This dissertation presents a series of case studies concerned with whether the signal in a given set of measurements that we take in the course of linguistic inquiry reflects grammatical competence or performance factors. We know that performance and competence do not always covary, yet it is not uncommon to assume that measurements that we take…

Language documentation efforts are most often concerned with the adult language and usually do not include the language used by and with children. Essential parts of the natural linguistic behaviour of communities thus remain undocumented, and a growing body of literature explores what language documentation, language maintenance, and language…

The 'root infinitive' phenomenon in child speech is known from major languages such as Dutch. In this case study, a child acquiring the Papuan language Nungon in a remote village setting in Papua New Guinea uses two different non-finite verb forms as predicates of main clauses ('root' contexts) between ages 2;3 and 3;3. The first root non-finite…

It has long been recognized that there is a natural dependence between theories of knowledge representation and theories of knowledge acquisition, with the idea that the right knowledge representation enables acquisition to happen as reliably as it does. Given this, a reasonable criterion for a theory of knowledge representation is that it be…

This study examines the "ba" and "bei" constructions in Mandarin using data from the Tong corpus, a new multimedia longitudinal child language corpus. A unified aspectual account of the two constructions is proposed: both require telic predicates, and should thus correlate with the perfective rather than imperfective aspect for…

Generative approaches to language have long recognized the natural link between theories of knowledge representation and theories of knowledge acquisition. The basic idea is that the knowledge representations provided by Universal Grammar enable children to acquire language as reliably as they do because these representations highlight the…

This article demonstrates how the Comparative Method can be applied to cross-linguistic research on language acquisition. The Comparative Method provides a systematic procedure for organizing and interpreting acquisition data from different languages. The Comparative Method controls for cross-linguistic differences at all levels of the grammar and…

What are the sources of variation in the input, and how much do they matter for language acquisition? This study examines frequency variation in manner-of-articulation classes in child and adult input. The null hypothesis is that segmental frequency distributions of language varieties are unigram (modelable by stationary, ergodic processes), and…

While acquisition of more than one language from birth is a relatively common phenomenon, whether children under two years of age use their languages in a differentiated manner has not yet been established. The current study investigates the pragmatic differentiation of a child who lives in Australia and was acquiring two minority languages,…

An area in need of study in child language acquisition is that of complex multilingual contexts in which there is little language separation by interlocutor or domain. Little is known about how multilingual children use language to construct their identities in each language or in both languages. Identity construction in monolingual contexts has…

Major innovations are becoming available for research in language development and disorders. Among these innovations, recent tools allow naturalistic recording in children's homes and automated analysis to facilitate representative sampling. This study employed all-day recordings during the 2nd year of life in a child exposed to three languages,…

Current views on the acquisition of PRO can roughly be divided into two areas: lexical and syntactic accounts. We present data on one verb, "decide," that yields data that not only differs from the data for other similar verbs with the same children, but does not lend itself easily to either type of account. Data from a sentence elicitation task…

An analysis was made of the correspondence between intonation and the larger and smaller movements accompanying two-syllable and longer utterances. Synchrony between peaks of intonation and movement pattern was found and is used to argue for a performative basis for early two-word productions. (Author/EJS)

A case study of a 2-year-old progressing normally in speech development provides evidence of suprasegmental marking of the plural, thought to be adopted only in language-impaired children. Acoustic analyses of the durations and intensity of elicited words indicate that the child had adopted a suprasegmental strategy for marking the singular/plural…

Describes one child's early productions of lexical primary stress, using as a framework the following questions: (1) Is conventional stress used consistently? (2) Are there other alternatives for the placement of primary stress? (3) Does stress assignment appear to be random? (4) Does stress assignment appear to vary with spontaneous vs. imitative…