ALife day 3

Day 3 of ALife, and the great science continues!

First up was the keynote by Jorge M. Pacheco, on “Linking Individual to Collective Behavior in Complex Adaptive Networks”. A nice discussion of investigating iterated prisoner-dilemma cooperation-defection situations where the agents are distributed over social networks. Agents can change their behaviours (from Cooperator to Defector or v.v, by copying the strategy of their most successful neighbours), or change their network (both Cs and Ds want to drop connections to Ds, but Ds want to make connections to Cs). Interestingly, it seems that changing the network (changing who your friends are) is more effective than changing your strategy (changing what you do). So it’s best to isolate defectors. (Hmm.)

Next was the morphology session. Although several of the speakers admitted their work wasn’t truly about morphology, all the talks were all interesting. We heard about difficulties of co-evolving morphology and body controllers. Morphology seems to converge quickly, because if it changes, the co-evolving brain can’t adapt fast enough. The speaker had some suggestions on how to improve the situation. Next we heard about evolving soft body robots, exploiting “passive dynamics” and using this capability as a sort of embodied “computational reservoir”. Then there was an examination of how the shape of space (a “donut” shaped torus v a “bicycle tyre” shaped torus) affects iterated prisoner dilemma: donuts are better. Then finally there was a nice talk about co-evolving predator field of view and prey “swarminess”, with interesting Red Queen style oscillations: prey evolve to swarm to confuse the predator, which evolves a narrower field of view to avoid confusion, so the prey then evolve to scatter to hide from the focussed predator, which evolves a wider field of view, and so on.

The second keynote of the day was Mark Bickhard, talking on “Cognition and the Brain”. In a brilliant talk, he covered what it means to be an anticipatory system (having a set of possible future actions to choose from), and how that can allow representation to be true or false (to see if a representation is true, wait and see what the future brings). The talk wove together this philosophy with details about microstructures in the brain, particularly the possible role of glial cells being large scale slow processes that modify the attractor landscape of the brain to influence smaller scale faster neural processes. The whole approach sits within a process philosophy, which permits the emergence that duality is designed to make impossible. I now want to go away and simulate the nested oscillator modulatable resonant architecture he speculated might underlie these processes.

The final session of the day was on computational biology, with a range of talks covering the self-organisation of badger latrines, chopping the tails off tadpoles, making C.Elegans models that swim correctly, a multiscale simulation of E.Coli (from molecular to Petri dish scales), and experiments on the evolution of genetic networks. That’s quite a varied bunch!

ALife day 2

Day 2 of ALife, and more great science!

First was Ezequiel Di Paolo’s keynote on “Gilbert Simondon and the enactive conception of life and mind”. There are a lot of French philosophers whose work is relevant to complexity and systems and ALife who I have heard of but not read (Gilles Deleuze, Maurice Merleau-Ponty, Edgar Morin), but Gilbert Simondon was one I hadn’t heard of (and so presumably haven’t read, either). As I understand the presentation, Simondon was critiquing the duality of matter and form: form is intrinsically embodied in the rich physical material. Examples range from bricks, turbines, to life itself. The systems more and more exploit the rich embodied properties of their material embodiment. There is a process of individuation, or taking of form, but it is the process, not the end-point, that is key. There is a pre-individual state full of potentialities, which are exploited during the individuation process, and the fully individuated system has no more potentialities, and so is “dead”. Matter is more than mere stuff, it includes potentialities, transformations, operations, and changes. There was a lot more in the talk, all fascinating. I may have to start reading this particular French philosopher!

I didn’t get to go to any of the morning technical sessions, as I was in a committee meeting. So the next thing, after perusing the posters in the reception area, was the next keynote, Alexandra Penn’s, on “Artificial Life and Society: Philosophies and Tools for Experiencing, Interacting with and Managing Real World Complex Adaptive Systems”. Alex described how her group was using a participative approach to systems modelling, including diverse stakeholders. The models built are deliberately rough and ready, partly because there is no hard data, but partly to make it easier for the stakeholders to challenge them. Modelling allows for the discovery of relevant factors, and for diverse stakeholders to appreciate each other’s concerns. Analysis of the resulting models then allows the exploration of scenarios and identification of system levers. Since the system will respond to manipulations, there needs to be a continual modelling and monitoring process. The metaphor is system steering, rather than system control.

