Entropy as a measure of mixedupness of realizations in child speech

Elena Babatsouli 1 , David Ingram 2  and Dimitrios A. Sotiropoulos 3
  • 1 Institute of Monolingual and Bilingual Speech, Chania
  • 2 Arizona State University, Tempe
  • 3 Technical University of Crete, Chania
Elena Babatsouli, David Ingram and Dimitrios A. Sotiropoulos


Typical morpho-phonological measures of children’s speech realizations used in the literature depend linearly on their components. Examples are the proportion of consonants correct, the mean length of utterance and the phonological mean length of utterance. Because of their linear dependence on their components, these measures change in proportion to their component changes between speech realizations. However, there are instances in which variable speech realizations need to be differentiated better. Therefore, a measure which is more sensitive to its components than linear measures is needed. Here, entropy is proposed as such a measure. The sensitivity of entropy is compared analytically to that of linear measures, deriving ranges in component values inside which entropy is guaranteed to be more sensitive than the linear measures. The analysis is complemented by computing the entropy in two children’s English speech for different categories of word complexity and comparing its sensitivity to that of linear measures. One of the children is a bilingual typically developing child at age 3;0 and the other child is a monolingual child with speech sound disorders at age 5;11. The analysis and applications demonstrate the usefulness of the measure for evaluating speech realizations and its relative advantages over linear measures.

  • Babatsouli, E. 2016. “Added syllable complexity in a child’s developmental speech and clinical implications”. Clinical Linguistics and Phonetics 1464–5076. (doi:).

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  • Babatsouli, E. 2015. “Technologies for the study of speech: Review and an application” [Special Issue on Language Disorders and ICT]. Themes in Science and Technology Education 8(1). 17–32.

  • Babatsouli, E., D. Ingram and D. Sotiropoulos. 2014. “Phonological word proximity in child speech development”. Chaotic Modeling and Simulation. 4(3). 295–313.

  • Brown, R. 1973. A first language: The early stages. Cambridge, MA: Harvard University Press.

  • Bunta, F., L. Fabiano-Smith, B.A. Goldstein and D. Ingram. 2009. “Phonological whole-word measures in three-year-old bilingual children and their age-matched monolingual peers”. Clinical Linguistics and Phonetics. 23. 156–175.

  • Burrows, L. and B.A. Goldstein. 2010. “Whole word measures in bilingual children with speech sound disorders”. Clinical Linguistics and Phonetics. 24. 357–368.

  • Goldsmith, J. 2000. “On information theory, entropy, and phonology in the 20th century”. Folia Linguistica XXXIV(1–2). 85–100.

  • Ingram, D. 1981. Procedures for the phonological analysis of children’s language. Baltimore, MD: University Park Press.

  • Ingram, D. 2002. “The measurement of whole-word production”. Journal of Child Language. 29. 713–733.

  • Ingram, D. 2015. “Whole-word measures: Using the pCC-PWP intersect to distinguish speech delay from speech disorder”. In: Bowen, C. (ed.), Children’s speech sound disorders (2nd edition). Oxford, UK: John Willey & Sons. 100– 104.

  • Ingram, D. and K. Ingram. 2001. “A whole-word approach to phonological analysis and intervention”. Language, Speech and Hearing Services in Schools. 32. 271– 283.

  • Ingram, D., L. Williams and N. J. Scherer. 2015. “Are speech sound disorders phonological or articulatory? A spectrum approach”. In E. Babatsouli and D. Ingram (eds.), Proceedings of the International Symposium on Monolingual and Bilingual Speech 2015. ISBN 978-618-82351-0-6. Retrieved at www.ismbs.eu/publications. 98–104.

  • Macleod, A.A., K. Laukys and S. Rvachew. 2011. “The impact of bilingual language learning on whole-word complexity and segmental accuracy among children aged 18 and 36 months”. International Journal of Speech and Language Pathology. 13. 490–499.

  • MacWhinney, B. 2000. The CHILDES project: tools for analyzing talk (3rd ed.). Mahwah, NJ: Lawrence Erlbaum.

  • Nespor, M., M. Peña and J. Mehler. 2003. “On the different roles of vowels and consonants in speech processing and language acquisition”. Lingue e Linguaggio. 2. 203–229.

  • Nice, M. M. 1925. “Length of sentences as a criterion of a child’s progress in speech”. Journal of Educational Psychology. 16. 370–379.

  • Parker, M.D. and K. Brorson. 2005. “A comparative study between mean length of utterance in morphemes (MLUm) and mean length of utterance in words (MLUw)”. First Language. 25. 365–376.

  • Schmitt, L.S., B.H. Howard and J.F Schmitt. 1983. “Conversational speech sampling in the assessment of articulation proficiency”. Language, Speech, and Hearing Services in Schools. 14. 210–214.

  • Shriberg, L., D. Austin, B. Lewis, J. McSweeney and D. Wilson. 1997. “The percentage of consonants correct (PCC) metric: Extensions and reliability data”. Journal of Speech, Language, and Hearing Research. 3. 708–722.

  • Shannon, C.E. 1948a. A mathematical theory of communication. Bell System Technical Journal. 27(3). 379–423.

  • Shannon, C.E. 1948b. “A mathematical theory of communication”. Bell System Technical Journal. 27(4). 623–656.

  • Taelman, H., G. Durieux and S. Gillis. 2005. “Notes on Ingram’s whole-word measures for phonological development”. Journal of Child Language. 32. 391– 400.

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Poznan Studies in Contemporary Linguistics publishes high-quality articles representative of theory-based empirical research in contemporary synchronic linguistics and interdisciplinary studies of language from various perspectives. The journal serves as a forum for modern developments and trends in linguistics, with contributions from the world’s leading linguistic labs.