Wednesday, November 6, 2013

AIWorld6: Stagnant worlds

The most common error of the previous AIWorlds were what I call 'stagnation'. Essentially, agents stop choosing to move, attack, replicate, or really do anything. The population just sits there. Every one of them.

AIWorld6 seemed to be an exception. Initially, worlds would run for >10M iterations and would stay lively. And then I found a bug. Specifically, the mutation rate was being set to 0 for a large percentage of the population. The recent evolution of predator/prey relationships was made with a world that started with the error and then the error was corrected to allow mutation again.

After correcting the error, I'm seeing stagnant worlds every time when I set the mutation rate to 0.01. Just now I tried setting the mutation rate to 0.001 and that world lasted 10M iterations.

It's clearly time to test this and find more about how and why the mutation rate affects the world's stagnation.

1 comment:

  1. I suspect that what you're experiencing is just the emergent behavior of a non-aging population optimizing it's survival in a world with infinite resources.

    I noticed you mention aging in another post, but I believe allowing the engine to kill an agent after it has been alive for a certain amount of time might help with this by incrementing a counter each step that the agent is alive, and killing them based on a lifespan variable. (There are multiple ways to do this such as a fixed life span or one that is a result of the average energy since birth)

    Further, by allowing resources to be depleted and replenished agents might evolve roaming behaviors, which might also mitigate your previous problem of sustainable life not being able to evolve if there wasn't an abundance of space.