title: Numerical simulations and the problem of periodicity in the cratering record.
abstract: Ages of craters in the record of impacts on earth may be uniformly period, totally random, or a mixture of the two.  These alternatives are studied through numerical simulation wherein time-series analysis is performed on real and simulated sequences to which random noise has been added to represent age-dating uncertainty.  We conclude that the real record is most likely to have been generated by a mixture of random and periodic impacts, with the random events constituting the majority.
authors.affiliation: Department of Geophysical Sciences, University of Chicago, IL 60637, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Trefil
authors.forename: D M
authors.initials: DM
authors.lastname: Raup
mesh_terms: D005075:Biological Evolution; D003198:Computer Simulation; D018534:Earth, Planet; D005580:Fossils; D005844:Geology / Q000706:statistics & numerical data; D019110:Meteoroids; D018543:Minor Planets; D015233:Models, Statistical; D010163:Paleontology / Q000706:statistics & numerical data*; D010507:Periodicity