wh-questions with auxiliary inversion, propositional complements, conjoined sentences) as complex patterns over parse trees, we propose that child language development can instead be measured automatically in a way that is fully data-driven and can be applied to many languages for which accurate dependency parsers are available, without relying on carefully constructed lists of grammatical structures or complex syntactic patterns in each language.
we examine two hypotheses: (1) counts of features extracted from syntactic parse trees using only simple templates are at least as expressive of changes in language development as the Index of Productive Syntax (Scarborough, 1990), an empirically validated metric based on an inventory of grammatical structures derived from the child language literature; and (2) these parse tree features can be used to model language development without the use of an inventory of specific structures, assuming only the knowledge that in typically developing children the level of language development is correlated with age.