Indices of lexical diversity have been used to estimate the size of a writer's vocabulary and/or a writer's lexical proficiency for some time. One issue with many commonly used indices of lexical diversity (e.g., TTR and index) is that they vary as a function of text length. Accordingly, much research has been devoted to the development of indices…

Lexical items that are encountered more frequently and in varying contexts have important effects on second language (L2) development because frequent and contextually diverse words are learned faster and become more entrenched in a learner's lexicon (Ellis 2002a, b). Despite evidence that L2 learners are generally exposed to non-native input,…

A number of longitudinal studies of L2 production have reported frequency effects wherein learners' produce more frequent words as a function of time. The current study investigated the spoken output of English L2 learners over a four-month period of time using both native and non-native English speaker frequency norms for both word types and word…