Child language with mother and with stranger at home and in the laboratory: a methodological study.

This methodological study in 33 two-year-olds shows that child speech (total utterances, word roots, MLU) occurs at about the same level in different settings (the familiar home vs. the unfamiliar laboratory), but that children speak more and in more differentiated ways with different people (mother vs. stranger). Child speech also shows significant short-term stability. Girls use more different word roots and speak in longer utterances than do boys. In spontaneous child speech, cross-context generalizations appear warranted, but they also depend on conversational partner and gender of child.