Miikkulainen

Miikkulainen (1996) trained a network to receive a sentence one word at a time, and then assign roles to nouns and verbs in an agent-action-patient triple. For example, the girl saw the boy got mapped into agent=girl, act=saw, patient=boy, represented as |girl saw boy|. His network was divided into three subnetworks: a parsing network, a segmenter network, and a stack network. The combination of these three network was able to divide input sentences in such a way as to allow it to correctly process sentences with higher levels of phrase embedding than ever seen during training. Once divided, phrases were assigned case-role representations. Each subnetwork was trained independent of the other and with no knowledge of what the relationship between the system's input and the system's output was (since none of the networks see both the outside inputs and outputs). The average unit error for the parser subnetwork was of 0.019. Center embedding greatly diminished the percentage of correctly remembered agents.

Because each subunit was trained independently of the others, the author mentioned that his system should be seen as a model for human performance rather than learning. He also mentions that "Other, more cognitively valid learning mechanisms may be possible", and suggested that such systems should be studied.

Back to the Table of Content

Back to the previous topic

To the next topic