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Posts about bunnies (old posts, page 20)

The grass is greener

I was walking back home at 10am a few days ago, happily exhausted, and I happened to notice a sloped lawn of some houses next to my residence. That grass was really green! I then started looking around at other grass -- the corner of a wooded area, stuff growing in cracks on the pavement -- and yep, it was all really green. Much greener than the grass in Vancouver!

Granted, the last time I was in Vancouver it was late summer; not precisely a time noted for having lots of rain. And come to think of it, I can remember looking out the kitchen window last year and being surprised at how green the lawn looked. (especially my parent's back-yard lawn)

But hey, it made a nice introduction to this blog post.


My teaching ended almost two weeks ago, and I immediately shifted into my "sleep whenever I want" schedule. This normally results in a 26-hour sleep cycle (awake 17 hours, sleep 9 hours), but for the first time ever, I ended up on a 14-hour cycle. Awake 9 hours, sleep 5!

I felt great, though. And it was useful to have the shorter cycle, because it meant that I spent some time at university by myself (so I could get work done), but also some time there when other people were around (so they could test what I was working on).

Oh, as for "what I was working on"... half the lab is now in either Australia or New Zealand, for a series of conferences and/or workshops. I was preparing an electronic clarinet that plays in 19-tone equal temperament and unearthing a two-year old version of rosegarden with a 19-tone equal temperament pitch tracker. I was happy to volunteer for the task, but I underestimated the amount of work required.

I'm now porting the ancient rosegarden pitchtracker code to the latest version (using Qt4 instead of Qt3). I'm happy to report that so far, it's going exactly on schedule: this job should take a week.


Granted, that's another week that I'm not doing research. Speaking of research, I'm seriously reconsidering whether to include a metronome in the rhythm game. About half the people I've showed the game to (and everybody over here) have complained about the metronome. Or rather, they've complained about having to follow the metronome. (yes, I'm sure there's a pianist or singer or whatever joke in there somewhere)

But there is a serious issue there. I did a few quick tests on myself -- I had the computer give me a 4-beat metronome introduction (set to a random number between 60 and 120 BPM), I tapped the rhythm, then the computer told me my tempo. I generally varied between -5 BPM and +10 BPM. Now, I'm a great ensemble player. I'm not claiming on being the best musician ever, but when it comes to rhythms, aligning rhythms, keeping track of what everybody's playing, etc., I'm above average for a classical musician with 20 years of training. So if I naturally vary the tempo by that much, there's no point penalizing students for doing the same!

Basically, "with metronome" tests your ability to play rhythms in a large ensemble (say, an orchestra). But when you're playing chamber music or in a private lesson, the tempo is much more flexible. I'd estimate that in a normal "simon says" type of private lesson (teacher claps a rhythm, then the student claps it back), the teacher wouldn't complain if the student was +- 20% of her initial tempo -- and probably wouldn't even notice if it was +- 10%. (yes, I should spend more time looking at psychology papers to find exact numbers for these)

So I'm now thinking that the most useful rhythm training tool would give an initial "target" tempo, but then stop the metronome and let people clap or tap the rhythm. Technically, this means that I need to detect the tempo of the student's exercise. This is a well-known problem in Music Information Retrieval, but this application has special constraints. First, it needs to be very reliable; we don't want to give students bad grades because the tempo-detection algorithm gives the wrong answer. Second, it needs to be robust against incorrect rhythms. If somebody taps four 8th notes instead of four 16th notes, the tempo detection should still work.


All in all, it's looking like the actual rhythm survey won't happen until January. This week is devoted to cleaning up the mess of previous research in the group (i.e. the rosegarden thing); next week I'll start the tempo detection in earnest.

Happiness is...

Happiness is sitting in your university lab at 3:30am on Saturday morning, with a cup of lukewarm tea made with two-day old milk that's been sitting on a ledge outside the window because the fridge isn't working, eating nothing but Mars bars for the past four hours because nothing is open in the city, with half the lights turned off because they flicker unbearably, finally alone after all the labmates had left, and having implemented the Friedman test in python to check your experimental data.

Actually, I'm not totally alone. There's still the Chinese postgrad in the next lab. But that's far enough away that I consider myself alone.

I'm happy.


The experimental data is looking quite good -- the planned "best case" resulted in a p value of 0.00025. For those of you who remember as much about statistics as I did three hours ago, this means "it's really really really unlikely that the difference is due to random chance". Which translates into "you're doing the right thing".

Another set of exercises resulted in a low p value but unexpected results, which is exciting. The last two sets of exercises produced unclear results... but that's the whole point of a preliminary survey. As far as preliminary surveys go, I couldn't ask for anything better!


Residence heat: since the last report, we've lost heat twice and had it repaired twice. We've had heat for the last 8 days, which is the longest we've ever had it. Hopefully it'll last this time!

