Joshua Littenberg-Tobias, José A. Ruipérez Valiente, Justin Reich. Impact of Free-Certificate Coupons on Learner Behavior in Online Courses: Results from Two Case Studies. In Proceedings of the Sixth ACM Conference on Learning @ Scale, L@S 2019, Chicago, IL, USA, June 24-25, 2019. ACM, 2019. [doi]
Abstract is missing.