Robert Daland, UCLA

What's in "the input"? A comparison of ADS and CDS

It has been claimed that child-directed speech differs from spontaneous adult-directed speech at multiple levels, possibly in a way that might facilitate language acquisition. There is now considerable cross-linguistic evidence of ADS/CDS differences at the phonetic level. However, only one study, Lee & Davis (2008), have examined differences at the phonological level. The present work addresses this issue by considering a variety of phonological distributions, both in adult-directed speech, and in a corpus of speech uttered in the presence of a child.

METHOD: The CELEX dictionary was used to obtain phonological information from adult- and child-input corpora. Various type and token distributions were collected, including stress pattern, CV structure, word-initial and -final segmental, place, and manner distributions.

RESULTS AND DISCUSSION: A conspicuously large number of statistically significant differences were found, some in accord with previous findings by Lee & Davis (2008), and some in the opposite direction. It is argued that many of the significant differences do not reflect true *genre* differences, and rather arise from inappropriate assumptions of the language model.