Language proficiency testing serves an important function of classifying examinees into different categories of ability. However, misclassification is to some extent inevitable and may have important consequences for stakeholders. Recent research suggests that classification efficacy may be enhanced substantially using computerized adaptive…

The present study discusses the relevance of measures of lexical diversity (LD) to the assessment of learner corpora. It also argues that existing measures of LD, many of which have become specialized for use with language corpora, are fundamentally measures of lexical repetition, are based on an etic perspective of language, and lack construct…