This study explored how Vietnamese IELTS learners perceived IELTS Writing Task 2, particularly their lexical self-efficacy, and how they displayed their lexical resource in their IELTS Task 2 writing performance in four dimensions: lexical density, lexical sophistication, lexical variation, and lexical accuracy.
Data were collected from numerous IELTS classes in a city in central Vietnam. In total, 200 IELTS learners completed a questionnaire about their perceptions of the IELTS test, IELTS Writing Task 2, and their lexical self-efficacy. Eighty-six of them wrote two IELTS Writing Task 2 essays in their normal IELTS classroom hours on ready-made paper sheets in 50 minutes; Essay 1 was about the topic of living overseas and Essay 2 about community work. The time interval between the essays was one week and in counterbalanced design. The collected written scripts were analysed for:
- Lexical density, lexical diversity and lexical sophistication using 26 measures derived from the same computational system Lexical Complexity Analyzer (LCA) (Lu, 2012).
- Their relationship with the quality of the writing performance as graded by the IELTS examiners arranged by IDP IELTS.
- Lexical accuracy (lexical errors), and the link between erroneous use and the IELTS Writing Task 2 performance.
The questionnaire findings show that learners were motivated to learn IELTS for different reasons, (eg, enhancing general language proficiency, getting ideal jobs and seeking foreign scholarships), and for its accessibility and credibility. They reported topic unfamiliarity was a major inhibiting task-related factor, and writing with appropriate and varied vocabulary was linguistically challenging for them, and so was lexical cohesion. The learners also identified different sources of anxiety involved in writing IELTS Task 2, of which self-oriented anxiety about time pressure and the performance quality was most intense. Notable was their reported confidence in using different parts of speech of lexical words, though their perceived self-efficacy was particularly low with regards to spelling lexical words correctly, and using low frequency words in their writing. Learners’ perceptions of their ability to vary their lexical use through on-topic words, synonyms/antonyms and specific words for a general concept were mixed with different levels of self-efficacy. No significant correlations were found between perceived anxiety and writing performance, yet lexical self-efficacy had a significant weak correlation with the writing performance.
With regards to performance-based lexical resource, the study found an effect for the writing tasks/topics on the quantitative measures of lexical richness and their relationship with the writing performance graded by IELTS raters. Generally, the writing task about community work elicited denser, more sophisticated and more varied vocabulary than writing about living overseas. However, task influence was subject to the particular indices used to measure lexical sophistication and lexical variation. The findings also revealed that lexical variation was more strongly correlated with the writing performance than lexical density and lexical sophistication. Learners reported the latter topic was more challenging, even though there was no significant difference in the band scores between the two essays. The learners perceived the difficulty of the writing tasks in terms of topic novelty or familiarity that restricted or facilitated access to ideas and vocabulary to write.
The Vietnamese IELTS learners in the present study also committed lexical errors of different types, of which misspellings, misuse of verb forms, collocations, noun inflections and word choice were most common in both essays. The writing tasks/topics did not have an effect on major error types except misspellings of general words. Lexical errors correlated negatively with the writing performance, and the correlations were weak to moderate.
The study offers important implications for IELTS, IELTS teachers and IELTS learners and for future research with regards to how to prepare learners for IELTS Writing Task 2 and how to measure lexical resource/richness.