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Monthly Archives: February 2006

Farewell, Canberra. Hello, New Zealand.


Lake Burley Griffin

So long, Canberra, you bird-dominated and oddly quiet little artificial city on an artificial lake.

I went for a jog last night through the city center and saw maybe a dozen people. Somewhere in the distance a band was playing a low-energy cover of David Bowie’s “Heros”. The air was warm and humid and smelled nice, and little blue birds fluttered through the park around Lake Burley Griffin. Somehow, it all kind of summed up the Canberra experience.

I have no idea when I’ll next have internet access and time to blog. Right now, I’m looking forward to a couple of days of being able to relax and play and sleep in.

MLSS ’06


Mlss06-SnipSo, the 2006 Canberra Machine Learning Summer School is winding down. This is the second-last day. The past couple of weeks have been pretty intensive — four two-hour sessions most days, plus my volunteer duties. But I’ve learned a lot. Hearing Bernhard Schölkopf and Alex Smola talk about kernel machines made me bump their book way up on my to-read list, and Olivier Bousquet’s short course on Learning Theory has filled in a few of the many, many gaps in my knowledge.

Probably the most inspirational talk for me, though, was Satinder Singh’s talk about Reinforcement Learning (one of several RL speakers). Not only is he an excellent lecturer, he is very interested in figuring out how to bring Machine Learning (and RL in particular) back from being a kind of “reckless Statistics” to AI, which is something I’ve recently been giving a lot of thought to. So instead of using the framework of Operations Research and Control Theory, he suggests rethinking the ideas we have of states, actions and rewards in an AI framework — using variable times for actions, for example, or using thinking of reward as something internal to an agent rather than it’s environment. So for example, instead of a robot getting a reward for reaching a goal position, it could get rewards for exploring new parts of its environment, or for taking actions that produce unexpected results — being rewarded for acquiring domain knowledge, in other words, even if it’s not directly related to any specific task. And then, once the result of an action is learned sufficiently that the result is no longer surprising, it ceases to be interesting, but the agent maintains that bit of domain knowledge.

I was particularly interested to see Michael Littman’s talk on RL, since I know he has some different views, but unfortunately, he was caught in the blizzard of aught-six and didn’t make it.

I found the most useful part of the school has, however, been talking to the other students, most of whom are around the same point in their academic career as I am, or a year or two further along. Not only do we get to exchange great gossip about our respective supervisors, but it is often a lot easier to learn by discussing things with other students than by being lectured at, and it’s cool to find out about research that’s happening “on the ground”, so to speak, in the labs and grad offices the world over.

Link

As Promised, Pics of Yellow-Headed Canyon Dwellers


the yellow-helmet people

Muchly delayed, but finally up.

Link to photoset.

Also: link to my entire Sydney/Blue Mountains photoset.

Canyoning and the Blue Mountains


So last weekend I went to Sydney to meet up with Amy, and we drove out to the Blue Mountains. For those unfamiliar, the Blue Mountains are a broken, primordial land of twisted Eucalyptus forests and kilometer after kilometer of sheer cliffs rising tens or hundreds of meters straight out of it. If there’s a more lost-worldy place on the planet, I don’t know what it is. It was practically a disappointment to not see flocks of Pteranodons soaring over the treetops on leathery wings.

So what did we do? We went canyoning! Well, Amy discovered it and organized it and booked it, which was a good thing, because once I found out it involved donning a wetsuit and helmet, strapping all your gear to your back and abseilling down a 33m cliff to the bottom of a 3m-wide canyon filled with snakes, lizards and icy canyon water, I was, let’s say… apprehensive. However, it it turned out to be fantastic fun. We were accompanied by our very Australian guide and a young Danish couple who, due to an accident of translation, thought they were going canoeing.

We swam on our backs, as instructed by our guide, and looked up at the tiny sliver of sky above. We saw ferns that were hundreds of years old, since bushfires never reach damp canyon depths. We saw lizards: water dragons and bluetongues, but if there were snakes, we never saw them. We jumped (without gear) off a cliff into a pool of deep, dark water. I woke up the next day still exhausted, and sore from head to foot. Amy wanted to do a four-hour cliff hike. We did not do that hike.

Anyway, pics will be up soon, but we used disposable waterproof cameras, so they need to get all developed and such.

Canyoning and the Blue Mountains


So last weekend I went to Sydney to meet up with Amy, and we drove out to the Blue Mountains. For those unfamiliar, the Blue Mountains are a broken, primordial land of twisted Eucalyptus forests and kilometer after kilometer of sheer cliffs rising tens or hundreds of meters straight out of it. If there’s a more lost-worldy place on the planet, I don’t know what it is. It was practically a disappointment to not see flocks of Pteranodons soaring over the treetops on leathery wings.

So what did we do? We went canyoning! Well, Amy discovered it and organized it and booked it, which was a good thing, because once I found out it involved donning a wetsuit and helmet, strapping all your gear to your back and abseilling down a 33m cliff to the bottom of a 3m-wide canyon filled with snakes, lizards and icy canyon water, I was, let’s say… apprehensive. However, it it turned out to be fantastic fun. We were accompanied by our very Australian guide and a young Danish couple who, due to an accident of translation, thought they were going canoeing.

We swam on our backs, as instructed by our guide, and looked up at the tiny sliver of sky above. We saw ferns that were hundreds of years old, since bushfires never reach damp canyon depths. We saw lizards: water dragons and bluetongues, but if there were snakes, we never saw them. We jumped (without gear) off a cliff into a pool of deep, dark water. I woke up the next day still exhausted, and sore from head to foot. Amy wanted to do a four-hour cliff hike. We did not do that hike.

Anyway, pics will be up soon, but we used disposable waterproof cameras, so they need to get all developed and such.