2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/208885We study investment strategy in different models of financial markets, where the investors cannot reach a perfect knowledge about available assets. The investor spends a certain effort to get information; this allows him to better choose the investment strategy, and puts a selective pressure upon assets. The best strategy is then a compromise between diversification and effort to get information.10 pages, 5 figuresDisordered Systems and Neural NetworksPortfolio Managementtext