Information output system, information output method, and computer product

摘要

An output-history storing unit stores product information output to a terminal device as output history for each terminal device. A purchasing-history storing unit stores purchase information for identifying a product purchased by a user as purchasing history for each user. A verifying unit collates the output history stored in the output-history storing unit with the purchasing history stored in the purchasing-history storing unit, and verifies an effect of the product information.