ABSTRACT
Most Japanese food demand studies have been based on official databases. One reason for this is that the official databases are quite informative (we think they are among the best in the world) and easy to access. Second, nonofficial data are difficult and expensive to collect. Non-official data are used to supplement official data only when necessary. Third, scanner data have become very popular. Many supermarkets, convenience stores, department stores, and other stores use scanners to read bar codes attached to commodities being sold. Scanner data provide point-of-purchase information about customer purchases. Data typically include the bar code, price, time of purchase, and even the customer's sex and approximate age (the latter two data are added by the salesclerk). However, scanner data are usually store secrets and are very difficult to access. 1 In the next section we will discuss the major official databases.
