AVERAGE C-UNIT LENGTHS IN THE DISCOURSE OF AFRICAN-AMERICAN CHILDREN FROM LOW-INCOME, URBAN HOMES

This investigation reports average length of communication units (C-un its) in words and in morphemes For 95 4- to 6 1/2-year-old African Ame rican boys and girls from lower-income homes in metropolitan Detroit. Mean C-units increased across the age span of this sample, and kinderg artners produced significantly longer C-units than preschoolers. The s yntactic complexity of the children's language samples correlated posi tively with increases in C-unit length, and regression analyses reveal ed that syntactic complexity was the best predictor of mean C-unit len gth. Children with longer average C-unit lengths produced greater freq uencies of: all types of syntactic complexity. Their language samples were distinguished from children with shorter mean C-unit lengths by c lauses linked with coordinate and subordinate conjunctions. The findin gs indicate that average C-unit length will be useful as a quantitativ e index of linguistic growth in research designs focusing on young sch ool-age African American children living in poverty.