dangermouse.net – Page 92 – David Morgan-Mar

Kicking off machine learning

Monday… The final ethics class on the topic of fairness in sports. Tomorrow I write up the notes for the next week of classes. I’m up to doing 10 classes a week now! I also need to get working on that course outline for creative thinking and problem solving.

This evening I am tutoring the first lecture on machine learning for my image processing course. It’s quite introductory, with just an overview of machine learning, very light on the guts of how it works. The technical part is mostly all on probability distributions, which is the fundamental maths required to understand how machine learning works. It’s very different to courses that I’m used to. It doesn’t delve down far enough to understand how everything works in enough detail to implement it from scratch. Which I grant is appropriate for the audience, engineering and business students doing one course in image processing to get some idea how it works, rather than people destined for a career in image processing who need to understand it a very fundamental level.

New content today:

Everyone’s out walking, and Sunday ethics

It’s Sunday, and spring is definitely arriving in Sydney. New green shoots and leaves are sprouting on trees, and flowers are bursting out everywhere. The weather is warming up, though we’ve had a couple of chillier days just now, but later this week it’s going to be beautiful and warm.

We went for a longish walk with Scully today around lunchtime. There were so many people out walking around, it was notably unusual. Dozens of people hanging out in the park area where we toss balls for Scully to chase, when it’s been much emptier recently. I guess the warmer weather is starting to bring people out a bit more. Nearly everyone is wearing masks now, because of the COVID lockdown rules about wearing masks outdoors. (Speaking of which, 1218 new cases today – yet another record high for Australia.)

This evening I had my first ethics class on a Sunday. I’ve been resisting putting them on the weekend to keep some days free, but at the moment school is starting up in many countries and the parents are all eagerly asking me to move their kids to classes at other times and dates to accomodate. I had several requests for weekend classes, so I finally gave in, and today I had a full class of four kids in my very first Sunday class. I may end up putting another Sunday class on too.

New content today:

More experimental baking

I had more leftover sourdough starter today, so I decided to try making some sourdough focaccia using it, plus a bit of yeast to get it to rise. (Sourdough rises when the starter is fresh, but not if the starter has been left over and sitting for a few days.)

It turned out pretty well!

I think I baked it a little too long, and next time I won’t use the base heat setting in the oven, as it made the base very crisp and close to burnt. But otherwise it was really good. For dinner I made a simple tomato and chilli sauce with pasta, and we have that with the focaccia and some extra virgin olive oil and balsamic vinegar to dip it in. A very simple and rustic Italian meal, but delicious.

In other news, Scully had her groom today, and now she’s all fuzzy and velvety with short hair again. I didn’t get a photo to compare with yesterday, but maybe I will tomorrow.

I spent the afternoon working through the exercises for Monday’s next lecture in the image processing course I’m tutoring. We’ve finished the basic image processing stuff and are moving on to machine learning for pattern recognition. I have a very high level knowledge of machine learning, but have never dealt with the nitty gritty aspects of it in detail before, so this part of the course will be more challenging for me. This first lecture is really an introduction to machine learning, and most of the actual work is on probability distributions, which I have more familiarity with. So the work wasn’t too difficult, although I had to struggle with Matlab’s weird syntax issues for a while before getting something to work.

I’ve also started work on a new course for Outschool, to complement the ongoing classes on critical and ethical thinking. This new one will be a fixed length course of about 6 weeks, on creative thinking and problem solving. I plan to teach the kids how to think about problems and come up with creative solutions to them. And as an example context, I thought that over the six-week course we could work on a specific creative problem: designing a simple board game! The goal would be to have a completed, playable game at the end, invented by the kids, with my guidance. I think this should work well as a course, and I have ideas for all the stages. Just need to write it up and then submit the course for approval.

New content today:

Down at the wharf

Today was fairly routine. I picked up my grocery order form the supermarket, and again stopped to buy three punnets of super cheap strawberries, like last week. I made some comics. I did a couple of ethics classes.

At lunchtime I went for a walk with my wife and Scully, down to a nearby wharf.

She’s so photogenic.

She’s looking very shaggy at the moment, because it’s been a long time since her last groom. She’s booked in for another on tomorrow.

