Word-level Language Identification in Bi-lingual Code-switched Texts

Code-switching is the practice of moving back and forth between two languages in spoken or written form of communication. In this paper, we address the problem of word-level language identification of code-switched sentences. Here, we primarily consider Hindi-English (Hinglish) code-switching, which is a popular phenomenon among urban Indian youth, though the approach is generic enough to be extended to other language pairs. Identifying word-level languages in code-switched texts is associated with two major challenges. Firstly, people often use non-standard English transliterated forms of Hindi words. Secondly, the transliterated Hindi words are often confused with English words having the same spelling. Most existing works tackle the problem of language identification using n-grams of characters. We propose some techniques to learn sequence of character(s) frequently substituted for character(s) in standard transliterated forms. We illustrate the superior performance of these techniques in identifying Hindi words corresponding to the given transliterated forms. We adopt a novel experimental model which considers the language and part-of-speech of adjoining words for word-level language identification. Our test results show that the proposed model significantly increases the accuracy over existing approaches. We achieved F1-score of 98.0% for recognizing Hindi words and 94.8% for recognizing English words.