ChildSpeaksR Documentation



Age at first speaking and aptitude test scores


A dataset with 21 observations on the following 3 variables.

Child ID for each child
Age Age at first speaking (in months)
Gesell Gesell Aptitude Test Score


The data are from a study about whether there is a relationship between the age at which a child first speaks (in months) and his or her score on a Gesell Aptitude Test taken later in childhood.


These data were originally collected by L.M. Linde of UCLA but were first published by M.R. Mickey, O.J. Dunn, and V. Clark, "Note on the use of stepwise regression in detecting outliers," Computers and Biomedical Research, 1 (1967), pp. 105-111. The data have been used by several authors. We found them in David Moore's Basic Practice of Statistics, WH Freeman (2004)