Tonight is the regular fortnightly games night with my friends. We have a special treat tonight, in that one of the guys has written a trivia quiz for the rest of us to play. We’re going to divide into three teams and fight it out for trivia supremacy.

New content today:

Some pleasing feedback

Bad news first: New South Wales recorded 1029 new COVID cases in the past 24 hours. This is the first time since the pandemic began that Australia has recorded over 1000 cases in one day. On the bright side, vaccinations are proceeding at extremely high rates – I think I heard that Australia’s per capita vaccination rate is currently higher than any other country in the world has had at their peak rates. Unfortunately we’re starting several months behind, but we’ll get there.

Now the good news:

I set myself a small goal today: make 3 new Darths & Droids strips. I’m happy to say that I managed to achieve it.

But the thing that really made my day was during my third online ethics lesson for the day. As we started the Zoom call, with myself and three students, one of the girls sent me a private message via the Zoom chat window. She asked if she could stay briefly after the class to ask me a question. I said yes. So after the class ended and I said bye to the two other students, she stayed on the call.

She said that she would be starting school next week after the summer holidays (she lives in Sri Lanka), and that she wouldn’t be able to attend my ethics class at the same time, because she’d be in school. She wanted to know if I had other classes at different times, so that she could continue. She said that she really, really enjoyed my classes, and that she looked forward to them every week, and didn’t want to have to miss out on them.

Wow. This was the best and most personal feedback I’ve received for this course, and it really made me feel good! I told her that I had several other timeslots, and it would be best if she and her parents looked through them on Outschool – and also that if she couldn’t find one that suited her schedule, to contact me through the Outschool messaging to see if I could add another class at a suitable time. I also said that if that didn’t work out, then she could rejoin the class during her next school holidays. And when I said that, her face lit up and she said, “Oh! I hadn’t thought of that! Yes, I’ll definitely do that!”

So, I’m feeling pretty chuffed tonight.

New content today:

Ethics of sport

It was still cold today, but a bit warmer and much less wet than yesterday. We ended up with just under 40 mm of rain, which is substantial for a single day. It didn’t rain at all today, but we may get some more showers later in the week.

I mainly worked on Darths & Droids today, until it was time to begin the new week of ethics classes. I’ve gone up to three classes on Wednesday evenings thanks to the demand, so I taught a total of ten students tonight. There was an interesting range of answers across several of the questions.

I started with the story of the adoption of long-handled putters by professional golfers in the 1980s, and how they helped golfers to putt more accurately. I asked questions about whether newly invented equipment should be allowed in sports, and most of the kids thought it was okay. Then I asked if everyone used the new gear, was it really the same sport? This was more polarising, as some kids said yes, while others thought that if the skills involved have changed, then it’s really a different thing. Then I asked if sports should evolve with new technologies, or if they should remain traditional, and most of them thought they retain the traditional form, but you could spawn off new sports using new gear.

Switching to the introduction of the full body swimsuits that competitive swimmers used from 2000-2008, I asked if it was fair for a swimmer (specifically Ian Thorpe at the 2000 Sydney Olympics) to use a newly invented swimsuit which none of the other swimmers had even seen before, and which helped his body slip through the water with less resistance. They mostly thought it was unfair, but not exactly cheating, as the rules at the time didn’t ban it. They thought it would be fair if all the swimmers could use the new suit.

Then I pointed out that the new suits actually made swimmers faster, as shown by the huge numbers of world records that were broken in those years. I asked if that was really fair, or should swimming by solely based on your muscles and skill? This got mixed responses, from kids who thought it was fine, to ones who thought you couldn’t really even call it swimming any more, if some technology was helping you swim faster. I asked them who should decide if such technology should be allowed, and what issues they should consider.

We moved into football, and Diego Maradona’s famous “Hand of God” goal in the 1986 World Cup. He handballed a goal, but the referee didn’t see it, and awarded the goal, and Argentina won the match. If the referee didn’t see it, was it cheating, or was it just a thing he did to try and win, and got away with it? Should professional athletes try to win at all costs? Should Maradona have admitted to the referee that he handballed, or should he have let the referee decide for himself?

