vetta project

When I was looking for a new laptop last year I appreciated reading other people’s candid views on their recent purchases, thus I thought I’d write a post to contribute back.

I ended up getting a Lenovo T61p. Specs: Core2 Duo T7500 at 2.2Ghz, 4 GB of RAM, 1680×1050 screen, nVidia Quadro FX 570M graphics card with 256 MB, and a 9 cell battery. One factor in making this decision was that it was discounted through the university by about 30%. It came with 32 bit Visa Business and I installed Ubuntu 7.10, which I’ve now upgraded to Ubuntu 8.04.

Perhaps the biggest factor for me was reliability. Laptops seem to have a tendency to break and that’s a major pain to have to deal with.  Unfortunately, after a few months of talking to people about their laptops I came to the conclusion that a significant proportion of all major makes and models have problems (and yes, that does include Macs… Jesus, you guys are worse than Jehovah’s Witnesses). All I can say is that after half a year I have had no hardware failures, of course your experience might be different.

The good:

The screen rocks. It’s 15.4″ 1680×1050, which gives you about 130 dpi and is still plenty bright. To start with I wasn’t sure about getting such a high res screen as it might make things too small. However, I just set the dpi in Ubuntu and everything rescaled up, i.e. all the fonts and menus etc. are the same size as normal but are now exceptionally clear and sharp. Sadly these high spec screens are not an option in all countries for some reason.

The keyboard is great and I now understand why people rave about ThinkPad keyboards. To start with I wanted the Fn and Ctrl keys swapped, however after a week I no longer noticed.

The chassis is the best I’ve ever had on the laptop. It’s all reinforced with magnesium so it’s super rigid. Indeed, physically the whole laptop feels very strong.

The wireless is perhaps too good? Every few weeks, usually on a Saturday morning, it’ll drop the wireless connection for a few seconds while in my apartment. However, I’ve noticed that when this happens the wireless system is reporting around 20 available networks, so I guess it starts having problems with conflicts? Seriously, I can pick up wireless networks from people’s houses half way down the street.

The performance seems good, but I haven’t really tested it against anything. As far as graphics performance goes, I know that Crysis is infamously demanding in this area. So long as I turn down the screen resolution and limit the texture size to fit in 256 MB, I find the game quite playable. Thus if it can (just) handle Crysis, I’d expect it to deal with most other games without a problem (though obviously this isn’t a high performance gaming machine).

The battery life is pretty decent. I get 3 to 4 hours depending on what I’m doing. And it’s quiet, very quiet. Even under full load it’s still pretty quiet.

The bad (or at least not-so-good):

The track pad is far too small. I’m used to using the red dot to move the pointer as then I don’t need to move my hands, so this doesn’t really bother me. However, if you’re used to big track pads you’ll hate this one. At around 3 kg it’s a bit heavy. The screen is slightly off centre to the right due to the wireless. I thought that might bother me to start with, actually I never notice it. I also thought that having the cursor arrow keys being slightly smaller than standard keys might bother me, but I got used to it. The only hardware feature I miss is not having a built in webcam for use with skype. Instead I have to plug one in. That’s about it really.

Oh, there’s also the missing DVI output. To start with I couldn’t understand their thinking in going with VGA, however now I get it: If you want a desktop set up, then get a docking station and you’ll get the DVI output from that. On the other hand, if you’re running around somewhere and want to plug into a projector, then you’ll want the VGA output anyway. Unless you manage to come across a very new high end projector, in which case you can skip the cables altogether and use the laptop’s wireless USB.

Finally a word on operating systems. It came with 32 bit Vista Business which is kind of a joke, but you knew that already. I dual boot the 64 bit version of Ubuntu 8.04 and am very happy with it. 7.10 had some issues, but with 8.04 things just work. Really.  Wireless, DVDs, all the special buttons to adjust volume and screen brightness, even the graphics system worked without me touching any config files. Once it was installed it informed me that to get accelerated graphics I’d need the closed source driver from nVidia.  So I clicked ok and it installed it for me and restarted X. The only thing that needed real intervention was getting suspend to work. I googled around a bit and found that I needed to add a line to some file to unload and reload my wireless. That fixed the problem. Even the colour laser printer down the hall now works, including the positioning of staples.  There used to be problems with flash player on 64 bit linux, but now that works too. Skype with video, also no problem. The only thing I know of that doesn’t work is wireless USB. Given that I’ve never met a wireless USB device before, it’s not exactly a problem. I guess that in a year or so when they become more common this will work.

Of course Ubuntu still has a few rough edges.  For example, I couldn’t work out how to get the VGA output to work in order to drive my projector. In the X config when I’d click on “Detect External Monitors” nothing would happen. The problem is that I’m running the nVidia stuff and thus I have to run the nVidia config software to set up more complex things like multiple monitors.  Using this software, everything appears to work.

