External or internal shocks may lead to the collapse of a system consisting of many agents. If the shock hits only one agent initially and causes it to fail, this can induce a cascade of failures among neighoring agents. Several critical constellations determine whether this cascade remains...

In this paper we focus on diversity-induced resonance, which was recently found in bistable, excitable and other physical systems. We study the appearance of this phenomenon in a purely economic model of cooperating and defecting agents. Agent's contribution to a public good is seen as a social...

We analyse time series of CDS spreads for a set of major US and European institutions on a period overlapping the recent financial crisis. We extend the existing methodology of drawdowns to the one of joint drawups, in order to estimate the conditional probabilities of abrupt co-movements among...