To statistically process data in time of purchase including taste of a purchaser about various high-quality brand commodities to provide prediction decision material when performing recognition of a marketability position and drafting in a production plan from the data in time of the purchase including the taste of the purchaser about the various top brand commodities such as a bag, a watch or an automobile.

This prediction device is provided with: a means for reading time series data of the purchase of a same type or similar commodity group; a means performing ordering from the time series data in the commodity; and a means setting the commodity group of brands of x, y, z as an upper shift system therefrom, producing a transition matrix of an upper triangle matrix from x, xb (whrein, x shows the present purchase; and xb shows the previous purchase) if x is the brand commodity positioned in a topmost rank, that y is the brand commodity positioned in the next rank, and that z is the bottommost brand commodity, and deciding the marketability position, and the production plan or the like of the brand articles.