Then I asked the kids to imagine they were playing tennis against a friend. There’s no umpire to spot foot faults, so they can creep forward and serve stronger without their friend noticing. If they knew they could get away with it, would they cheat to beat their friend? Most kids said no, but two of them said yes they probably would – because they would want to beat their friend to show off how good they were! That was interesting! I praised them for their honesty, in telling me, if not for their approach to sports. Then I asked them if they were professional athletes, would they cheat if they knew they could get away with it. This time a few more of them said they would – but interestingly one of the kids who said he’d cheat against his friend said he wouldn’t cheat if he was a pro – because it’d be on TV and everyone would know, and he’d get a bad reputation.

So… it was all very interesting! I have a follow-up topic planned for a few weeks later, on the topic of performance-enhancing drugs in sports.

New content today:

Winter storm incoming

Any story of today has to be about the weather. After yesterday’s 27°C winter heat, the cold front moved in overnight, bringing rain and cold. Today’s maximum temperature was recorded at 6:02 am, at just 11.4°C, making today the second coldest day of the year (10 June was just 10.3°C). It’s now 8 pm and Sydney has recorded 37 mm of rain in the city, up to just under 50 mm at the airport. The rain is expected to get heavier tonight, with accompanying gale force up to storm force winds. Wind gusts are already up to 70 km/h on Sydney Harbour. There are fears of beach erosion with the high seas that may threaten some coastal properties.

While this was unfolding today, I had a bunch of stuff to deal with. When we moved in here, there was an in-sink garbage disposal unit, for mulching food scraps into the drain system. I’d never lived with one before, but we started using it and got used to it. But last week it gave up the ghost, the motor seizing up. I called a plumber to see if we could just get it removed and replaced with a regular drainage pipe. No problem! And home repairs are one thing that is allowed to continue under our current COVID lockdown rules, so this morning the plumbers arrived to do the job. Rather than just replace the disposal unit, they redid all of the pipes leading from the double kitchen sink to the drainage port in the floor, replacing the semi-clogged trap and the old pipes that would threaten to start leaking a some point with brand new ones. The sink drain holes also have shiny new grilles in them. And there’s more space inside the cupboard under the sink where we store all the cleaning stuff and other things (watering can, toolbox, light bulbs, candles, matches, etc), so we used that to clear away some stuff off the kitchen bench. Overall a big win!

Then at lunch time I had to go pic up the car from some minor repairs. The repair place is about 20 minutes walk away. In the pouring rain and freezing cold. They had to pick the one day of the week when it was the absolute most miserable to be outside. Well, I took advantage of having to walk over there to stop in at a pie shop on the way for some lunch. As well as repairing the car they’d washed and detailed it nicely. Which didn’t last long…

Back home, I used the newly repaired car to take Scully to doggie daycare. And brave the rain again. In the afternoon I actually did some productive stuff, writing my class notes for this week’s new ethics topic: Fairness in Sport.

Then in the early evening I went to pick up Scully. When the rain and wind had intensified. When she goes to daycare, apparently she has so much fun playing with the other dogs that she completely forgets any need to pee or poo, with the result that as soon as I pick her up she has to rush to the nearest grass and relieve herself. With the rain coming horizontally and my umbrella threatening to turn inside out. And then once both of us were thoroughly wet we climbed inside the car to head home.

Here’s Scully on a sunnier day, last Saturday (bandana by Scully xo, my wife’s Etsy shop):

For dinner tonight I tried something new: sourdough pizza dough. I’ve been making pizza dough for a while now – it’s incredibly easy and I don’t know why I didn’t try it earlier. This time I tried adding some leftover sourdough starter to the mix to see how it works, and it turned out really good!

New content today:

Not so warm, expecting rain

Monday… it was supposed to be warm today, but it didn’t quite reach the heat forecast yesterday. It clouded over early, and has been threatening rain most of the day, but with very little actual rain. That should change later this evening and into tomorrow, because the forecast for tomorrow is 45-90 mm of rain! There’s also supposed to be some moderately strong winds. So it should be interesting…

I spent time today working on some comics stuff. And then this evening was the 4th lecture in the image processing course which I am tutoring. It was good that I worked through the exercises on Sunday, because this week a lot of students needed help. It was a tough one fo them to transfer the theory from the lecture into the practical understanding and code needed to answer the exercise questions. So I had to bounce around in a lot of different teams on MS Teams, answering a lot of questions, and giving the students pointers to how to get started. I really earned my pay tonight!

