PURPOSE: To improve processing speed by normalizing the price or the time in a market price patterning means for the change of the market price in the past, and classifying the market price in the future by a neuro-computer.

CONSTITUTION: A market price classifying device is composed of a market price patterning means 21 and a neuro-computer 22 and the market price patterning means 21 has either a price normalizing function or a time normalizing function or has the both functions. By inputting the value of the market price in the past to the market price patterning means 21, the market price patterning means 21 patterns the change of the market price. The pattern of the market price change in the past is classified to various categories by the neuro-computer 22 and outputted. Since the neuro-computer 22 can execute parallel processing, the change of the market price can be forecasted in a short time.