PURPOSE: To attain stable and quick learning by learning only an initial state until the reduction of errors becomes less than a threshold in the case of extending a learning section in a past direction and learning it again, and then learning a weight value and a time constant also.
CONSTITUTION: At the time of judging that a learning section is extended in a time-retroactive direction, a learning section control part 41 outputs a control signal to a learning control part 54 and the control part 54 receiving the signal outputs a control signal to a most nose diving direction calculating part 47, a network parameter correction quantity calculating part 48 and a network parameter correcting part 49. Immediately after extending the learning section in the time-retroactive direction, a convergence deciding part 46 decides an error at each time sent from a reverse propagation error calculating part 45 and the control part 41 learns only the initial state by the use of the extended time-sequential data without updating an already learned weight value and a time constant until the quantity of error reduction becomes less than a threshold. After its reduction less than the threshold, the control part 41 learns the weight value and the time constant in addition to the initial state.
KARAKI TAKESHI
KITAGAWA YUMIKO
HITACHI TOHOKU SOFTWARE