Talking of Teaching

The University of Nottingham has a blog called Talking of Teaching at

They have just posted links to the recordings of the seminars three of us gave on March 4th at a Teaching and Learning seminar.

Mine is available at

Three points to note:

  • I had my webcam at a slightly awkward angle, and it was set to “follow my face” (software, not mechanical), which means that the viewer can get a bit seasick if I move around too much.
  • As mentioned in an earlier post, I failed to turn the mains power on at the socket. This has affected the audio quality in my recording. This was ironic, because one of the points I mentioned was how important it was to make sure that your laptop is on mains power if you are using software on the laptop to record audio/video. (In this case I was using Echo360 Personal Capture on my laptop.)
  • The small blue square visible in my recording was not visible on my laptop  screen. Echo360 Personal Capture apparently doesn’t always capture exactly what you see on your screen. (We have raised this as an issue with Echo360.) Subjectively, I have found that Camtasia is more reliable from the point of view of recording what you actually have showing on your screen, but that Echo360 appears to maintain synchronization better between the various recorded streams. Some sub-comments here:
    – I have no “small square” problems when using the resident Echo360 systems (which, I think, actually record what is being sent to the data projector).
    – Things have improved! A few years ago, Echo360 Personal Capture could not record my “digital pointer” (CursorAttention) properly: where I saw a clear red highlighter on my screen, the recording showed a generic mouse pointer instead.) We raised this as an issue then, and it looks like it has been fixed.

May Fest 2015

Finally it’s spring (in some sense), and that means that May is not too far away. And that means we have May Fest to look forward to!

The University of Nottingham’s Open Day for the community

Saturday 9 May 2015


Below are links to the flyer and the full programme for the day. Maths is on page 14 of the programme (“Othello at the Casino” this year. Last year it was “Why did the chicken cross the Moebius band?”)

May Fest 2015 Flyer

May Fest 2015 Programme

Mathematics as an oak tree

The University of Nottingham’s Ivan Fesenko was interviewed today on the radio about the project (a Nottingham/Oxford collaboration) to attack two famous open problems (the Riemann Hypothesis and the Birch and Swinnerton-Dyer Conjecture).

I’m not sure whether you can play this audio outside the UK (or how long it will be available for) but it is currently at

starting at time 1:22:30

Change in YouTube auto-generated lists

I see that there have been changes to the YouTube auto-generated lists.

The previous auto-generated #PureMathematics list has vanished, and been replaced by a new one at

which appears to be completely different from before.

Associated with this is a new Pure Mathematics playlist at

(The top three are Raymond Flood, but most of the rest are mine!)

I have no idea how the order is decided!

It works better if you switch it on

Yesterday afternoon I gave a talk about Lecture Capture. I was in a room where I needed to run recording software on my own laptop, and I was a bit out of practice, so in the morning I recorded a lecture using the same method. That worked OK! So I was fairly confident that I would get a decent recording in the afternoon.

One of the points I mentioned repeatedly in the talk was the importance of making sure that your laptop is plugged in to mains power when you are using several pieces of resource-hungry software at the same time. So it was ironic that I had failed to flick the power switch at the socket, and my laptop was running on battery power throughout the session. As a result, my own recording has a number of the usual issues, including poor sound quality.

Perhaps I should still publish the recording, since, as well as having some useful guidance in it, it also serves as an illustration of what can happen if you fail to follow the guidance!

Injections vs bijections: University Challenge error

My colleague David Hodge just showed me an extract from a recent University Challenge where they were asked the following question.

“Which type of function associates at most one element of the domain with each and every element of the codomain?”

The students weren’t sure, but (in my opinion!) correctly answered “Injection”. However they were told that they were wrong, and that the correct answer was “Bijection”.

Maybe we should write in and complain?


Confusion involving less than or equal

Every year a number of my first-year students are confused by the “less than or equals” relation.

Some students are confused when I claim that 2 \leq 3 or when I claim that 1 \leq 1 (or both).

You can see what happened this year when I mentioned that 2 \leq 3:

As I said, I get questions about this every year.

I think that the confusion goes via a subtle conversion of “or” to “and”, as in  “it might be less than and it might be equal”, and this jars when they see examples where it is blatantly one and not the other.

Some students like diagrams a lot, and so number line sketches could help illustrate the concept more clearly.