One-on-one and small group conversations with an intelligent virtual science tutor. - Ronald A. Cole; Cindy Buchenroth-Martin; Timothy J. Weston; Liam Devine; Jeannine Myatt; Brandon Helding; Sameer Pradhan; Margaret McKeown; Samantha Messier; Jennifer Borum; Wayne H. Ward (Comput. Speech Lang., 2018)