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Neat disconnected

Open chill0chill opened this issue 6 years ago • 3 comments

Hi, I am running a NEAT with more than 28 features and comparing it with a deep backprop network. I am running a regression problem.After running multiple configurations(pop size, crossover, mutation rate, connection add rate , etc). I am observing that neat is leaving out important features from the network if initial state is unconnected. If i start with fully connected network , then the accuracy is dropping a lot. Not to mention both the methods are underperforming deep fully connected network. Has anybody else faced this issue or does anybody has a thought on this problem?

chill0chill avatar Apr 09 '19 11:04 chill0chill

I did some thinking about this a while back, but I didn't implement it, so take that into consideration:

It might be beneficial to create a fitness function that rewards both objective score and smaller numbers of connections and/or hidden neurons. So if two different networks perform the same at the objective task, the smaller of the two networks would get a higher fitness score than the other. This would create a selection pressure towards smaller networks, which might make the solution space exploration more efficient (assuming the task can in fact be solved by a small network).

In your case you might also want to try starting with partially (randomly) connected initial states, not just fully connected and fully disconnected.

mathiasose avatar Apr 10 '19 09:04 mathiasose

Hi, I am running a NEAT with more than 28 features and comparing it with a deep backprop network. I am running a regression problem.After running multiple configurations(pop size, crossover, mutation rate, connection add rate , etc). I am observing that neat is leaving out important features from the network if initial state is unconnected. If i start with fully connected network , then the accuracy is dropping a lot. Not to mention both the methods are underperforming deep fully connected network. Has anybody else faced this issue or does anybody has a thought on this problem?

Do you ever found any solution to this problem ? i also running regression problem with 22 features and just noticed that most features doesnt even make it to the output node.

winatawelly avatar Aug 19 '19 00:08 winatawelly

I'm not sure what you mean by "disconnected" and "most features doesn't even make it to the output node", but it sounds like you may be impacted by the issue I filed just now: #255.

ntraft avatar Nov 20 '22 02:11 ntraft