"**complexity**, *n.* Add: **[2.] c.** *Math.* More fully ** computational complexity**. A measure of the difficulty of solving a class of problem, as measured by the expected number of computational steps required to do so using an algorithm; the branch of computational theory concerned with this property."

- Definition of Complexity Theory

"Critically interacting components self-organize to form potentially evolving structures exhibiting a hierarchy of emergent system properties."

- What is complexity?

- What Is Complexity?

- What is Complexity Theory?

- Cogprints - What is Complexity? - The philosophy of complexity per se with application to some examples in evolution

"That property of a language expression which makes it difficult to formulate its overall behaviour even when given almost complete information about its atomic components and their inter-relations."

- What is Complexity? - The philosophy of complexity per se with application to some examples in evolution. (Title Page)

- What is Complexity ?

"1. Complexity is a measure of variety of states in the system. (Ashby, 1973; Beer, 1970).2. Complexity is being marked by an involvement of many parts, aspects, details, notions, and necessitating earnest study or examination to understand or cope with (Webster's Third International Dictionary; Klir, 1985).

3. Complexity has many varied interrelated parts, patterns, or elements and consequently is hard to understand fully (Klir, 1985).

4. Complexity is the lack of connectedness in the system (Casti, 1992).

5. "In general, we seem to associate complexity with anything we find difficult to understand." (Flood and Carson, 1993).

6. Complexity is a perceived systems attribute which increases as the number and variety of elements and relationships within the system becomes greater, and increases as the level of predictability and understanding of the system as a whole decreases (McCarthy, 1995)."

- What is Complexity? (Revisited)

- GELL-MANN, Murray, What is Complexity?

Gell-Mann (1995)

- PHELAN, Steven E., What is complexity science,
*really*?

- MIELE, Frank, Skeptics Society--Newsworthy

- Complexity International
- computational complexity (CC)
- Complexity Digest
- Complexity
- Journal of Complexity
- CC computational complexity
- Complexity in Human Systems

- Complexity On-line
- ECCC - The Electronic Colloquium on Computational Complexity
- The Complexity and Artificial Life Research Concept for Self-Organizing Systems
- Complexity, Self Adaptive Complex Systems, and Chaos Theory
- The Complexity Zoo
- Hypertext Bibliography of Measures of Complexity
- Average-Case Complexity Forum
- Complexity People
- My Computational Complexity Web Log
- Exploratorium's Complexity Web Site
- Complexity of Cooperation, Robert Axelrod
- Algorithms and Complexity
- Information-Based Complexity
- VCU Complexity Research Group
- Computability and Complexity in Analysis - Network

- BARNETT, William A., Alfredo MEDIO and Apostolos SERLETIS, Nonlinear and Complex Dynamics in Economics

- BROCK, William A. and Pedro J. F. de LIMA, Nonlinear Time Series, Complexity Theory, and Finance

Brock and de Lima (1995)

Skeptics Society: A Quick & Dirty Guide To Chaos And Complexity Theory

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