Abstract

This paper describes the package <b>PtProcess</b> which uses the <b>R</b> statistical language. The package provides a unified approach to fitting and simulating a wide variety of temporal point process or temporal marked point process models. The models are specified by an intensity function which is conditional on the history of the process. The user needs to provide routines for calculating the conditional intensity function. Then the package enables one to carry out maximum likelihood fitting, goodness of fit testing, simulation and comparison of models. The package includes the routines for the conditional intensity functions for a variety of standard point process models. The package is intended to simplify the fitting of point process models indexed by time in much the same way as generalized linear model programs have simplified the fitting of various linear models. The primary examples used in this paper are earthquake sequences but the package is intended to have a much wider applicability.

Highlights

  • This paper describes a unified approach to fitting and simulating a wide variety of temporal point process or temporal marked point process models using the R statistical language (R Development Core Team 2010)

  • These models are defined in terms of a conditional intensity function, i.e., conditional on the history of the process over time

  • An example of a ground intensity function is that of the simple ETAS model, i.e., epidemic type aftershock sequence model used in modelling earthquake counts, see Ogata (1988, 1998, 1999)

Read more

Summary

Introduction

This paper describes a unified approach to fitting and simulating a wide variety of temporal point process or temporal marked point process models using the R statistical language (R Development Core Team 2010). These models are defined in terms of a conditional intensity function, i.e., conditional on the history of the process over time. PtProcess: Modelling Marked Point Processes Indexed by Time in R aftershocks These characteristics can be observed in the upper panel of Figure 1.

Mathematical background
Ground intensity function
Likelihood function of simple model
Marked point process
Residual process
Model simulation
Increment τ for the next event simulation:
Overview of structure
Mark distributions
Model parameter space
Marked point process model object
Generic functions
Model fitting
Example
Null model
Full model
Goodness of fit
Simulation
Current development
Computational complexity
Spatial distribution as a mark
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call