Shiksha: A Technical Domain focused Translation Dataset and Model for Indian Languages
Advait Joglekar, Srinivasan Umesh
TL;DR
The paper tackles the problem of neural machine translation for Indian languages in scientific, technical, and educational domains by constructing Shiksha, a large domain-specific parallel corpus sourced from NPTEL transcripts. It combines meticulous data extraction, regex-based cleaning, and LABSE-guided bitext mining (via SentAlign) to produce roughly 2.8 million sentence-pairs across 8 English–Indic and 28 Indic–Indic pairs. A base multilingual model (NLLB-200 3.3B) is fine-tuned with LoRA using three strategies, with the best approach achieving strong in-domain gains and better generalization on Flores+ benchmarks, approaching IndicTrans2 performance. The work also introduces Translingua, a tool enabling faster, higher-quality subtitle translations, and highlights the importance of domain-specific data for improving NMT in low-resource languages, while acknowledging limitations and the need for broader domain coverage and human evaluation.
Abstract
Neural Machine Translation (NMT) models are typically trained on datasets with limited exposure to Scientific, Technical and Educational domains. Translation models thus, in general, struggle with tasks that involve scientific understanding or technical jargon. Their performance is found to be even worse for low-resource Indian languages. Finding a translation dataset that tends to these domains in particular, poses a difficult challenge. In this paper, we address this by creating a multilingual parallel corpus containing more than 2.8 million rows of English-to-Indic and Indic-to-Indic high-quality translation pairs across 8 Indian languages. We achieve this by bitext mining human-translated transcriptions of NPTEL video lectures. We also finetune and evaluate NMT models using this corpus and surpass all other publicly available models at in-domain tasks. We also demonstrate the potential for generalizing to out-of-domain translation tasks by improving the baseline by over 2 BLEU on average for these Indian languages on the Flores+ benchmark. We are pleased to release our model and dataset via this link: https://huggingface.co/SPRINGLab.
