Appropriateness as an aspect of lexical richness: what do quantitative measures tell us about children's writing?

This is the final version. Available on open access from Elsevier via the DOI in this recordQuantitative measures of vocabulary use have added much to our understanding of first and second language writing development. This paper argues for measures of register appropriateness as a useful addition to these tools. Developing an idea proposed by Author (2019), it explores what such measures can tell us about vocabulary development in the L1 writing of school children in England and critically examines how results should be interpreted. It shows that significant patterns of discipline- and genre-specific vocabulary development can be identified for measures related to four distinct registers, though the strongest patterns are found for vocabulary associated with fiction and academic writing. Follow-up analyses showed that changes across year groups were primarily driven, not by the nature of individual words, but by the overall quantitative distribution of register-specific vocabulary, suggesting that the traditional distinction between measures of lexical diversity and lexical sophistication may not be helpful for understanding development in this context. Closer analysis of academic vocabulary showed development of distinct vocabularies in Science and English writing in response to sharply differing communicative needs in those disciplines, suggesting that development in children’s academic vocabulary should not be seen as a single coherent process.Economic and Social Research Council (ESRC