From General LLM to Translation: How We Dramatically Improve Translation Quality Using Human Evaluation Data for LLM Finetuning

AbstractIn this paper, we present the methodology employed by the NLP team at Yandex LLC for participating in the WMT 2024 General MT Translation track, focusing on English-to-Russian translation. Our approach involves training a YandexGPT LLM-based model for translation tasks using a multi-stage process to ensure high-quality and contextually accurate translations.Initially, we utilize a pre-trained model, trained on a large corpus of high-quality monolingual texts in various languages, crawled from various open sources, not limited to English and Russian. This extensive pre-training allows the model to capture a broad spectrum of linguistic nuances and structures. Following this, the model is fine-tuned on a substantial parallel corpus of high-quality texts collected from diverse open sources, including websites, books, and subtitles. These texts are meticulously aligned at both the sentence and paragraph levels to enhance the model’s contextual understanding and translation accuracy.In the subsequent stage, we employ p-tuning on an internal high-quality corpus of paragraph-aligned data. This step ensures that the model is finely adjusted to handle complex paragraph-level translations with greater fluency and coherence.Next, we apply the Contrastive Pretraining Objective (CPO) method, as described in the paper CPO, using a human-annotated translation corpus. This stage focuses on refining the model’s performance based on metrics evaluated at the paragraph level, emphasizing both the accuracy of the translation and the fluency of the resulting texts. The CPO method helps the model to better distinguish between subtle contextual differences, thereby improving translation quality.In the final stage, we address the importance of preserving the content structure in translations, which is crucial for the General MT test set. To achieve this, we introduce a synthetic corpus based on web pages and video subtitles, and use it during HE markup finetune training. This encour