Cross-Lingual English–Urdu Semantic Word Similarity Using Sentence Transformers

Semantic word similarity is a quantitative method of determining how much two terms are contextually identical, which is a considerable challenge for computational linguistics. The research community has examined a range of approaches to address this issue. However, most of these approaches are for a comparatively limited set of languages, especially English. Research on semantic word similarity for South Asian languages, particularly Urdu, is immature. In recent years, transformer-based approaches have proved extremely successful for a range of language processing tasks. The primary aim of this study is to develop and compare a variety of transformer-based approaches to the cross-lingual English–Urdu semantic word similarity task. This study evaluated a publicly available benchmark USWS-19 corpus that comprises 518 word pairs. This study mainly explored four types of transformer-based approaches: (a) cross-lingual sentence transformer-based approaches using the original dataset, (b) cross-lingual sentence transformer-based approaches using the translated dataset (translation plus monolingual analysis [T+MA] approach), (c) the feature fusion approach (mixture of features), and large language models. In addition, this study also explores the word embedding-based approach using the translated dataset (T+MA approach). In total, this study developed 29 transformer-based models, with the highest results (Pearson correlation = 0.788) achieved using a feature fusion approach, that is, Best-Two-SBERT (where SBERT stands for sentence-bidirectional encoder representations from transformers; using T+MA) + BEST Baseline (with Bing translator) + Best cross-lingual SBERT. This approach improved by 7% over previously reported results on the same corpus.