“…This is particularly prominent in L2 writing context, since students as second language learners may be at differing stages of L2 development and thus have differing abilities to provide accurate, informative and useful feedback on L2 writing (e.g., Nelson & Murphy, 1993;Yang et al, 2006;Zhang, 1995). Students generally regard their teacher as the only authority capable of giving feedback on their L2 writing (e.g., Sengupta, 1998), which may well explain why there has been abundant L2 writing research comparing the efficacy of teacher and peer feedback for students' draft revisions and writing quality improvements (e.g., Chaudron, 1984;Connor & Asenavage, 1994;Crookes, Davis, & Caulk, 1994;Jacobs & Zhang, 1989;Mei & Yuan, 2010;Paulus, 1999;Shih-hsien, 2011;Tsui & Ng, 2000;Zhao, 2010) or exploring the effects of training on improving peer feedback quality and usage (e.g., Berg, 1999aBerg, , 1999bHu, 2005;Liou & Peng, 2009;Min, 2005Min, , 2006Min, , 2008Rahimi, 2013;Rollinson, 2005;Stanley, 1992;Zhu, 1995). Moreover, except for a few exceptions (e.g., Berg, 1999a), most of the previous research on peer feedback in L2 writing examined a relatively homogeneous group of students in terms of language proficiency.…”