OUTLINE OF BASIC MODELS

The perceptron is a “single-layer” neural net. It has a convergence theorem proving that any task that it can do can be learned by it. It was early pointed out that it has formal limits eg exclusive disjunction.

Hopfield nets use the metaphor of a spin glass from physics. 

Example of Hopfield Network

Network consists of400 Neurons (-1+) 1

Each -1 is represented by a white pixel Each +1 is represented by a black pixel

20 patterns are stored according to storage equation

1. ill-suited for storage of correlated patterns

Note :: Hopfield network is less than optimal in Some respects.

Nonetheless still of great conceptual significance since it constitutes a fully connected NN for which many questions can be given an analytical answer .