Information theory

Fairthorne’s theory of notification is an elegant example of a theory in information science

Fairthorne’s theory of notification clarifies the foundations of information science. He defined ‘notification’ as ‘mention and delivery of recorded messages to users’, listing as the main elements of library operations: (1) Source (e.g., authors), (2) Code (e.g., language of a book), (3) Message (the signal), (4) Channel (e.g., microfilms), (5) Destination (e.g., reader) and (6) Designation (subject description).

Nitecki, Joseph Z. 1995. Philosophical Aspects of Library Information Science in Retrospect.

 


Variables

The scope of our activities and studies lie inside Discourse but outside Signaling, i.e., outside the scope of Shannon’s Information Theory. The variables involved are, in general terms, Source, Destination, Designation, and Message, Channel, Code. In the present context a Code is a symbol system used to indicate choices made from a set of Messages, and represented by patterns of physical events (signals or inscriptions) consistent with the physical mode and conditions of communication, the Channel, in the given social and physical environment.
Formally the Message set is adequately defined as an agreed finite set of distinct identifiable entities, from which choices are made by Sources. Here we regard it also as drawn from what can be told in a given recorded language. The Sources are those within the given environment who tell it, in the sense of being agreed and identifiable publishers, distributors, organizations, or accepted authors. The latter need not be actual authors. From the present point of view the works of Shakespeare, or of anonymous authors, are those records that tile local retrieval tools attribute to “Shakespeare,” or to “anon.” Tile Destinations are those within the given environment who are to be told, or wish to be told. They must be identifiable, but otherwise may be organizations, functionaries, groups, or individuals. A set of Designations is assigned to Messages, Sources, or Destinations to characterize them according to what is told, or is to be told. They are aspects of what the particular discourse is “about,” in some operational sense. For example, Subject Indexing assigns topics to the messages; author indexes may be classified by subject matter; Selective Dissemination of Information designates executives according to what they should be told about. Clearly the same set of Designations can be assigned differently according to circumstances. A reader (Destination) may well differ with the author (Source) as to the main interest (Designation) of an article (Message).

source: Morphology of “Information Flow” Robert A. Fairthorne. Journal of the ACM. Volume 14 , Issue 4 (October 1967)

[Photomedia Forum post by T.Neugebauer from Oct 12, 2007  ]