This study reports on a meta-analysis on the effectiveness of corrective feedback in second language acquisition. By establishing a different set of inclusion/exclusion criteria than previous meta-analyses and performing a series of methodological moves, it is intended to be an update and complement to previous meta-analyses. Altogether 33 primary studies were retrieved, including 22 published studies and 11 Ph.D. dissertations. These studies were coded for 17 substantive and methodological features, 14 of which were identified as independent and moderator variables. It was found that (a) there was a medium overall effect for corrective feedback and the effect was maintained over time, (b) the effect of implicit feedback was better maintained than that of explicit feedback, (c) published studies did not show larger effects than dissertations, (d) lab-based studies showed a larger effect than classroom-based studies, (e) shorter treatments generated a larger effect size than longer treatments, and (f) studies conducted in foreign language contexts produced larger effect sizes than those in second language contexts. Possible explanations for the results were sought through data cross-tabulation and with reference to the theoretical constructs of SLA.

A meta-analysis was conducted to examine the construct validity of language aptitude by synthesizing the existing research that has been accumulated over the past five decades. The study aimed to provide a thorough understanding of the construct by aggregating the data reported in the primary research on its correlations with other individual difference variables and with second language (L2) achievement. A total of 66 studies were retrieved that contributed effect sizes based on 109 unique samples and 13,035 foreign language learners. The results revealed that (1) aptitude was independent of other cognitive and affective factors: it was distinct from motivation, had a negative correlation with anxiety, and overlapped with, but was distinguishable from, intelligence; (2) executive working memory was more strongly associated with aptitude and aptitude components than phonological short-term memory; (3) aptitude measured using full-length tests was a strong predictor of general L2 proficiency, but it had low predictive validity for vocabulary learning and L2 writing; and (4) different aptitude components demonstrated differential predictive validity for different aspects of learning. The findings are useful for tackling a number of conundrums surrounding language aptitude and shed light on how to reconceptualize the construct and reorient the research.

Learner beliefs are an important individual difference in second language (L2) learning. Furthermore, an ongoing debate surrounds the role of grammar instruction and error correction in the L2 classroom. Therefore, this study investigated the beliefs of L2 learners regarding the controversial role of grammar instruction and error correction. A total of 754 L2 students at an American university completed a questionnaire consisting of 37 Likert-scale items and 4 openended prompts. The quantitative items were submitted to a factor analysis, which identified 6 underlying factors (efficacy of grammar, negative attitude toward error correction, priority of communication, importance of grammar, importance of grammatical accuracy, and negative attitude toward grammar instruction). These factors were then used to investigate differences in beliefs among learners studying different target languages. In addition, themes emerging from the qualitative data were identified. The results indicate that among learners studying English as a second language and those studying a foreign language, there were varied beliefs about grammar instruction and error correction.LEARNER BELIEFS HAVE BEEN IDENTIFIED as an important individual difference variable in second language (L2) learning (Dörnyei, 2005;Kalaja & Barcelos, 2003). The importance of learner beliefs lies in the fact that they underlie learner behavior to a large extent (Horwitz, 1988). Grotjahn (1991) argues that learner beliefs are "highly individual, relatively stable, and relatively enduring" (p. 189) and that studying learner beliefs might help explain and predict behaviors

This study investigated the interactions between two types of feedback (implicit vs. explicit) and two aptitude components (language analytic ability and working memory) in second language Chinese learning. Seventy‐eight L2 Chinese learners from two large U.S. universities were assigned to three dyadic NS–NNS interaction conditions and received implicit (recasts), explicit (metalinguistic correction), or no feedback (control) in response to their non‐target‐like oral production of Chinese classifiers. The treatment effects were measured by a grammaticality judgment test and an elicited imitation test. The Words in Sentences subtest of the MLAT was used to measure language analytic ability; a listening span test was utilized as the measure of working memory. A principal components analysis and a structural equation modeling analysis established that working memory was an aptitude component. Multiple regression analyses showed that language analytic ability was predictive of the effects of implicit feedback, and working memory mediated the effects of explicit feedback; all the statistically significant results involved delayed posttest scores. Interpretations were sought with recourse to the mechanisms of the cognitive constructs and the processing demands imposed by the different learning conditions.

This study reports a meta-analysis that synthesizes the empirical research on the role of language aptitude in second language grammar acquisition. A total of 33 study reports were identified including 17 predictive studies that investigated the correlations between aptitude and ultimate L2 attainment and 16 interactional studies that examined the interface between aptitude and the effectiveness of instructional treatments. These studies generated 309 effect sizes and involved 3,106 L2 learners. It was found that aptitude showed an overall moderate association with L2 grammar learning, r = .31, 95% CI = .25-.36. Subsequent moderator analysis demonstrated that high school students were more likely to draw on aptitude than university students and that aptitude was more strongly correlated with explicit treatments than implicit treatments. The role of aptitude was more evident for younger learners than older learners in predictive studies whereas the opposite was true in interactional studies. The results suggest that language aptitude as measured via traditional aptitude tests is a set of cognitive abilities that were more implicated in initial stages of L2 development and conscious learning conditions. The findings are valuable to resolving some long-standing controversies surrounding language aptitude.