Then it was off to the snappily titled “Synthesising Concepts from Biology and Computer Science” (SCBCS) workshop. This was a bunch of short presentations about potentially suitable areas for writing review articles: diversity, fitness, open-ended evolution, self-modification, plasticity, modularity, recombination, co-evolution, Each of these areas is important in computer science (“natural” computing) and in biology. What could each discipline learn from the other? I find review articles that engage in deep synthesis some of the most valuable publications: they bring together small patches of research, and actually build the subject area. A good review is not a mere “annotated bibliography”: it is a constructive part of science itself. I am not qualified to contribute to many of these proposed articles, but I certainly want to read all of them! If only half the proposals were to be taken forward, it would be an extremely valuable contribution to the relevant disciplines.

So, another day, another ton of thoughts to process.

Open Ended Evolution workshop

Today at ALife was OEE2 – the second Open Ended Evolution workshop.  There were 12 presentations followed by a discussion.

I got to go first (which is always the best, as I can then relax and concentrate on the rest of the talks). I was presenting our recent work on defining open-endedness by giving a definition of novelty in terms of the model and meta-model of the system being observed.  It turns out that there may be a connection between this definition and some definitions of creativity.  I’ll have to chase up some more references.

There were some interesting themes running through the day. I’ll pick out just a few that I found resonated particularly well with me. One theme was on infinite (or maybe better unbounded) scalability: make sure there are no limits designed into the system, because they will, sooner or later, stop open endedness. There were also several talks on using discrete dynamical systems as the basis for either theoretical or experimental investigations. One of these, given by Alyssa Adams, used coupled elementary cellular automata to investigate how using an “environmental” CA (E) to change the “organism” CA (O) rules could result in O displaying certain kinds of novel behaviour. Particularly interesting was that just allowing E to override O’s rules, or overriding them randomly, wasn’t that interesting, but allowing a combination of E and O’s current state to override the rules gave the interesting novel behaviours. A very elegant idea. I think it would be interesting to allow the higher level rule that changes the CA rule also to be changeable (maybe it already is; I need to read the paper). And connecting to the unbounded scalability theme: maybe there should be a rule governing the size of the CA to change, so that the size of its state space can grow unboundedly (although would then make the character of the current analysis somewhat different).

Nathaniel Virgo gave a talk about a modification to Fontana and Buss’ lambda-calculus artificial chemistry. The original in irreversible, and collapses to a boring system unless effort is made to exclude certain kinds of reactions.  Nathaniel added an extra kind of reaction, making the overall system reversible (in that it doesn’t lose information about the kinds of particles originally present). This seems to have solved the boringness problem in a straightforward manner. Not only does the new system build interesting reaction networks, it builds interestingly different ones each run, rather than having some average behaviour. The intuition is that the reversibility allows the system to “backtrack” if it gets stuck somewhere, and explore a different path. Presumably the fact that the state space is so huge means that the new path can be significantly different in character form the old path. To start with, any approach that does not destroy information might be fine, but eventually, in order to build in an analogue of thermodynamics and Gibbs Free Energy, reversibility will be required.

