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✦   LIBER   ✦

The demise of constant price impact functions and single-time step models of speculation

✍ Scribed by Damien Challet


Publisher
Elsevier Science
Year
2007
Tongue
English
Weight
169 KB
Volume
382
Category
Article
ISSN
0378-4371

No coin nor oath required. For personal study only.

✦ Synopsis


Constant and symmetric price impact functions, most commonly used in agent-based market modelling, are shown to give rise to paradoxical and inconsistent outcomes in the simplest case of arbitrage exploitation when open-hold-close actions are considered. The solution of the paradox lies in the non-constant nature of real-life price impact functions. A simple model that includes explicit position opening, holding, and closing is briefly introduced and its information ecology discussed, shedding new light on the relevance of the Minority Game to the study of financial markets.