PLaMo 2 Technical Report
Preferred Networks, :, Kaizaburo Chubachi, Yasuhiro Fujita, Shinichi Hemmi, Yuta Hirokawa, Toshiki Kataoka, Goro Kobayashi, Kenichi Maehashi, Calvin Metzger, Hiroaki Mikami, Shogo Murai, Daisuke Nishino, Kento Nozawa, Shintarou Okada, Daisuke Okanohara, Shunta Saito, Shotaro Sano, Shuji Suzuki, Daisuke Tanaka, Avinash Ummadisingu, Hanqin Wang, Sixue Wang, Tianqi Xu
公開日: 2025/9/5
Abstract
In this report, we introduce PLaMo 2, a series of Japanese-focused large language models featuring a hybrid Samba-based architecture that transitions to full attention via continual pre-training to support 32K token contexts. Training leverages extensive synthetic corpora to overcome data scarcity, while computational efficiency is achieved through weight reuse and structured pruning. This efficient pruning methodology produces an 8B model that achieves performance comparable to our previous 100B model. Post-training further refines the models using a pipeline of supervised fine-tuning (SFT) and direct preference optimization (DPO), enhanced by synthetic Japanese instruction data and model merging techniques. Optimized for inference using vLLM and quantization with minimal accuracy loss, the PLaMo 2 models achieve state-of-the-art results on Japanese benchmarks, outperforming similarly-sized open models in instruction-following, language fluency, and Japanese-specific knowledge.