Concepts of an Estimation System, an Adaptive System, and a Network of Adaptive Estimation Systems

A clear distinction is made between two concepts. One concept is called an estimation system and the other an adaptive system. Using these two concepts as building blocks and a Bayes minimum conditional risk approach, it is possible to give meaning to the concept of a network of adaptive estimation systems. Under the framework of the approach, unsupervised estimation (estimation without a teacher) is a classical statistical problem as is supervised estimation. Also, supervised estimation is a degenerate case of estimation and a special case of adapting. In general, adapting without a teacher is impossible.