In retail markets, competition among firms happens "locally". But what is the right way to define the local geographic market? Using a natural experiment involving petrol stations on Greek islands and in Athens, Christos Genakos and Themistoklis Kampouris show that the methodologies both researchers and competition authorities use to define local markets are, to put it bluntly, wrong.

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16 March 2026

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LSE Business Review

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https://blogs.lse.ac.uk/businessreview/2026/03/16/everything-you-thought-you-knew-about-local-markets-is-wrong/

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