Share What You Already Know: Cross-Language-Script Transfer and Alignment for Sentiment Detection in Code-Mixed Data
Niraj Pahari, Kazutaka Shimada
TL;DR
This work tackles sentiment analysis for code-mixed text written in different scripts by preserving script-specific pre-trained knowledge and enabling cross-language-script transfer. A three-component architecture employs script-specific encoders, cross-attention for cross-language sharing, and Earth Mover's Distance-based alignment plus regularization to align representations without losing script-specific semantic content. Experiments on Nepali-English and Hindi-English romanized datasets show the proposed method outperforms strong baselines, with ablations confirming the value of alignment and regularization, and SHAP analyses providing interpretability of cross-script knowledge sharing. The results suggest that cross-language-script transfer is a promising direction for code-mixed NLP and highlights the importance of data cleaning and robust transliteration for further gains.
Abstract
Code-switching entails mixing multiple languages. It is an increasingly occurring phenomenon in social media texts. Usually, code-mixed texts are written in a single script, even though the languages involved have different scripts. Pre-trained multilingual models primarily utilize the data in the native script of the language. In existing studies, the code-switched texts are utilized as they are. However, using the native script for each language can generate better representations of the text owing to the pre-trained knowledge. Therefore, a cross-language-script knowledge sharing architecture utilizing the cross attention and alignment of the representations of text in individual language scripts was proposed in this study. Experimental results on two different datasets containing Nepali-English and Hindi-English code-switched texts, demonstrate the effectiveness of the proposed method. The interpretation of the model using model explainability technique illustrates the sharing of language-specific knowledge between language-specific representations.
