The Bidirectional Communication Theory--A Generalization of Information Theory

A generalization of information theory is presented with the aim of distinguishing the direction of information flow for mutually coupled statistical systems. The bidirectional communication theory refers to two systems. Two directed transinformations are defined which are a measure of the statistical coupling between the systems. Their sum equals Shannon's transinformation. An information flow diagram explains the relation between the directed transinformations and the entropies of the sources. An extension to a group of such systems has also been proposed. The theory is able to describe the informational relationships between living beings and other multivariate complex systems as encountered in economy. An application example referring to group behavior with monkeys is given.