I study the limit of a large random economy, in the ideal case of perfect competition, where full information is available to all market participants, and where a set of consumers invests in financial instruments engineered by banks in order to optimize their future consumption. This provides a...

By analysing a large data set of daily returns with the maximum likelihood data clustering technique, we identify economic sectors as clusters of assets with a similar economic dynamics. The sector size distribution follows Zipf's law. Secondly, we find that patterns of daily market-wide...