title: How to measure the onset of babbling reliably?
abstract: Various measures for identifying the onset of babbling have been proposed in the literature, but a formal definition of the exact procedure and a thorough validation of the sample size required for reliably establishing babbling onset is lacking. In this paper the reliability of five commonly used measures is assessed using a large longitudinal corpus of spontaneous speech from forty infants (age 0 ; 6-2 ; 0). In a first experiment it is shown that establishing the onset of babbling with reasonable (95%) confidence is impossible when the measures are computed only once, and when the number of vocalizations are not equal for all children at all ages. In addition, each measure requires a different minimal sample size. In the second experiment a robust procedure is proposed and formally defined that permits the identification of the onset of babbling with 95% confidence. The bootstrapping procedure involves extensive resampling and requires relatively few data.
authors: University of Antwerp.
authors: Inge
authors: I
authors: Molemans
authors: Renate
authors: R
authors: van den Berg
authors: Lieve
authors: L
authors: van Severen
authors: Steven
authors: S
authors: Gillis
mesh_terms: D000367:Age Factors; D002663:Child Language; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D013060:Speech; D014741:Video Recording