The relationship between reading proficiency and vocabulary size: An empirical investigation

Abstract

Studies of the vocabulary size needed to be a proficient second-language reader commonly arrive at numbers that are staggering. The figures most often cited are between 8,000 and 9,000 words, as required for reading novels and newspaper articles with sufficient ease and understanding (Nation, 2006). To date, almost all of the empirical research on reading proficiency and vocabulary size has focused on English, but two recent studies (Hacking & Tschirner, 2017; Hacking, Tschirner, & Rubio, in press) reported lexical minimums associated with particular American Council on the Teaching of Foreign Languages (ACTFL) reading proficiency levels. This chapter builds on these data and examines the relationship between the reading proficiency and vocabulary knowledge of L2 learners of German, Russian, and Spanish. It addresses the following research questions: (1) How well does reading proficiency as defined by ACTFL predict vocabulary size measured as the receptive knowledge of various bands of the most frequent 5,000 words in German, Russian, and Spanish? (2) What vocabulary sizes are predicted by ACTFL reading proficiency levels? (3) Do German, Russian, and Spanish differ with respect to the relationship between reading proficiency and vocabulary size? This chapter will also focus on some implications for curriculum development.