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Topology of correlation based minimal spanning trees in real and model markets

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 نشر من قبل Guido Caldarelli
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Giovanni Bonanno




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We present here a topological characterization of the minimal spanning tree that can be obtained by considering the price return correlations of stocks traded in a financial market. We compare the minimal spanning tree obtained from a large group of stocks traded at the New York Stock Exchange during a 12-year trading period with the one obtained from surrogated data simulated by using simple market models. We find that the empirical tree has features of a complex network that cannot be reproduced, even as a first approximation, by a random market model and by the one-factor model.



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