On the Non-uniqueness of Acoustic-to-Articulatory Mapping
Daniel Neiberg, G. Ananthakrishnan · 2008
This paper studies the hypothesis that the acoustic-to-articulatory mapping is nonunique, statistically. The distributions of the acoustic and articulatory spaces are obtained by minimizing the BIC while fitting the data into a GMM using the EM algorithm. The kurtosis is used to measure the non-Gaussianity of the distributions and the Bhattacharya distance is used to find the difference between distributions of the acoustic vectors producing nonunique articulator configurations. It is found that stop consonants and alveolar fricatives are generally not only non-linear but also nonunique, while dental fricatives are found to be highly non-linear but fairly unique.