1. An information processing apparatus learning a preference of a user for a content item, the apparatus comprising: acquiring means for acquiring an operation or expression of the user for a certain content item as feedback information; training data generating means for generating training data for the preference learning from the feedback information acquired by the acquiring means; and learning means for learning the preference of the user and how to attach a meaning to the feedback information in association with the training data by using multiple pieces of training data generated by the training data generating means.