2026-09-22T19:06:24Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/129522 2026-02-05 col_2142_5131 col_2142_13736 com_2142_5130 com_2142_8975 com_2142_8903

application/pdf en text Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-05-01 The student, Raihan Rahman, accepted the attached license on 2025-04-10 at 12:52. The student, Raihan Rahman, submitted this Thesis for approval on 2025-04-10 at 13:07. This Thesis was approved for publication on 2025-04-18 at 16:36. DSpace SAF Submission Ingestion Package generated from Vireo submission #21741 on 2025-10-19 at 19:14:38 Analyzing lexical features to predict Indian ITAs’ performance in a university oral English assessment Rahman, Raihan 2025-04-18 Yan, Xun Zhang, Qiusi Oral English assessment Lexical features lexical diversity lexical sophistication collocational use Indian ITAs language proficiency TESL eng This study investigates the extent to which lexical features can predict human rater assessments of high-performing Indian International Teaching Assistants (ITAs), examining whether metrics of lexical diversity, sophistication, and collocational use predict between Level 4 and Level 5 ratings. To address this question, sixty-six speaking test transcripts from Indian ITAs were analyzed using computational tools that generate quantitative measures of vocabulary use, including TAALES and TAALED. Binary logistic regression analysis revealed that while lexical diversity measures did not significantly predict between advanced proficiency levels, lexical sophistication measures (word frequency) and collocational metrics demonstrated moderate predictive power. The findings show a complex pattern where Level 5 candidates tend to use less frequent individual words but more conventional multi-word expressions, suggesting sophisticated vocabulary deployment that balances precision with accessibility. These results contribute to both the theoretical understanding of lexical development at advanced proficiency levels and the practical assessment of ITAs, suggesting that beyond a certain threshold, lexical sophistication and collocational competence play more decisive roles than diversity in predicting highly proficient speakers. 2025-05 Thesis https://hdl.handle.net/2142/129522 Copyright 2025 Raihan Rahman Linguistics Teaching of English Sec Lang University of Illinois Urbana-Champaign M.A. Thesis