The presentations were rounded off with a thought-provoking one by Ken Stanley. He was arguing that OEE systems need to be “interesting”, and that “interestingness” is subjective. As an example, he asked us to consider a though experiment. Suppose there was some agreed-upon complexity metric C that we could use to determine how complex or whatever a particular string is. Then do a random, or exhaustive, search over strings of length M to find the best on. Then repeat for strings of length M+1, M+2, …. The result will be a sequence of the best strings in ascending order of length: a form of open-endedness in some definitions. But would that sequence be interesting? He claimed not, and that there also needed to be some narrative about the process of discovering those strings to make the result interesting (to us). Some in the audience disagreed: they would be interested in those strings! Let’s think of something like a complex work of art. We might find it intrinsically interesting, knowing nothing about how it was produce. We might find it more interesting if we also knew the history: but that’s a “bigger” system, art work plus historical context, so it has the opportunity to be more interesting. Additionally, there’s the interestingness of the metric itself: how was that decided upon? Is it even computable? Then there’s the sheer scale of the problem: exhaustive search quickly runs afoul of combinatorial explosion: the process would never actually work. The narrative of how the strings were found in an evolutionary or other manner is interesting partly because it tells us how this combinatorial explosion of exhaustive search was avoided in this case.

The day finished off with some summary and discussion,and we all went away with our heads buzzing with new ideas, and old ideas looked at in a new way.

out in the heat

I applied sun screen / insect repelant combo, and went for a stroll.  I managed half an hour outside in the heat (despite staying in the shade where possible) before I needed to return to the inside coolth.

I saw some interesting birds, that looked like slim blackbirds with longer legs, and a long triangular tail:

my Google-fu tells me this is probably a Great-tailed grackle

Also, what looked like some kind of parasite growing on a palm tree:

parasite? with fruits? growing half way up a palm tree

That was enough heat, and I returned to the hotel, and went up onto the roof, where there is better view than from my window:

view from the roof; turquoise and blue sea

After a chat in the hotel with some other conference goers, it was time to venture out again, for lunch.  Off to Mocambo, a Mexican seafood restaurant, with an "indoors" that was actually open, but under a thatched roof, with views over the sea, and accompanying welcome sea breeze.  Delicious food, a great view, plus pelicans flying by!

view from a hotel window

I arrived in Cancun, Mexico, yesterday evening, ready for the ALife conference starting on Monday.  There were several ALifers on the flight...

The flight landed a 6pm local time, only half an hour late.  (I say "only" because we took off an hour late from Gatwick, despite being all boarded on time.)  Then there was a long queue at immigration.  Then outside (bam! the heat!) to find the shuttle bus.  "It will be the guy wearing an orange tabard, holding a sign."  Am I grateful for that, as there were a zillion guys with signs, but only one with an orange tabard.  Then off to the hotel, in a gloriously air-conditioned shuttle bus.

I was a bit zonked by the 10 hr flight, and 6 hour time difference, but 8 hours sleep plus breakfast plus coffee, and I'm feeling human again.  Human enough to take the traditional photos from the window.

view from the window (at an angle)

view from the end of the corridor

Now off to slather myself in sunscreen/insect repellant, then explore the beach/air-conditioned restaurants.

my latest new toy

I have the teal keyboard.  It is teal, not blue.  Phone camera colours lie!

I have upgraded my travelling machine to a Microsoft Surface 4.

I started off with a little netbook with Evernote.  That worked well, and I later moved on to a more portable-friendly tablet, still with Evernote.  That also worked very well for meetings, but I discovered that when I was away for a stretch, and needed to do more than just take notes, that something more powerful would be helpful.

I was pondering what to get next when I had a meeting with a colleague who was using his Surface.  The meeting quickly disintegrated into a discussion of its pros (a laptop (so all the utils I need, including Evernote for Windows, which is better than Evernote for Android), with a full keyboard (including backlit keys, useful for note taking in darkened auditoria), and a touchscreen (with beautiful resolution), and a smart stylus, that you can use to take handwritten notes (useful for maths and figures), that magnetically clips to the device (yes, I'm that shallow), and...) and the cons (a bit heavier than a tablet, and, ... not much else I've noticed yet)  So I got one.

I'm just off to a conference, so it will get a good workout as a day-note taker, and a general purpose workhorse.  Time will tell.

stairs v bananas

Stairs no longer make you safe from Daleks, or Boston Dynamics robots.  However, there’s always banana peel…

I for one welcome our new Kermit-headed overlords.

---

For all my social networking posts, see my Google+ page