Artificial Intelligence Planning

I’m effectively done with Artificial Intelligence Planning, an MOOC offered by the University of Edinburgh on the Coursera platform. It’s taught by Gerhard Wickler and Austin Tate. I originally took it because I have some interest in AI in games and because I’d participated in the AI Challenges of the University of Waterloo Computer Science Club. As it turned out, the course is probably a bit too general and too theoretical to be really interesting or useful to me. The algorithms are taught exclusively in pseudocode and there are only two programming assignments throughout the whole six weeks of the course.

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Recent Interesting Science Articles (January 2014)

The first of the series for 2014. It’s a light start for the year:

  •  First, we have this New York Times article covering a study that looks into how technology might be changing how people interact with each other. This one works by filming public spaces in New York and comparing them to similar footage filmed forty to fifty years ago. The researchers carefully identified persons in the footage that were observed to be using mobile phones and similar devices and tried to draw comparisons between then and now. It turned out that publicly visible usage of such technology was lower than they expected and that mostly by loners. They also found that more people are meeting and loitering in public spaces and speculate that technology may be a reason for the boost.
  • Next, this Atlantic article talks about how even sleep has a placebo effect. In the study, scientists informed participants that REM sleep is more restful and getting more REM sleep is correlated with better performance on learning tests. They hooked up the participants with sensors and told them that this would measure the amount of REM sleep they had gotten the previous night. This was however a lie as the scientists had no way of knowing that fact. Unsurprisingly, it turned out that participants who were told that they had gotten more REM sleep did perform better on cognitive tests compared to those who were told that they had gotten less REM sleep than average.
  • Finally, here’s a direct link to a paper that seems spurious but actually makes perfect sense. The idea is to search for time travellers from the future by searching for prescient content on the Internet. This includes content about events that preceded the date of the event and search engine queries about events before the events could possibly have been known about. Not surprisingly, the search revealed no evidence of any time travellers on the Internet.

Worm Web Serial

So I finally finished reading Worm, a massive web serial that clocks in at over 1.6 million words. That’s easily over a dozen regular books. Like many others, I was drawn in by Eliezer Yudkowsky’s recommendation. It’s a superhero story with a teen-aged girl as its protagonist. It starts out on a small scale in a high school setting and could easily be dismissed as yet another Young Adult story. But as you read on, the camera pulls back and you realize what a massive and well-developed world this story is set in, with tons of characters each with intriguing side stories of their own.

Soon enough our protagonist becomes embroiled in ever greater and more earth-shaking events and the whole thing ends with a massive battle that redefines what it means to be epic in the superhero genre. This story pretty much has everything that any fan of superheroes could want: inventive superpowers and more importantly, creative uses of said superpowers, superb character development and very satisfying inter-character interaction, masterful handling of tension and cliffhangers, a rich setting with mysteries such as the origin of superpowers that are slowly explained over the course of the story, giant kaiju-style threats that all characters must team up together to drive back, and a fantastically written overall arc that must have been planned right from the beginning.

Perhaps more impressive than all that is that the author apparently managed to finish all this in about two and a half years of work, cranking out chapters twice every week like clockwork. Later he used bonus interlude chapters as incentives to drum up donations, so many weeks had three chapters. Early chapters were pretty short in the 3,000 to 4,000 word range, but chapters grew in length over time so by the end 8,000 word chapters were the norm and 10,000 word chapters were not unheard of. That is an inhuman level of dedication and hard work over such an extended period of time.

I do have plenty of complaints and nits to pick but I would like to make it clear that this is a fantastic piece of literature and I don’t want my negative comments to discourage readers from reading it so I’ll refrain from listing them here. It still needs editing and some revision but I sincerely believe that this epic deserves to be published and sold alongside A Song of Ice and Fire, the Harry Potter series and works of similar stature. If we’re very lucky, very lucky, we might even see movies or television shows based on this many, many years down the road (though given the scope of some of the fights, I find it hard to imagine how one would go about filming the scenes).

Now go and read it. You’ll be enthralled.

Recent Interesting Science Articles (December 2013)

No less than four article this month, which makes for a good store of reading materials:

  • The Guardian has an article on yet another anti-ageing breakthrough. This one focuses on a compound called nicotinamide adenine dinucleotide which apparently restores the communications system between the mitochondria of a cell and its nucleus. The dramatic results of trials with mice were that two-year old mice which were given the compound had their ageing indicators reversed to that of six-month old mice. As usual, this is just a very narrow result that has been vastly generalized for popular news consumption since the ageing process involves many more factors and it looks like this applies only to muscle cells. But it’s still one more step in the fight against mortality.
  • It is well known that humans have specialized brain structures for facial recognition. This article from The Independent showcases research which suggests that dogs not only have similar skills to recognize the faces of other dogs, they may also be capable of recognizing the faces of their human owners. The results were based on the usual metrics of observing which images dogs’ eyes were focused on and how long their attention lingered on each image. Especially notable is the observation that dogs still preferred looking at the faces of other dogs rather than the faces of their owners.
  • The Scientific American has an article that has immediate, practicable use to anyone who uses social networking. It details research on something called the cheerleader effect which causes faces shown in images to be perceived as being more attractive when they are presented in a group. In other words, you look better in a photo when you are surrounded by other people compared to when you alone in a photo. An associated effect is that the impression that viewers have on the group as a whole influences the perception of any individual who is part of the group. This means that if you want to cultivate a specific impression on other people, it would be useful to have photos taken of you in the company of other people who can convey the image you want.
  • The placebo effect is something that most readers of this blog should be familiar with and it is an essential element that needs to be taken into account when considering the efficacy of drugs and medical treatment. This article from The Wall Street Journal talks about fake knee surgery seems to be work just as well as real surgery to reported pain and other symptoms in some patients suffering from torn knee cartilage. The trials involved patients who underwent the actual procedure and control patients who did not undergo the procedure, but efforts were made to make it seem like they did, for example by pressing instruments against their skin and keeping them in the operation theatre for the exact same length of time. They found that those who underwent the real procedure had slightly better short-term results but there was no difference between the two groups after one year had passed, suggesting that natural healing worked just as well.

Recent Interesting Science Articles (November 2013)

Just three articles for this month.

  • This is an amusing article that appeared in The Economist. It’s about research that demonstrates that dogs have lateralized brains, meaning that the left and right sides of their brains work differently. The specific claim is that dogs wag their tails to the right when they encounter something that they like, which should be interpreted as a friendly greeting and to the left when in the presence of potential threats, which could be interpreted as a warning. Not only was this difference in behaviour observed under controlled conditions, but measurements of anxiety levels also correlated with this finding. As you might expect, I immediately tried to note if I could detect such differences in behaviour in my own dogs but I must report failure. It is simply too difficult to consistently determine which side a dog is wagging the tail towards.
  • The next article is from the MIT Technology Review and talks about how quantum mechanical effects come into play in photosynthesis, or light harvesting, as this article seems to want to call it. Specifically this article covers the transformation of light into chemical energy inside the reaction centres of pigment proteins in green sulfur bacteria. The interesting part is that the transformation cannot occur under classical physics because it would take too long for the light to find the reaction centre by randomly bouncing around inside the protein network. So instead, the light travels a variety of routes through the network at the same time and the superposition collapses at just the right time to deposit the energy at the reaction centre, which is why the process is so energy efficient.
  • Finally, here’s a great feature article on the origins of umami from Smithsonian.com. As the article points out umami is chemically very similar to the sodium salt of glutamic acid, better known today as monosodium glutamate. However while MSG has a terrible reputation among the health conscious, most people do not seem to regard umami in the same way. The article also points out that the poor reputation of MSG is probably undeserved. While people can be allergic to MSG, and these people should certainly avoid it, studies have failed to consistently find evidence of deleterious effects and the consensus today is that it is generally safe despite early results indicating that it may cause brain lesions. The article even goes on to suggest that its poor reputation may be linked to racism since many people in the United States first came to know of MSG due to its prevalent use in Chinese restaurants.

Initiation à la programmation (en C++)

This is French language introductory programming course conducted by professors from the Ecole Polytechnique Fédérale de Lausanne (EPFL). I took it for two reasons. One, it teaches C++ and it’s kind of embarrassing to know programming but not to know C++ (or at least C). Two, it’s in French and it’s good to brush up on my language skills once in a while. While this is indeed an introductory course that assumes no prior programming language, it uses C++ and as we all know, that automatically makes it a step higher difficulty. Also, since there no similar courses on Coursera for C++, quite a few English speakers apparently signed up for it despite having only limited proficiency in French.

As you might expect this course starts from the very basics: variables, expressions, conditionals, loops, functions, collections etc. But it also moved on to territory that I found surprising in an introductory course: multidimensional arrays, structures and even the dreaded pointers. There are approximately an hour and a half of video lectures per week over the course of the seven week course, the usual Coursera quizzes and five programming assignments. The assignments are autograded and actually each assignment includes multiple questions and therefore different programs. The course offers a certificate based only on completion of the assignments.

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Recent Interesting Science Articles (October 2013)

Here’s the October 2013 instalment of my regular feature:

  •  Recently a lot of attention was paid to news about a new breakthrough towards the treatment of Alzheimer’s disease. Rather than link to the more mainstream accounts of the research involved however, here is a fairly detailed explanation of what was actually discovered. The idea is that when brain cells are invaded by a virus, misfolded prion proteins build up causing a defence mechanism to kick in that dramatically reduces the production of new proteins. But in the case of prion diseases, this backfires and actually causes even more misfolded prion proteins to accumulate. The new research then covers the usage of a new molecule that inhibits this defence mechanism, called unfolded protein response. In trials involving mice, they found that by the time all of the untreated infected mice reached critical stages of disease, the treated ones were still free of symptoms. Unfortunately as this blog post points out, the mice were not monitored for longer than that because the treated mice developed prediabetic symptoms that included increased blood glucose and weight loss. Animal welfare rules in the institution required that these mice be sacrificed rather than prolong the study, so it is unknown if the drug can successfully prevent the development of prion disease for a longer period than what was observed and it is equally unclear that it is even possible to develop a viable treatment without such debilitating side effects. Personally, I find this blog post especially interesting as an example of how to look past at the hype and exaggerations in the mainstream media that initially reported and actually look at the real facts.
  • Next here’s a lighter piece about the discovery of a so-called free-floating planet in space, that is a planet-sized object that is not a star and yet does not seem to orbit any star. The object which has been dubbed PSO J318.5-22 is located about 80 light years from Earth (which is probably why we were able to detect it given its cool temperature) and has a mass of six times that of Jupiter. Large for a planet, but far too small to be a star. It is the only such object found so far.
  • This article talks about how a team managed to get photons to interact with each other, a feat that has not previously been achieved. Essentially they fired single photons into a cloud of extremely cold rubidium atoms. As the photons move through the cloud, it excites the rubidium atoms causing the photon itself to lose energy and slow down. The team then found that two photons that were fired into the cloud, exited the medium together as a single bound molecule, representing a new form of matter that has been theorized to exist but never before observed.

The unexamined life is a life not worth living