http://en.wikipedia.org/wiki/PID_controller
http://forumserver.twoplustwo.com/15/poker-theory/mathematics-poker-chapter-14-2-maximazing-bet-sizing-calculation-1429179/
http://www.youtube.com/watch?v=ObPg3ki9GOI
Since you know Calculus, you recognize all the prerequisite “basic Math” mentioned in video #2. Full playlist here.
http://www.youtube.com/watch?v=8ZLC0egL6pc