A corpus-based analysis of lexical diversity (TTR) in fourth-year Uzbek EFL students’ essays

Abstract

Vocabulary knowledge plays a crucial role in developing writing proficiency in a second language. Among various lexical measures, lexical diversity is widely used to evaluate learners’ vocabulary range in written production. This study examines lexical diversity in IELTS Task 2 essays written by fourth-year Uzbek EFL students using a corpus-based approach. A small learner corpus consisting of 10 essays, each containing a minimum of 250 words, was compiled and analyzed. Lexical diversity was measured using the Type-Token Ratio (TTR). The corpus was processed using AntConc software to determine the total number of word tokens and unique word types. The analysis revealed a moderate level of lexical diversity with a TTR score of 0.29. This result indicates that students are able to use a relatively varied vocabulary in their academic writing, although the repetition of high-frequency lexical items remains noticeable. The findings contribute to a better understanding of vocabulary use in Uzbek EFL academic writing and highlight the importance of continued vocabulary development even at advanced stages of language learning.