Information-Theoretic Approach to Financial Market Modelling

Eckhard Platen

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arXiv · 2602.14575

Information-Theoretic Approach to Financial Market Modelling

Eckhard Platen

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Abstract

The paper treats the financial market as a communication system, using four information-theoretic assumptions to derive an idealized model with only one parameter. State variables are scalar stationary diffusions. The model minimizes the surprisal of the market and the Kullback-Leibler divergence between the benchmark-neutral pricing measure and the real-world probability measure. The state variables, their sums, and the growth optimal portfolio of the stocks evolve as squared radial Ornstein-Uhlenbeck processes in respective activity times.

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Eckhard Platen. 2026-02-16. Information-Theoretic Approach to Financial Market Modelling. https://arxiv.org/abs/2602.14575

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