Stochastic Epidemic Type Model for Analyzing Seismic Activity

In statistical seismology, we can use stochastic process to explain random natural phenomena. One area of study in stochastic processes is point process. At a point process, earthquakes are viewed as a collection of random points in a space, where each point represents the time or/and location of an earthquake. In stochastic epidemic type model earthquake occurrence is assumed as an epidemic, i.e. a large earthquake triggers aftershocks at a certain time interval and the impact may extend to a region. By using point process approach, a stochastic model can be presented with its conditional intensity function, that is the probability of earthquake occurrence per time unit. It is expected that the analysis on the conditional intensity function of the epidemic type model provides information about the probability of earthquake occurrence based on its history. We apply the model to analyze seismic activity in Java Island, Indonesia.