parameters), yielding an average accuracy increase of +5.37 percentage points on standardized Luxembourgish proficiency exams and improvements in macro‑averaged F1 on nine of the fourteen downstream NLP tasks. These findings demonstrate that synthetic monolingual data can effectively enhance LLM performance in low‑resource languages and reveal the complex relationship between exam performance and practical NLP gains.

By Julian Valline, Cedric Lothritz, Siwen Guo, Jordi Cabot
arXiv Computation and Language
6d ago

Dataset Collection and Fine-Tuning of NLLB for German--English Translation

The paper presents a curated German–English parallel corpus derived from OPUS Books, reduced from 45,000 raw sentence pairs to 25,000 high‑quality examples through filtering and quality scoring. It details a reproducible fine‑tuning process for Meta’s NLLB‑200 models using mixed precision and gradient techniques, yielding a fine‑tuned NLLB‑600M model that improves BLEU, chrF++, and TER scores on literary and technical translations. The authors also integrate the model into the LinguaHaru translation system, enabling format‑preserving translation of PDFs and Office documents, and release all scripts, code, and the model on HuggingFace.

By SK Deeraj, Yash Ingle, Pruthwik Mishra
arXiv Computation and Language
Oct 5

RT-SFT: Text Style Transfer from Non-Parallel Corpora by Roundtrip Translation

RT‑SFT is a method for text style transfer that uses roundtrip translation through a pivot language to strip stylistic information from monolingual corpora, creating pseudo‑parallel data. This data is then used to LoRA‑finetune an instruction‑tuned large language model as a stylizer, allowing the model to rewrite sentences in a target style while preserving meaning. Experiments across four style domains show that RT‑SFT surpasses state‑of‑the‑art approaches, including few‑shot in‑context learning, and offers effective retrieval augmentation for expert style domains with strict terminology.

By Ruoxi Liu, Philipp Koehn