Writing and studying for an exam is a game played between Professor and student.  In this game the Professor has to pick which questions to ask and the student has to pick which topics to study.  The game has the flavor of rock-scissors-paper in that the Professor would like to be unpredictable.  That way the students will have to devote studying time to all topics rather than focus on just one that they know the Professor will ask about.

But the Professor might not want the students to spend too much time memorizing concepts from the book.  Instead he may want them to spend their time thinking about how to apply those concepts to new problems.  How can the Professor be unpredictable and still deter the students from trying to memorize the book?  The solution is to use an open book exam.  This way the Professor is committing not to…