The measurement of second language (L2) productive lexical proficiency has driven a great deal of research over the past two decades. Research has indicated that more proficient speakers and writers tend to use a wider range of words and that more proficient writers tend to use words that are more sophisticated (less frequent in reference…

In the realm of language proficiency assessments, the domain description inference and the extrapolation inference are key components of a validity argument. Biber et al.'s description of the lexicogrammatical features of the spoken and written registers in the T2K-SWAL corpus has served as support for the TOEFL iBT test's domain description and…

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…

A key piece of a validity argument for a language assessment tool is clear overlap between assessment tasks and the target language use (TLU) domain (i.e., the domain description inference). The TOEFL 2000 Spoken and Written Academic Language (T2K-SWAL) corpus, which represents a variety of academic registers and disciplines in traditional…

Over the past 45 years, the construct of syntactic sophistication has been assessed in L2 writing using what Bulté and Housen (2012) refer to as absolute complexity (Lu, 2011; Ortega, 2003; Wolfe-Quintero, Inagaki, & Kim, 1998). However, it has been argued that making inferences about learners based on absolute complexity indices (e.g., mean…

This study investigates relations between second language (L2) lexical input and output in terms of word information properties (i.e., lexical salience; Ellis, 2006a). The data for this study come from a longitudinal corpus of naturalistic spoken data between L2 learners and first language (L1) interlocutors collected over a year's time. The…

This study investigates the potential for linguistic microfeatures related to length, complexity, cohesion, relevance, topic, and rhetorical style to predict L2 writing proficiency. Computational indices were calculated by two automated text analysis tools (Coh- Metrix and the Writing Assessment Tool) and used to predict human essay ratings in a…