title: Universal behavior of the interoccurrence times between losses in financial markets: independence of the time resolution.
abstract: We consider representative financial records (stocks and indices) on time scales between one minute and one day, as well as historical monthly data sets, and show that the distribution P(Q)(r) of the interoccurrence times r between losses below a negative threshold -Q, for fixed mean interoccurrence times R(Q) in multiples of the corresponding time resolutions, can be described on all time scales by the same q exponentials, P(Q)(r)∝1/{[1+(q-1)βr](1/(q-1))}. We propose that the asset- and time-scale-independent analytic form of P(Q)(r) can be regarded as an additional stylized fact of the financial markets and represents a nontrivial test for market models. We analyze the distribution P(Q)(r) as well as the autocorrelation C(Q)(s) of the interoccurrence times for three market models: (i) multiplicative random cascades, (ii) multifractal random walks, and (iii) the generalized autoregressive conditional heteroskedasticity [GARCH(1,1)] model. We find that only one of the considered models, the multifractal random walk model, approximately reproduces the q-exponential form of P(Q)(r) and the power-law decay of C(Q)(s).
authors.affiliation: Institut für Theoretische Physik, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany.
authors.forename: Josef
authors.initials: J
authors.lastname: Ludescher
authors.affiliation: Institut für Theoretische Physik, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany.
authors.forename: Armin
authors.initials: A
authors.lastname: Bunde