Wednesday, April 10, 2019

Stochasticity, Randomness, and Chaos (and the differences between them)

In popular culture, words like "stochastic", "random", and "chaotic" are often used interchangeably. However, these three terms have totally different meanings. Furthermore, "randomness" and "chaos" are near opposites. Whereas "randomness" is used to simplify the process of model building, "chaos" is a phenomena that comes out of non-random models. Chaotic patterns appear random but are products of entirely deterministic processes. Chaos is an extreme sensitivity to initial conditions that relates to trajectories from deterministic systems gaining more and more individuality over time, as opposed to less. If it is chaotic, it is not random.

I explain the similarities and differences between stochasticity, randomness, and chaos in this two-part lecture recorded as a complement to material in my SOS 212 (Systems, Dynamics, and Sustainability) course at Arizona State University.

Lecture G1: Randomness and Chaos (SOS 212, Systems Dynamics and Sustainability, ASU)

  • Part 1: Randomness

  • Part 2: Chaos

For related videos that may be of interest, see my SOS 212 YouTube playlist.

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