Instructors often use their course data to research the effectiveness of assignments.
Here's are some of things instructors have published with the help of OK
Talk: How the OK Software Suite has helped CS 61A scale to 1600 students in a single semester.John DeNero, EECS Colloqium Invited Talk - October 19, 2016
Fuzz-testing projects discovered errors in 50% of students that instructor created tests missed.Sumukh Sridhara, Brian Hou, Jeffrey Lu, and John DeNero
A technique to identify conceptual misunderstandings from constructed response questions.Kristin Stephens-Marintez, An Ju, Colin Schoen, John DeNero, Armando Fox
Using program synthesis to create hints using past submissions from others.Rolim, R. et al. (2016)
Combining program synthesis and teacher feedback to give hints for incorrect programs.Andrew Head, Elena Glassman, Gustavo Soares, Ryo Suzuki, Lucas Figueredo, Loris D’Antonik, Bjorn Hartmann