Cover illustration

December 27, 2005; 102 (52)
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Cover image: Figure representing the number of economic entities that grow (or shrink) by a given amount. The probability density function has an exponential form in the center and a power-law behavior in the tails. The same shape appears to hold for all levels of aggregation of the economy, from products to national economies. See the article by Fu et al. on pages 18801–18806. Image courtesy of Nicola Nottoli, Fabio Pammolli, and Massimo Riccaboni.

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December 27, 2005; 102 (52)
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