Lexical Diversity and Language Development Quantification and Assessment [Hardcover]

Vocabulary richness, including lexical diversity and use of rare words, has an important role in assessing proficiency, diagnosing progress and testing theory in the study of language development. This book reviews different methods for quantifying how vocabulary is deployed in spontaneous speech and writing, before introducing an alternative approach which can assess overall lexical diversity, measure morphology development and compare the development of different word classes. The new approach is illustrated by its application to first and second language learners.List of Tables List of Figures Acknowledgements PART I: MEASURING LEXICAL DIVERSITY Introduction Some Approaches to Measuring Lexical Diversity A Mathematical Model of Lexical Diversity PART II: VALIDATION OF THE MODEL THROUGH ITS APPLICATION TO LANGUAGE CORPORA Early Child Language 1: The New England Corpus Early Child Language 2: The Bristol Corpus Lexical Diversity and the Investigation of Accommodation in Foreign Language Proficiency Interviews A New Measure of Inflectional Diversity and its Application to English and Spanish Date Sets PART III: DIFFERENT WORD CATEGORIES AND THEIR DIVERSITY: TYPE-TYPE VERSUS TYPE-TOKEN Comparing the Diversity of Lexical Categories: The Type/Type Ratio and Related Measures Lexical Diversity and Lexical Sophistication in First Language Writing PART IV: CONCLUSION Overview and Conclusions Notes Glossary of Technical Terms and Acronyms Appendices Index

'This book represents a major contribution to the study of both lexical diversity and language development... [and] provides the most comprehensive and compelling study available to date of vocabulary measurement, including type-token ratios, number of different words, and word length. The innovative, empirically validated, and user-friendly measure of lexical diversity (VOCD - or simply D) that it proposes is based on deep understanding of mathematical models combined with rich background in language acquisition alƒ*