Speaking of heat, it's been disappointly warm outside. Ok, by "warm", I mean "5-10C", which doesn't strike most people as warm... but I was hoping for snow. Talking to my labmates, it doesn't sound like Glasgow gets much snow. :(

Glasgow seems to have the same Fall weather as Vancouver, which makes me quite at ease. Overcast, mixed rain and drizzle... that's the right kind of weather! I think it's a bit windier here than in Vancouver, although I might be mistaken since my bike path in Victoria didn't expose me to much wind. The rain here is no problem at all, but the drainage is quite poor: the sidewalk gains a few huge puddles -- at times, I walk along the road to avoid the sidewalk-puddles! At other times, I scrunch up against the fence away from the road, since the road has huge puddles which turn into fountains when cars drive through them.


On one such stormy and dark night, filled with chest-high puddle-car-splooshes, I trotted off to the university chapel to turn pages for a clarinet trio. For the non-classical musicians out there, this means "clarinet, cello, and piano". I did a good job on my first page-turning experience... I had to hold the page a few times as the fans threatened to turn the page at the wrong time, and the pianist thanked me for that extra duty.


I've finished demonstrating for the first-year analog+digital electronics class; the last two weeks were making a radio and making some "christmas lights" (just a series of LEDs flashing in a particular order). Next term, I'm teaching the first-year "introduction to C programming" course with my supervisor. I'm really looking forward to this -- especially since everybody (labmates, other postgrads, even faculty!) warns me about how terrible it will be. Bah! I'm not afraid of pointers, and I'm definitely not afraid of explaining them.

Next week, half the lab is going off to New Zealand (and maybe Australia?) for 2 or 3 conferences. With that, as well as the undergraduate teaching being over, I expect things to get much quieter. I should really be able to catch up on my research! Oh, by the way, I went off to a two-day workshop at the Open University at Milton Keynes a few weeks ago. Not really much to say about that trip, other than I met three people (one student, two professors) who were interested in my work and who were doing related stuff.


So, in the near future, I'll have much more time (and energy) for work. I'm getting involved in the 19-tone equal temperament pitch tracker for Rosegarden (we'll do the normal 12-tone as well, since most people would much rather have that). As previously mentioned, my preliminary survey of grading rhythmic exercises is done, so in the very near future I can launch the real survey. And I've already started thinking about the sheet music analysis + rhythm extraction + automatic exercise generation project.

My sleep schedule has been quite poor, so I've decided to go back to my 26-hour cycle. That's a major contribution towards my happiness... not having to worry about going to bed or waking up is a huge relief. I need to do some teaching on Monday and Tuesday next week (filling in for one of the people going to New Zealand), but after that my schedule will be blissfully free for self-scheduled work.

Am I hot or not? ... not.

You may recall me being very happy that our heater was fixed on 14 Oct. Well, less than a week later, it broke again. You may recall me being very happy that our heater was fixed on 2 Nov. Well, less than a week later, it broke again.

I'll give them 2 days to fix it, and then I'm writing a formal letter to the head of accommodation to remind them that their legal "residence contract" specifies that it is the university's obligation as a landlord to "ensure that there is kept in good repair and proper working order any installations provided by the University for space heating" and "provide gas and electricity". I haven't had any problems with electricity, but the latter is just there in case they try to argue that the heater is just fine; the problem was in the gas intake to the heater.


Other than that, things are fine. I was at the lab on Sat until 11pm, and on Sunday until 9pm. It's really feeling like home! I'm doing a pilot survey of rhythm grading, and it's really exciting watching the answers trickle in. I had 5 responses within an hour of the initial request, and 9 at the end of the first 20 hours.

Once the pilot survey is done, I'll make a better one (more specific questions, informed by the results of the pilot survey) and ask for help here. I think it might be bad experimental practice to re-use pilot survey people in the real survey (I'll check with our psych person), so I'm not looking for more people to do the first survey.

For teaching, we're doing ripple counters this week. Should be fun! It took me an hour to get through the lab... I misread the lab sheet's "connect the output of each flip-flop to the clock of the next flip-flop" as "connection the output... to the input of the next flip-flop", and ended up adding a bunch of needless logic gates to make it count properly. When I finally checked the lab sheet again, because I couldn't believe it was this complicated without more explanation, I noticed my mistake and easily finished it off.


We're going to London next week. Ok, not actually London; I think it's Milton Keynes. If that's pronounced "milton keens". Apparently we fly down to London, then take a coach for an hour to this place. In my Canadian mind, anywhere reachable within an hour's drive of a place is that place. So we're going to London.

(hmm, I guess that means that Glasgow is Edinburgh. Umm. I think most people in both cities wouldn't like that!)

Yes, there were dark mutterings in the lab about the travel arrangements... apparently they were brough about because it needed to be booked during the summer, and one can't book train tickets more than 3 months in advance.

Anyway, it should be a fun little jaunt. Or a little jaunt, at least. Apparently the place we're going to has "concrete cows", which sound like they're either highly awesome or highly non-awesome.

Kind-of like being hot or not!