Extreme events are defined as extreme high (or low) values of whatever statistics of the output of the system we are interested in. These values play an important role because they may correspond to abnormal or dangerous operating conditions. Classical statistical inference techniques provide a good description of central behaviour, but not of extreme events. This was our motivation for resorti...

We introduce a statistical agent based model to describe the phenomenon of drug abuse and its dynamical evolution at the individual and global level. The agents are heterogeneous with respect to their intrinsic inclination to drugs, to their budget attitude and social environment. The various levels of drug use were inspired by the professional description of the phenomenon and this permits a d...

Nanoscale electronic devices like field-effect transistors have long promised to provide sensitive, label-free detection of biomolecules. In particular, single-walled carbon nanotubes have the requisite sensitivity to detect single molecule events and sufficient bandwidth to directly monitor single molecule dynamics in real time. Recent measurements have demonstrated this premise by monitoring ...

instituto universitario de lisboa abstract Despite the accumulated evidence that retention is an ineffective and potentially harmful remedial strategy, several countries struggle with high levels of retention in compulsory schooling. This article provides evidence of the impact of the Portuguese national educational policy “Programa Mais Sucesso Escolar” (PMSE) using class size, class compositi...

This paper shows that rare events help explaining the cross section of asset returns, the reason being that they are important in shaping agents’expectations. I reconsider the "bad beta, good beta" ICAPM proposed by Campbell and Vuolteenaho and I point out that the explanatory power of the model depends on including the stock market crash that opened the Great Depression. When using a Markov-sw...

A common assumption in frequency analysis is that hydrologic extremes ( oods or heavy precipitation) are generated by a random process. This implies that natural climatic variability does not change the distribution of extreme events. A regional frequency analysis approach is proposed to test the hypothesis of randomness over secular time scales. Observed regional occurrences of extreme events ...

A criminologist has been using national self-report surveys to estimate the incidence of self-defense gun use in the United States (Kleck 199 I). His most recent estimate is that civilians use guns in self-defense against offenders more than 2.5 million times each year (Kleck and Gertz 1995). This figure has been widely cited, not only by the National Rifle Association but in the media and in C...

, R. Ardito , C. Arnaboldi , D. R. Artusa , F. T. Avignone III , M. Balata , , M. Barucci , J. Beeman , C. Brofferio , C. Bucci , S. Capelli , F. Capozzi , , S. Cebrian , O. Cremonesi , R. J. Creswick , M. Dolinski , A. de Waard , ,F. Ferroni , E. Fiorini , G. Frossati , C. Gargiulo , A. Giuliani , E. Guardincerri , , E. E. Haller , I. G. Irastorza , E. Longo , G. Maier , R. Maruyama , , S. Mor...

The economic idea behind the model is that the tails of the Gaussian distribution are too thin to model the credit market accurately. Although the Gaussian distribution is widely used in other asset classes, it is rarely suitable for extreme out-of-the-money options. But almost all credit default events are extreme events which are controlled by the tail of the distribution. For this reason we ...

The notion that natural disasters can be controlled is, of course, farcical; history is permeated with examples of countless failed attempts at this pointless task; it is synonymous with trying to build a perpetual motion machine. Nonetheless, there are ways to reduce their impact on human communities, particularly by looking away from the normal hypothesis. In a press conference on the remnant...