*Originally Posted 01-19-2012*

Today was a very long day at work. Long, but mostly enjoyable. There is still more to do, so I’ll keep this post short.

I began by taking a job candidate out for breakfast. This was very enjoyable. The candidate is a specialist in mathematics education, and we had a good discussion. I am not on the hiring committee, so it was easy (for me) to just talk and not have every word *carry weight*. It was interesting that most of the breakfast was pretty genial and smiley, but the candidate’s face really fell at one point when I said I disagreed with something. I had forgotten that this was an interview for the other half of the conversation… Upon reflection, I wish I had instead asked, “really? What makes you say so?” Somehow I have Mike Wolf’s voice in my head saying that. He was always good at disagreeing with me while being direct but friendly. Anyway, I enjoyed breakfast. Oh, and today was a terrible day to be wearing interview clothes. It is absolutely frigid.

After breakfast I took a little time to poke around with Apple’s new iBooks Author package. It doesn’t look very friendly for making technical documents at this point: the editor is WYSIWYG and there is insufficient mathematics support. And they are apparently just replacing the publishing industry instead of reinventing it. Somehow, you are allowed to make a book (for free), but the EULA demands that you only sell it through the iBooks Store. So that is three strikes already. Nothing revolutionary, just a shiny anodized aluminum case for the old publishing paradigm.

I had meetings with two students about research today. The first is making slow progress. I suspect that he is not spending that much time on the problem right now, and I’m trying to make up my mind on when to say something about it. The second is only getting started, so we had a brief but productive conversation and he was off to work again.

In between I negotiated a letter of recommendation request. Rather, I presented my demands. If they are met, I’ll write the letter. I think that brings the current pile to four waiting to get done–so I’ll have to save some time in the afternoon next week to get those written and sent.

After my meetings, I had a blissful few hours to myself. So I read a bit in the notices I got and the January issue of the Monthly over a mug of tea. Then I worked out some new problems for my Math in Decision Making class. If you’d like to see them, they are here. Basically, I think the class has come around to the fact that two sets have the same size if there is a ‘matching’ between them, so the next collection of problems is meant to sharpen that idea and push on the weirdness of this notion for infinite sets. I have enough material to last at least four more classes, likely six. I think somewhere in here they will have to slow down. I am just not sure which problem is going to be the stickiest. By the way, it bears repeating that this sequence is adapted from one written by Doug Shaw, though responsibility for the awful condition of the current set of tasks is all mine.

I haven’t updated my dynamics sequence, yet, because I haven’t needed to. I suspect that the students will force me to change that this weekend. They are doing a pretty good job at keeping up with the pace I have set. I think the next example they need is the doubling map. It will serve as a good gateway to all sorts of things for the rest of the term.

The last event for the day was a Math Club meeting, which was very enjoyable. There was no real agenda for today, and the students just played games. One of my colleagues brought her ten-year-old daughter who demolished me (and three students) in a game of Set. A small group of students tried out a game called Sleuth, which is a bit like Clue and looks like a lot of fun. One of my students said something about my cheating at the game so I could home and blog about it. If he is reading this one, he knows I have to fail him now.

I’m off to prepare materials for linear algebra tomorrow. I think our activity will involve reverse engineering some systems of equations to satisfy certain conditions. If the students use what we discussed about reduced row echelon form (or about the geometry of the dot product), they will go far. Perhaps I’ll turn it into a game. Pairs of students will create (and then disguise) systems which have a certain set of conditions, and then we will trade and see if we can remove the disguises. I also intend to quickly introduce the terms *rank* and *determinant* for matrices. It is about time I got off the stage in that class.

Good night internet. Sleep tight.