This is a video recording from when I gave the math department colloquium on January 18, 2013.  It’s about the optimal stopping problem I’m working on with Al Cohen of Michigan State.  This was in a room where the whiteboard is actually special paint, directly on the wall.  The first part of my lecture goes well enough until the pens start running out and I start having trouble erasing.  These are all dry erase markers, but the surface of the board is very rough, so ink gets trapped in the pitting, and the erasers just can’t get it out.  Basically, the prep job before the paint was applied was not very good.  Rumor also has it that the housekeeping staff cleaned these walls with something they shouldn’t, which ruined the finish on the paint and made it that much worse.

So part way through, I switched over to using my Android tablet, which leads to other problems: The wide-screen projection is not nearly as big as the whiteboard (which actually goes all the way around the room, though I tried to use only the part visible to the camera).  Writing with a stylus on a tablet is also surprisingly difficult, and I actually did do some practicing, but still a lot of what I write on the tablet is very hard to read.

In short, after this experience I’m even more unhappy that The Plan was (and possibly still is) to redo all the classrooms to be like this one, while encouraging faculty to switch as much as possible away from blackboards, over to whiteboards, smartboards, document scanners, and tablets.  But if it doesn’t erase or the image size is too small, well, it just won’t work for us math folks.

Concerning the mathematical content: In this presentation, I give a brief introduction to stochastic calculus and sketch how you solve optimal stopping problems.  It would take me at least two more hours to explain the partial solution we’ve got for this Brownian bridge problem we’re working on.

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