A Modern Approach to the Efficient-Market Hypothesis

Gabriel Frahm

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arXiv · 1302.3001

A Modern Approach to the Efficient-Market Hypothesis

Gabriel Frahm

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Abstract

Market efficiency at least requires the absence of weak arbitrage opportunities, but this is not sufficient to establish a situation where the market is sensitive, i.e., where it "fully reflects" or "rapidly adjusts to" some information flow including the evolution of asset prices. By contrast, No Weak Arbitrage together with market sensitivity is sufficient and necessary for a market to be informationally efficient.

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Gabriel Frahm. 2013-02-13. A Modern Approach to the Efficient-Market Hypothesis. https://arxiv.org/abs/1302.3001

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