Small update: One of my friends who’s doing a PhD here just got a new Dell laptop today and installed 64 bit Ubuntu 8.04.  Everything worked perfectly straight out of the box: wireless, suspend, sound configuration, dual monitors… everything.

After all this time, I’m finally getting to the stage of knowing enough to know how much I don’t know.  Or in Rumsfeld’s lexicon: unknown unknowns are slowly becoming known unknowns.  Equations, theorems and whole sub-fields of study that I’d previous heard mentioned, or that I’d studied and largely forgotten as they didn’t seem useful, are turning out to be essential for problems I have to solve: optimal control theory, measure theory, stochastic calculus, variational calculus, martingale theory, mean field theory, perturbation theory, kernel density estimation…  if I’d fully understood all these things to start with, I would have been able to knock off a month of work in just a few days.  :-/

As a child in school my intelligence and knowledge was my greatest asset, but as a researcher I’m finding that it’s the main thing holding me back.  If I could double my knowledge and intelligence, I could easily quadruple my productivity.

Anyway, our proto-AGI is now able to learn and abstract spatial patterns, and it should soon start forming generative temporal abstractions.  A backend for securities trading is also starting to take shape.

With the sub-prime meltdown and ensuing financial crisis, all the hedge funds are in deep trouble… right?

Apparently not.

When building simulations of rational agents trading in dynamic markets over extended periods of time, tell your optimiser to solve everything down to 1 part in 100 million. If you don’t, all those tiny little errors will start to interact with each other… and 10 years down the track bad things will start to happen.

Mathematical finance can be really highly strung.

I just saw another neuroscience paper on neural correlates of consciousness. When I first heard about this idea in a lecture series given by Christof Koch, I thought it was a good idea. I now suspect, however, that this line of research is going to produce very little. What it will probably find is that when certain areas of neurons are active in certain areas of cortex the individual is able to report this as a conscious experience. These neurons will be found to be very well connected to key higher areas of the cortex. On the other hand, areas which aren’t reported as conscious experience (e.g. dorsel stream) will turn out to not be well connected to certain important areas of cortex. In other words, if a part of the cortex is well connected to the parts of the cortex that are needed to report something, the individual will say it was a conscious experience. And when it isn’t, no report will be made.

But what does this mean? Nothing really. Like in the brains of people with a cut corpus callosum, who’s to say that there isn’t a conscious experience of what is taking place in these parts of cortex that aren’t being reported as conscious experience? It’s just that this conscious experience is not integrated with the parts of my conscious experience that are able to report. There could be a number of other “conscious awarenesses” residing in my own head that “I” don’t experience as “I” (the part of my brain that is able to report) am not sufficiently integrated with them.

That’s a pretty weird thought, and yet it seems reasonable. A touch Freudian even.

In my opinion, the biggest theoretical problem with universal intelligence is the dependence on the reference UTM. The invariance property of Kolmogorov complexity provides some protection, but it’s not really enough. Years ago I thought about a number of ways to try to remedy this. I don’t recall all the possibilities that I considered, however I do remember that I never found one that I was completely happy with.

Talking to Peter Dayan about this the other day, he suggested the following: run the test multiple times always sampling from the same reference machine and allowing the agent to keep state across trials. Over time a very smart agent will start to learn the environmental sampling distribution and thus will be able to overcome not knowing the reference machine.

I remember talking to Marcus Hutter about measuring the intelligence of an agent by enumerating from the simplest environment up. The idea being that the simplest will have the biggest impact on the universal intelligence result anyway. Of course this would open up the possibility that the agent could work out the enumeration method and then not have to “learn” about a new environment by having to interact with it. That would be cheating. If we allow the agent to learn across trials but randomise which environments it sees each time, that should allow smart agents to learn to overcome the compiler constant and yet still not allow it to cheat.

It should then be possible to prove that an AIXI agent has maximal universal intelligence even when the agent and the test use difference reference machines.

– Henry Markram in this article.

Maybe, but I suspect he will be beaten by people working on ANNs.

I’ve been invited to give a talk next week at the Gatsby Unit in London. Gatsby is known around the world for its research into theoretical neuroscience, computational neuroscience and machine learning. It’s home to famous researchers such as Peter Dayan, David MacKay and, until recently, Geoffrey Hinton. I’ll also get to spend a day hanging out in London. This is going to be fun!

Just read an interesting little article on graphene transistors. I’d never even heard of them before, apparently it’s the stuff that’s in your pencil. Anyway, with a bit of work you can make amazing transistors with it.

…electrons move through graphene with almost no resistance, generating little heat. What’s more, graphene is itself a good thermal conductor, allowing heat to dissipate quickly. Because of these and other factors, graphene-based electronics could operate at much higher speeds. … de Heer says, “I believe we can do a terahertz…”