Definition

Noun: - (Communication Theory): A numerical measure quantifying the uncertainty or randomness associated with a specific outcome or event within a system. It represents the amount of data or the degree of surprise conveyed when a particular outcome occurs from a set of possibilities.

Usage

This term is a technical concept primarily used in fields like communication theory, information theory, and computer science. It refers to the fundamental, measurable quantity of information. - The selective information of a fair coin flip is exactly one bit. - In this encoding scheme, more probable symbols carry less selective information.

Advanced Usage

• In Mathematical Contexts: Often synonymous with "information content" or "self-information". It is calculated as the negative logarithm of the probability of a given event. A less probable event yields a higher value of selective information.
  • The selective information of a rare alarm signal is much greater than that of a routine status update.

Variants and Related Words

• Information (n): A broader, more general term for knowledge or data communicated. "Selective information" is a specific, technical subset of this concept.
• Bit (n): The fundamental unit of selective information when logarithms are base 2.
• Entropy (n): The average or expected value of selective information across all possible outcomes of a random variable.

Synonyms

• Information content
• Self-information
• Surprisal (in some technical contexts)

Related Phrases

• Measure of information: A phrase describing the function of selective information.
• Information theory: The field of study where this concept is central.

Noun

1. (communication theory) a numerical measure of the uncertainty of an outcome
   • the signal contained thousands of bits of information