Linguistic features that are indicative of higher writing proficiency levels can inform many aspects of lanauage assesment such as scoring rubrics, test items, and automated essay scoring(AES). The recent advancement of computer algorithms that automatically calculate indicates based on various linguistic features has made it possible to examine the relationship between linguistic features and writing proficiency on a larger scale. While the ability to use appropriate n-grams - recurring sequences of contiguous words - has been identified as a characteristic differentiating between proficiency levels in the literature, few studies have examined this relationship using computational indices. To this end, this study utilized the Tool for the Automatic Analysis of Lexical Sophistication(TAALES;Kyle&Crossley, 2015) to calcualte eight indices based on n-grams from a stratified corpus consisting of 360 argumentative essays written by Korean college-level learners. First, the indices from the training set of 240 essays were used to design a multinomial logistic regression model in order to identify indices that are significant predictors of writing proficiency levels. Subsequently, the regression model was applied to a test set of 120 essays to examine whether the model could be used to predict the proficiency levels of unseen essays. The results revealed that the mean bigram T, mean bigram Delta P, mean bigram-to-unigram Delta P, and proportion of 30,000 most frequent trigrams indices were significant predictors of proficiency levels. Furthermore, the regression model based on eight indices correctly classfied 52.5% of essays in the test set, demonstrating above-chance level accuarcy.

The purpose of this paper is to investigate whether second language writings at different proficiency levels can be distinguished using automatic indices of linguistic complexity. For this study, 35 linguistic measures in 234 essays selected from the Yonsei English Learner Corpus were analyzed in order to identify the best indicators of L2 writing proficiency among the three categories: text length, lexical complexity, and syntactic complexity. The key to this study is the use of computational tools, the L2 Syntactic Complexity Analyzer and the Lexical Complexity Analyzer, which measure different linguistic features of the target language, and a robust statistical method, discriminant function analysis. Results showed that automatic computational tools indicated different uses of linguistic features across L2 writers’ proficiency levels. Specifically, more proficient writers produced longer texts, used more diverse vocabulary, and showed the ability to write more words per sentence and more complex nominalizations. These findings can offer a window to understanding the linguistic features that distinguish L2 writing proficiency levels and to the possibility of using the new computational tools for analyzing L2 learner corpus data.

This study investigates how EFL learner error patterns and frequencies differ in writing depending on students' language proficiency levels. A total of 152 Korean EFL students' essays were examined. The writing samples were first scored holistically on an impressionistic basis; then, based on the scores, the samples were grouped into low- and high-proficiency groups. The study identified 13 errors based on prevalence and significance. The study calculated the frequency of each error type committed by each group and compared the results using t-tests. A survey of English teachers was also conducted (N=32) to rate the gravity of each error and to compare the error gravity produced by each group. The result showed that low-proficiency group produced errors much more frequently, and the errors were more serious ones with high error gravity. The errors committed by the high-proficiency group were usually complex ones and occurred in more complicated contexts. The study also found that the errors with less gravity occurred more frequently in both groups and that they tended to be more persistent. The study indicated that although the students were aware of significance of errors, correcting the errors was beyond their current English capability.

The present study was designed to investigate Korean EFL college learners' language development across writing proficiency levels in the ir written productions. For the evaluation of their language development, 18 subsets of the syntactic complexity, accuracy, and fluency (CAF) were used. 86 uni vers ity students participated in the study and wrote narrat ive essays about an assigned topic by using the Criterion®. The writing samples were scored by e-rater® and divided into three different proficiency levels to compare language development among groups. Then their essays were analyzed by us ing L2 Sy ntactical Complexity Analyzel: The findings reveal significant differences in 15 out of 18 measures of CAF and language learners' linguistic developmental patterns across their writing proficiency levels. The results indicate that there are di stinctive features regarding CAF among the three groups. With respect to fluency and accuracy, levels I and 2 showed a similar language developmental pattern, and level 3 was much higher than those groups. In terms of syntactic compl exity, levels 2 and 3 presented a similar developmental pattern, and level 1 was much lower than those groups in general. This study shows the predictive potential of CAF across writing proticiency levels of language learners.

The study investigated whether Korean EFL students' vocabulary used in reading-based writing differed according to writing topic and their reading and writing proficiency. College students enrolled in writing courses (n=95) were asked to write argumentative essays in response to two readings on judging people by appearance (JPA) and disclosing personal information of serious criminals (DPI). These students were divided into high and low proficiency writer groups and into high and low proficiency reader groups according to their writing and reading scores respectively. The students' vocabulary used in writing was then analyzed by VocabProfile, which provided four lexical frequency lists: the first 1000 frequent words (K1) including function words (FW) and content words (CW), the second 1000 frequent words (K2), academic word list (AWL), and off the list words (OLW). The results indicated that the topic JPA produced a higher proportion of K1 and content words, whereas DPI generated more K2 and off the list words. None of the vocabulary profiles, however, significantly differed according to the students’ reading proficiency. In contrast, proficient writers were found to use significantly more K1 and function words than their counterparts. With the topic effect further considered, for JPA, proficient writers used more K1 words and function words whereas less proficient writers used more K2 and off the list words. With regard to DPl, proficient writers were found to use more function words than low proficient writers. Findings are discussed in more detail, along with implications.

The majority of studies on L2 writing strategies to date has relied heavily on case study as a research methodology employing think-aloud protocols and texts written by the participants. Since the studies dealt with a small number of participants, the findings are inconclusive and sometimes contradictory, and little research on the writing strategies has been conducted in EFL contexts. The present study investigated EFL learners" writing strategies and compared the more-proficient writers" strategies to those of the less-proficient peers. It furthermore examined an assumption of a connection between writing strategy use and writing proficiency. The study was conducted with two writing classes that consisted of 26 more-proficient and 23 less-proficient writers. Two different proficiency groups were divided in proportion to students" scores on the diagnostic composition test. Strategies were measured by means of the modified questionnaire originally developed by Petri？ and Cz？rl (2003). The strategy items were stated in three different phases of the writing process (planning, while-writing, and revising). The results indicated that (1) the more-proficient writers used significantly more planning and while-writing strategies and (2) planning and revising strategies correlated significantly with students" composition scores.

The English to-infinitive structure has over a dozen different functions, presenting a difficult area for EFL students. The present study shows a relatively dynamic profile of the use of ten to-infinitives functions appearing in EFL children's story writing as the children progress in grade levels and English proficiency—an area that has never been investigated previously. To-infinitives that function as an ‘object’ or ‘purpose’ were most prominent. The students used a higher number of to-infinitives as they progressed from the third to sixth grades. The increase between the four adjacent grade levels did not reach a level of significance, but the increase between middle (third and fourth) and upper (fifth and sixth) levels was significant. The difference was striking when the entire group was re-sorted into lower vs. higher proficiency groups: the increase in the use of to-infinitives was better explained by English proficiency improvement than by grade level progression. This in-depth analysis into the sub-functions adds to the existing knowledge about to-infinitives, which might otherwise remain oversimplified.