A Corpus-Based Study of Phoneme Distribution in Thai

This paper presents steps in accessing Thai phoneme distribution from large-scale written Thai corpora. The data were from 12 text genres from InterBEST [1], considered the biggest Thai corpora. Each word was transliterated using the grapheme-to-phoneme software [2]. Then, frequency of words, frequency of 81 Thai phonemes in each genre, and the 95% CIs of average occurrences of each phoneme were calculated. Phonemes from any genre that did not fall within the 95% CI were counted. As a result, 3 genres whose distributions are highly incompatible with others were removed, resulting in the remaining of approximately 80% of the data. Finally, we obtained phoneme distribution of initials, finals, vowels, and tones. Importantly, 4 bigram frequencies (final-to-tone, vowel-to-final, initial-totone, and initial-to-vowel) and a trigram frequency (vowel-final-tone) were also given.