Parameter setting in language acquisition

In the present study, I examine the production of null objects and the occurrence of the ba construction with 47 monolingual Mandarin-speaking children (aged 1;2 - 6;5) and their caregivers recorded in the CHILDES database, in order to assess the triggering model (Gibson & Wexler, 1994) and the variational model (Yang, 2002, 2004). The results indicate that whether measured by the acquisition of a null object grammar or by the ba construction, no gradual climb was found in the children's developmental pattern as anticipated by the variational model, rather parametric change was precipitous as expected on the triggering model.