任务复杂度对二语写作产出影响的元分析 = The effects of task complexity on L2 written production: A meta-analysis

The effects of task complexity on L2 written production have consistently garnered research attention in the field of SLA. Over the past decade, researchers at home and abroad have conducted a series of meta-analyses on the topic. However, these meta-analyses mostly focus on a specific context without including recent publications, thus failing to offer a comprehensive view of the research domain. This meta-analytic study retrieved 51 Chinese and English journal articles involving 4632 participants and extracted 269 effect sizes from 88 independent samples to examine the effects of task complexity on L2 learners’ linguistic performance in written production. Results showed that: (1) Task complexity has small positive effects on syntactic complexity and lexical complexity and negative effects on accuracy and fluency; (2) increasing task complexity along the resource-directing dimension has positive effects on complexity and fluency but negative effects on accuracy, while decreasing task complexity along the resource-dispersing dimension improves complexity, accuracy and fluency, lending support to the Trade-off Hypothesis and Cognition Hypothesis; and (3) learners’ L2 type and L2 proficiency are the significant moderators for the effects of task complexity on L2 written production.