1. Memory, Representation and Abstraction
Recall Elman's
Simple Recurrent Network
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Trained on sequences of symbols
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Training was simply prediction
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Symbols represented various aspects of language
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phonemes
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letters
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words
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Found evidence that the network was detecting underlying patterns
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error levels indicated expectations of word boundaries
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cluster analysis found words that were used similarly had similar representations
Could this same, simple methodology be used in a non-symbolic world?
Yes, but the real world has some issues:
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Sometimes there are long stretches of very similar inputs
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Interesting events can be rare
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This creates a situation of "catastrophic forgetting"
1.1. The Human Network Experiments
1.2. What can be done about catastrophic forgetting?
Recall our goals BringingUpRobot
2. Governor For Neural Networks
Something like a Self-Organizing Map that sits between the environment and the network that automatically "balances" the categories of training data.
2.1. A Governor for a Feedforward Network
Categories [input] + [output]
2.2. A Governor for a SRN
Categories [input] + [context] + [output]
2.3. It works!
