Korean EFL Learners’ Noun Phrase Errors in Academic Writing Across Writing Proficiency Levels : A Perspective from Noun Phrase Complexity = Korean EFL Learners’ Noun Phrase Errors in Academic Writing Across Writing Proficiency Levels: A Perspective from Noun Phrase Complexity

다국어 초록 (Multilingual Abstract)

Korean EFL Learners’ Noun Phrase Errors in Academic Writing Across Writing Proficiency Levels: A Perspective from Noun Phrase Complexity Shin, Seung Won Major in English Education Graduate School of Korea National University of Education Chungcheongbuk-do, Korea Supervised by Professor Kim, Minkyung, Ph.D. The present study investigated the relationship between noun phrase (NP) error types, NP complexity stages, and writing proficiency among Korean high school EFL learners. Specifically, this study aimed to examine (1) how NP error types differ across proficiency levels and (2) how NP error distributions vary across both proficiency levels and NP complexity stages in learners’ argumentative writing. While previous studies have extensively examined NP complexity as an indicator of L2 writing development using standardized proficiency measures such as TOEFL or IELTS (e.g., Biber et al., 2011; Parkinson & Musgrave, 2014; Lan et al., 2019; Nguyen, 2024), relatively little attention has been paid to NP error distributions in classroom-based secondary EFL contexts. The participants were 101 Korean high school EFL learners enrolled in English Reading and Writing classes at a public academic-track high school. All students completed an in-class timed argumentative writing task, producing a corpus of 101 essays. Writing proficiency was assessed using an adapted version of the ESL Composition Profile (Jacobs et al., 1981), and learners were classified into three groups: Higher Proficiency (HP), Medium Proficiency (MP), and Lower Proficiency (LP). NP error types were identified based on Kang et al.’s (2015) taxonomy, and both raw and normalized frequencies (per 100 words) were calculated. NP complexity stages were classified using the developmental index proposed by Biber et al. (2011) and Parkinson and Musgrave (2014). To examine the association between NP error types, proficiency levels, and NP stages, chi-square tests were conducted. For statistical stability, NP error types were collapsed into lexical and grammatical/structural categories, and Stages 4 and 5 were combined when necessary. The results showed that although the overall frequency of NP errors decreased with increasing proficiency, the proportional distribution of NP error types did not differ significantly across proficiency groups. Across all groups, NAE (Noun Agreement Error), NCE (Noun Word Choice Error), and NDE (Noun Determiner Error) were the most frequent error types. Stage 3 accounted for the highest proportion of NP errors, and a statistically significant association between proficiency level and NP error category emerged only at this stage. Lower-proficiency learners produced disproportionately more lexical NP errors, whereas higher-proficiency learners produced relatively more grammatical NP errors.
Key Words: noun phrase (NP) errors, NP complexity stages, L2 argumentative essays, grammatical and lexical accuracy, EFL classroom

목차 (Table of Contents)

• CHAPTER 1 INTRODUCTION 1
• CHAPTER 2 LITERATURE REVIEW 3
• 2.1 Characteristics of Constituent Components in Academic Writing 3
• 2.2 A Developmental Sequence for NP Complexity in Academic Writing 5
• 2.3 Types of NP Errors among Students 11
• CHAPTER 3 METHODOLOGY 16
• 3.1 Participants 16
• 3.2 The Datasets 17
• 3.3 Analysis of NP Complexity Stages and Error Types 22
• 3.4 Data Analysis 24
• CHAPTER 4 RESULTS 26
• 4.1 Types of NP Errors across Writing Proficiency Levels 26
• 4.2 Erroneous NPs across Complexity Stages 35
• 4.2.1 Erroneous NPs on Complexity Stage 1 37
• 4.2.2 Erroneous NPs on Complexity Stage 2 41
• 4.2.3 Erroneous NPs on Complexity Stage 3 46
• 4.2.4 Erroneous NPs on Complexity Stage 4 53
• 4.2.5 Erroneous NPs on Complexity Stage 5 56
• 4.3 The Complexity of Erroneous NPs Across Writing Proficiency Levels 59
• CHAPTER 5 DISCUSSION 62
• 5.1 NP Error Types Distributions across the Writing Proficiency Levels 62
• 5.2 The Distributions of NP Error Types Across Writing Proficiency Levels and
• Complexity Stages 66
• 5.2.1 NP Error Types on Stage 1 66
• 5.2.2 NP Error Types on Stage 2 67
• 5.2.3 NP Error Types on Stage 3 68
• 5.2.4 NP Error Types on Stage 4 and Stage 5 71
• CHAPTER 6 CONCLUSION 73
• REFERENCES 77
• 국 문 요 약 81
• APPENDICES 83