

Winner of 2011 Google AI Challenge Describes Released Code - tvorryn
http://xathis.com/posts/ai-challenge-2011-ants.html

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icefox
I had fun playing around with the challenge and spent most of the time poking
around with map exploration as implementing min-max once again isn't too much
fun. I ended up having the most fun playing around with the idea of an anti-
object . The simplicity of anti-objects combined with the low memory and low
cpu overhead was very nice. Wrote it up in a little blog for others:

[http://benjamin-meyer.blogspot.com/2011/11/using-
collaborati...](http://benjamin-meyer.blogspot.com/2011/11/using-
collaborative-diffusion-rather.html)

Any ideas for a type of challenge that wouldn't be reduced to mostly min-max
for the ranking, but could explore other concepts?

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tvorryn
I actually used this idea from the forums and your post to get 683rd place
even though I started on it with 36 hours to go before the deadline.
<http://aichallenge.org/profile.php?user=972> So thanks.

How'd you do?

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peregrine
Now this is what I go to HN for! The most interesting part for me was that he
did not focus on some huge strategy. Just individuals and small groups with
clear goals and constant revaluation. Keeping in mind that the only thing kept
between rounds were missions and those were constantly reevaluated as well. I
think this is a vivid, albeit simplified, example of how successful
organizations of anything should operate.

EDIT: grammar

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Jyaif
What's that? You aren't more interested in the SOPA drama?

~~~
peregrine
Well I was when it was 1 day from being jammed down our throats. Then it was
postponed to the new year, at least the lobbyists in our courts(EFF, Google,
etc) have sometime to throw some cash around. And people can do something.

I do think the SOPA Drama was a bit delayed and overblown here on HN.

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DanBC
I see a few people saying that they didn't have much time (or that they didn't
want to spend too much time) for this.

Is that really actually true, or is it some kind of 'modesty'[1]?

When people talk about IQ there's usually a list of people saying something
like "IQ is meaningless, it's a flawed concept (but my IQ is 138)". Are there
any people saying "I worked really hard at this, I spent a lot of time and
effort. I ranked 984th."?

Because I'd love to see the results if those smart people got together and
spent some serious time and effort on it.

Lots of popular science projects suffer from a heavy churn rate, which leads
to people being introduced to the subject, producing an introductory program,
doing a bit of reading, but then moving onto something else. A few people
stay, and work on intermediate and advanced level projects, but they suffer
from lack of interest and expertise. See, for example, all the millions of
artificial life / evolution softwares derived from Martin Gardners Bugs. (See
also the death of Fractint, which was excellent software but did not
transition to Linux or Windows or modern display programming.)

[1] Not the right word but I'm not sure what fits.

~~~
cpeterso
Netlix's movie rating prediction contest is a great example of smart teams
collaborating. As the contest progressed some teams would join forces forming
new hybrid algorithms.

~~~
tvorryn
Yeah. In this competition collaboration was discouraged. That does keep
politics/alliance building skills out of the equation at the cost of worse
overall final products.

------
scotty79
> Otherwise if the ant was just spawned sitting on my hill, the target border
> tile is determined using some complex calculation considering the ratio of
> own/enemy ants near that border position, the possible distance to enemy
> hills, how many ants are already on a mission to a near border tile and how
> long they do need to reach their desitnation... Oh, I'm kidding, it was
> random. Completely random. Like in target =
> area.border.get(turnRandom.nextInt(area.border.size()));

Nice pun targeted at over-thinking of things. If you try to take many things
into account without any concrete knowledge of how they influence outcome
you'll get random result. So you may just start with random and see if it's
good enough.

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memnips
Unfortunately the link appears to be temporarily dead. Luckily before you read
about his bot you should watch it play anyways!

Here are two replays of the same map. The first is played by average players
and the second is played by xathis (and other top bots).

Avg:
[http://aichallenge.org/visualizer.php?game=335973&user=8...](http://aichallenge.org/visualizer.php?game=335973&user=8180)
Top:
[http://aichallenge.org/visualizer.php?game=329760&user=4...](http://aichallenge.org/visualizer.php?game=329760&user=4513)

~~~
WildUtah
Note that every one of those "average" players finished in the top 10%.

It's a hard problem to write any kind of generally adequate player for. All
the good bots depend heavily on subtle properties of emergent behavior. Don't
let the simple explanations fool you.

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LearnYouALisp
The first lines seemed familiar:

<http://quotenil.com/Planet-Wars-Post-Mortem.html>

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tvorryn
Haha. It didn't say that before, because he hadn't officially won yet. It's
actually been propagated from Tron: <http://a1k0n.net/2010/03/04/google-ai-
postmortem.html>

~~~
a1k0n
I definitely had no intention of starting a tradition there. Haha.

~~~
tvorryn
You didn't do too badly this time yourself. 11th place. Looking at what he
did, do you see what you could do to improve your bot further?

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a1k0n
Sure, but as he concludes at the end, I didn't want to spend too much time on
it. My bot was fairly unique in that it used Monte Carlo methods rather than
deterministic minimax, and it got the job done without too much effort. I
wrote a forum post describing the basic approach here:
[http://forums.aichallenge.org/viewtopic.php?f=24&t=2044](http://forums.aichallenge.org/viewtopic.php?f=24&t=2044)

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tszming
No content inside (but ads)

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bhrgunatha
> bplaced.net Zugriff verweigert, Fehler 403. Sorry, access forbidden, error
> 403. Contact service provider

I think the hosting provider may have pulled the plug after a traffic surge.

Google cache

[http://webcache.googleusercontent.com/search?hl=en&q=cac...](http://webcache.googleusercontent.com/search?hl=en&q=cache%3Ahttp%3A%2F%2Fxathis.com%2Fposts%2Fai-
challenge-2011-ants.html&btnG=Search&pbx=1&oq=&aq=&aqi=&aql=&gs_sm=&gs_upl=)

