The persistence phenomenon is studied in a financial context by using a novel mapping of the time evolution of the values of shares in a portfolio onto Ising spins. The method is applied to historical data from the London Financial Times Stock Exchange 100 index (FTSE 100) over an arbitrarily...

The relaxational behaviour of the bond-diluted two-dimensional Ising model below the percolation threshold is studied using Monte Carlo techniques. The non-equilibrium decay of the magnetization, M(t), and the relaxation of the equilibrium spin-spin autocorrelation function, C(t), are monitored.