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Layout of Autoassociative Networks

An autoassociative network in SNNS consists of two layers: A layer of world units and a layer of learning units. The representation on the world units indicates the information coming into the network from the outside world. The representation on the learning units represents the network's current interpretation of the incoming information. This interpretation is determined partially by the input and partially by the network's prior learning.

Figure gif shows a simple example network. Each unit in the world layer sends input to exactly one unit in the learning layer. The connected pair of units corresponds to a single node in the typical representation of autoassociative networks. The link from the world unit always has a weight of 1.0, and is unidirectional from the world unit to the learning unit. The learning units are fully interconnected with each other.

Figure: A simple Autoassociative Memory Network

The links between the learning units change according to the selected learning rule to fit the representation on the world units. The links between the world units and their corresponding learning units are not affected by learning.
Tue Nov 28 10:30:44 MET 1995