Reading Working Papers in Linguistics 4 (2000) - The University of ...

I. SINKA, M. GARMAN AND C. SCHELLETTER
development, in the form of the category of main verbs. We concentrate on
main verbs, as opposed to auxiliaries (Aux), because
(1) Aux is a closed class intimately linked to the grammatical system;
(2) Aux is not easy to compare across English, German and Latvian;
(3) Aux is later in development than our early samples.
The framework for our investigation is the lexical profiling approach
developed in Garman (1995) which provides a format for displaying
quantitative and qualitative aspects of the full vocabulary of expressive
language samples. Among other measures, the lexical profile provides typetoken
ratios (TTRs) for these form classes, as well as the more traditional TTR
for the whole vocabulary. To control for effect on TTR of sample size
(Richards 1987), this profile uses fixed (and rather small) size samples that are
realistic within a clinical linguistic context - 250 continuous word tokens.
This approach has revealed certain developmental patterns for English
children, based partly on a re-analysis of the MRC Project data (Fletcher et al.
1986). Two of these expectations are:
(1) contrary to earlier findings (Fletcher & Garman 1988), language normal
children show significant TTR development between the ages of 3 to 7 years,
for both whole-sample vocabulary (TTR) and main verb vocabulary (VTTR);
(2) there is a tendency for VTTR to approximate whole-sample TTR, for each
age group (and similar patterns have been found in adult data).
The data from Sonja and Maija should give us an insight into how verb
vocabulary develops in relation to grammatical development considerably
before 3 years, and how English, German and Latvian compare in this respect.
It should also provide specific information on how far early bilinguals show
separate development of their two languages (De Houwer 1990).
2. Method
2.1 Data
Tables 1a and 1b show the sampling distribution. Sessions were targeted on
specific participants/languages, and relatively few non-target or mixed
utterances were elicited.
For Sonja, practical difficulties meant that sampling in English was less
continuous through the observation period than for German. Each child had
equivalent, and considerable, exposure to each language.
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