“…Specifically, we analyzed how researchers operationalized and measured the outcome variables they were predicting in their various models. Our analysis suggests that learning outcomes have been defined as course completion (e.g., Crossley et al, 2015; Loya, Gopal, Shukla, Jermann, & Tormey, 2015), engagement (Sharma, Jermann, & Dillenbourg, 2015), social interactions (Vu, Pattison, & Robins, 2015), sociability (Brooks, Stalburg, Dillahunt, & Robert, 2015), and learning gains (Koedinger, Kim, Jia, McLaughlin, & Bier, 2015; X. Wang, Yang, Wen, Koedinger, & Rosé, 2015).…”