

Using genetic algorithms to train a Mario AI - yayitswei
http://forums.tigsource.com/index.php?topic=15664.msg450842#msg450842

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feral
Reminds me of the AI competition on infinite mario, recently: Here is a video
of the winning bot (A* based approach), cool to watch, as they display its
trajectory calculations. <http://www.youtube.com/watch?v=DlkMs4ZHHr8>

GA is cool and everything, but I am sometimes sceptical about its merits. Yes,
it gives you a natural problem representation, but would it really have done a
better job in this particular domain than using a technique like simulated
annealing to move through the Mario AI parameter space?

We just don't know without seeing benchmark comparisons. Maybe its much worse.
So, its a cool application, but we should be cautious about how quickly we
decide GA was a particularly suitable search algorithm.

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mirkules
I think simulated annealing would fall short if the levels have a lot of dead
ends. A good reason to use GA is precisely to avoid the problem of getting
stuck in local minima/maxima.

(Direct link to mario ai website: <http://www.marioai.org/>)

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feral
Simulated annealing is also intended to avoid getting stuck in local maxima.
It sounds like you are mixing it up with some sort of greedy search.

Also, it sounds as if you think they are optimising Mario's position in the
level (when you talk about the level having dead ends). I haven't checked, but
I several doubt thats the case. I would bet they are optimising a control
scheme for mario, and that local maxima in the search space are locally good
sets of control parameters, rather than anything to do with the topology of
the level.

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andymorris
I would have really liked to have seen a video sample at various stages of the
evolution :-(

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TGJ
What program would I use to edit the code? Just notepad or is this specific to
another language?

