Neighborhood density and word frequency predict vocabulary size in toddlers.
OBJECTIVE
To document the lexical characteristics of neighborhood density (ND) and word frequency (WF) in the lexicons of a large sample of English-speaking toddlers.


METHODS
Parents of 222 British-English-speaking children aged 27(+/-3) months completed a British adaptation of the MacArthur-Bates Communicative Development Inventory: Words and Sentences (MCDI; Klee & Harrison, 2001). Child words were coded for ND and WF, and the relationships among vocabulary, ND, and WF were examined. A cut-point of -1 SD below the mean on the MCDI classified children into one of two groups: low or high vocabulary size. Group differences on ND and WF were examined using nonparametric statistics.


RESULTS
In a hierarchical regression, ND and WF accounted for 47% and 14% of unique variance in MCDI scores, respectively. Low-vocabulary children scored significantly higher on ND and significantly lower on WF than did high-vocabulary children, but there was more variability in ND and WF for children at the lowest points of the vocabulary continuum.


CONCLUSIONS
Children at the lowest points of a continuum of vocabulary size may be extracting statistical properties of the input language in a manner quite different from their more able age peers.
Curtin University of Technology, Perth, Australia. stephanie.stokes@canterbury.ac.nz
Stephanie F
SF
Stokes
D002663:Child Language; D002675:Child, Preschool; D003627:Data Interpretation, Statistical; D004739:England; D005260:Female; D006801:Humans; D007223:Infant; D007802:Language; D007807:Language Tests; D008037:Linguistics; D008297:Male; D012044:Regression Analysis; D014825:Vocabulary