New content today:

Corners and features

COVID update: 830 new cases in NSW, another new record. Australia has never had case numbers this high. This right now is the worst part of the whole pandemic for Australia, and it’s only going to get worse for the next few weeks. But enough on that for today.

Yesterday morning for breakfast I made sourdough pancakes:

I’ve been making sourdough bread every few days as needed, and in between keeping the starter in the fridge. But my friend who got me started on sourdough says he keeps his starter out at room temperature, and feeds it every 2 days, and so generates some excess starter, which he then keeps in the fridge until he uses it for some other thing… such as sourdough pancakes! The other thing to know is that his bread constantly turns out very airy, with large air bubbles, while mine is always very dense, with only tiny air bubbles. So I wanted to try to emulate what he’s doing a bit more to see if I can get my bread to rise more. The result was I ended up with leftover starter at the end of the week, so I tried sourdough pancakes for the first time. And they turned out really good!

The other feature here is the strawberries. There is currently a huge oversupply of strawberries in Sydney, apparently caused by the COVID lockdown. Everybody is buying groceries online (either for delivery or “click & collect” pickup), rather than browsing around in the supermarkets. And apparently strawberries are primarily an impulse buy – not something that people add to their baskets when doing grocery shopping online. So nobody’s buying strawberries. And so the price has crashed… I picked up three punnets for what I would normally pay for just one. I might get more this week if the price is still low.

Today I worked on getting up to speed with the next lecture in the image processing course I’m tutoring on Monday evenings. Lecture 4 is on feature detection in images, primarily Harris corners and SIFT features. While I know about these things and had a basic understanding of them in my time at my previous job, I’d never fully internalised exactly how they work, at least not to the point where I could remember the details. So I had to do some reading up and make sure I understand the basic principles and how to implement them. And then I tackled the tutorial questions for the week, writing some Matlab code so that I have a ready-made solution which I can explain as necessary to students who need guidance at various stages. It took me well more than the hour that the students have assigned to this task!

After finishing that, I worked on assembling comics in time for Monday. I’m cutting this batch pretty close to the bone – I’ve been so busy with stuff lately that I couldn’t get to it earlier to ensure a comfortable buffer.

The other thing of note today was the weather. It was warm. Sydney recorded 25.4°C, up to 28.6°C in some suburbs. It was also very smoky, with hazard reduction burns being carried out in several forest areas around the city outskirts. The northerly wind blew this into the city, and where I live it varied between barely noticeable to strong smoke smell and dull orange sunlight throughout the day. The forecast for tomorrow is even warmer, up to 27°C in the city.

And it’s still winter. We’re starting to wonder what this summer is going to be like.

New content today:

Australia’s worst day

Today New South Wales reported 825 new COVID-19 cases in the previous 24 hours. This number by itself exceeded the previous record high number of cases recorded in the entire country for the entire pandemic so far. Add in a handful of other cases in other states, and it was easily the single worst day for Australia yet recorded. And there’s no sign of it slowing down, despite the introduction of further lockdown restrictions.

Parts of Sydney now have a night time curfew, although not the area where I live. Outdoor exercise is now limited to a maximum of one hour per day. And we now must wear masks at all times outdoors, except if doing vigorous exercise. Which means essentially that the only place I can not wear a mask is inside my own front door.

The Government’s message has changed over the past few days. It used to be trying to reduce the numbers of this outbreak, in an effort to get cases close to zero again. But now it’s turned to “keep things under control until November (when 80% of the population should, be vaccinated)”. It’s changed from “eliminate the virus” to “live with the virus”. It’s frustrating and sad to see this change of attitude in the government, after their abject failure to keep the delta strain under control when the outbreak began. Everyone dying now, and everyone who will die from the cases piling up every day, didn’t have to if the government had done their job properly 12 weeks ago.

New content today: