The 5th day of GECCO (friday, 10th) was the first day of paper presentations. With only two days of paper presentations (as compared with the three days of GECCO 2008), it felt hard to attend to all the presentations I wanted to. I’ll probably send an e-mail to the GECCO organizing comittee suggesting that they spread the presentations a bit more next year.
Also, since I had to present two works in different sessions, my choices were further limited. Oh well. Anyway, the first session
I attended was “Financial Applications 1″, with two works by Chris Clack, Wei Yan and Ghada Hassan from UCL, which were extensions of their works in the previous edition of GECCO. I particularly like Ghada’s work, which focuses on not allowing a pareto front of solutions to “switch places” (move to a different area of the pareto front) when the environment changes. There was also a work on using developmental solutions for stock trading, which I still have to read more closely (TODO: and refer it to my trading colleagues in the lab).
The second session was the RWA best paper, where I had to present the work on generating trading rules with GP by my labmate Hirabayashi. Unfortunately, as Murphy would have it, my laptop and the projector decided that they don’t really like each other, and would cut communication between each other every few minutes (even though I checked everything and it was alright just one hour before :-(). Oh well. After the presentation, I made the acquittance of Stefan Haflidason, a very pleasant fellow from the UK. We had lunch together and talked about his plans to do a Post Doc in Japan.
In the afternoon, I wanted at first to go to the “GECCO Job Shop”, where poor grad students looking for work would supposedly meet with people with open positions… but no one was in the room. Instead, I had the pleasure to attend to the HUMIES award presentation. The HUMIES is a competition of research works on evolutionary computation which are not only effective, but competitive with human habilities in fields which are traditionally dominated by humans. There is a cash prize to the best work, and all the presentations were of very high quality. Among the candidates, the ones I found most interesting was a system that could find and correct bugs in programs - which was demonstrated on outstanding bugs in varied open source projects! Obviously that one won the prize this year. Other works that I liked were a system that generated malware programs, and a system that used IEC to generate drum accompainment to musical pieces. On a more light hearted note, one of the presenters sounded just like Dr. Strangelove - so much that I was half-expecting his hand to grab his throat at any time during the presentation.
The last session I attended to was second financial applications session, where I presented my own work on Memetic Algorithms for Portfolio Optimization. This time, the laptop and the projector respected each other, and the presentation ran without a glitch. I had a number of questions, and it was a very fine experience.
After the day was done, I tried to get together a largish group of people to go and walk around Mt. Royal - but ran into a complicated constraint satisfaction problem. A group of Romanians wanted to go walking, a group of Japanese wanted to go by train, and everyone had different ideas about how hungry we were. In the end, we separated our 15 people group in two: one to go walking, and one to go by train, and decided to meet by the entrance of the park. By a freak accident of destiny the walking group got to the meeting point before the group that would go by train, which led me to believe that we missed the meeting point. Me and Stefan tried to find the train group, and in doing so, we missed them completely (they got to the meeting point 5 minutes after us) - when we returned, the Romanians had returned home, some people already had dinner, and nobody wanted to go to Mt. Royal anymore :-P. Me, Stefan and about 10 Japanese went to a nearby American-style diner, and managed to salvage the night with some nice lasagnas. After so much walking, I returned home and slept like a stone.
The next day, Saturday, was a bit overcast. The first session I attended was on “Dynamic Environments and Aging” - and it had two papers which were quite relevant to my work. One was the use of ALPS (age-layered population structure) to maintain diversity in the population for Real-Valued problems (by Gregory Hornby). The basic idea of ALPS is to give each individual in a GA an “age” (based on the evolutionary operators it went through), and separate the population into age layers, so that only individuals in the same layer could mate to each other. One interesting point in this particular work is that older individuals tended to be more complex and solve the problem better, and it was suggested during the discussion stage that individuals in different age layers could be trained in different, and progressively difficult, problems, to achieve some sort of developmental property. I found this idea really cool. The second paper which I found relevant was about “Terrain-Based Memetic Algorithms” (TBMA) by Carlos Azevedo and Scott Gordon (couldn’t find any links handy, sorry). The basic idea was to generate a grid, and distribute the individuals of the population in the grid - individuals could only mate with other geographically near individuals. Then for each position in the grid, you assign different parameters for the local search of the evolutionary algorithm. In this way, the movements of the individuals over the grid as they mate and are selected by the fitness function will lead to a self-adaptation of the best LS parameters (the grid locations with the best parameters will attract individuals). I found that this idea can be expanded in a very neat way to my project (and I still have to contact the authors to talk about this.)
After the DEA session, I attended to the game session where I saw Omid’s wonderful presentation about his computer chess player. He has this very simple and elegant idea to train chess positions evaluators using a database of movements from a human grandmaster. In a way, he is reverse engineering the mind of Kasparov. The impressive thing about his current work is that training multiple times on the same dataset, he got a number of chess players with different characteristics. Since he reported that none of his chess players managed to get more than 40% of the answers right, I’m guessing that the difference comes from learning different parts of the database that correspond to different styles of play from the same player. So I guess it is not even possible to go much above this threshold, since the “evaluation” function used by the grandmaster may have been actually quite different for different groups of moves. It is a fascinating work and I can only guess at what Omid will come up with next year.
For lunch, I went back to lovely Rue St. Denis, and to the “Valet du Cour” game shop, to buy a deck of cards that Leon had asked me. I also bough myself a plush green dragon - I couldn’t resist the little beast.
It started raining, and I took shelter at local Cafe. All the waiters could speak mostly French with some pidgin english, and I felt a bit ashamed for not being able to communicate properly with them. Need to learn more languages - or at least make an effort to learn the basics out of a phrasebook before visiting other countries.
Because of the rain, I didn’t make it back in time for the third session in that afternoon. I arrived a few minutes before the end of the session, and while I was browsing the net in the lobby, it was curious to observe the network getting considerably slower when the session ended and the influx of geeks turning on their laptops began.
After that we had the plenary session, with a talk by professor Demetri Terzopolous - It did not have anything to do with evolutionary algorithms, but I guess that is kinda the point of a plenary session, right? Demetri talked about is works on the simulation of individuals and societies, describing the framework for realistic simulation of complex creatures, from the physics level to the structural, muscular, reactive and behavioral levels. Plenty of pretty pictures and animations too (Although it got a bit awkward when he showed that strip scene from Animatrix).
At night, we had the main reception at the Montreal Science Center. It was supposed to be GECCO’s 10th birthday, so we had a cake and fireworks (not provided by SIGEVO *g*). It was a good chance to shake hands and talk to many people I had not yet had the chance to meet. In particular, I was introduced to Nuno Horta and his student Antonio Gorgulho, who used my master thesis in some of their earlier works - It may be kinda silly, but it felt nice to know of someone who studied your works!
After the party, I went with Mark and Jeff and a few others for some extra drinks in a bar in old town. It rained quite heavily while we were looking, and none of us had umbrellas, so when we finally picked a place, we were quite drenched. I didn’t stay for long, for I was quite tired, but I heard they had a terrific time there.
And that’s for 5 and 6. Sorry for the delay! I’ll try to get the last part of my travel log online soon, so we can get on with our regular schedule! (I have postponed some stuff I wanted to talk about until I could get these GECCO posts finished).