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Pretty pictures and diagrams

von Stengel, Bernhard ORCID: 0000-0002-3488-8322 (2014) Pretty pictures and diagrams. LSE Research Festival 2014, The London School of Economics and Political Science. (Submitted)

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This is a new film which presents a slideshow on ‘Pretty Pictures and Diagrams’, or PPAD, which is actually a technical acronym for ‘Polynomial Parity Argument with Direction’. This ‘parity argument’ says that a path that starts somewhere and does not branch must end somewhere, so it has a pair of endpoints. The path represents a computation path that finds an equilibrium in an economic model. The film shows, in pictures, how such a path-following method works: A knight can find his princess in a castle if each room has only one door. An abstract scenario of ‘triangle partitions’ that are connected by following a path of ‘triangle flipping’ via ‘butterflies’ is then considered. However, these paths can be exponentially long. Hence, path-following is sometimes impractical, and we need research into other methods for finding an economic equilibrium.

Item Type: Audio/visual resource
Official URL:
Additional Information: © 2014 The Author
Divisions: Mathematics
Subjects: Q Science > QA Mathematics
Date Deposited: 15 Jul 2014 15:10
Last Modified: 01 Nov 2021 00:19
Projects: LSE Research Festival 2014

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