- © 2013 by the Seismological Society of America
Online Material: Program manual, source code, and associated files.
The Southern California Earthquake Center (SCEC) Transient Detection intercomparison required that all participants apply their methods to the same datasets, each dataset containing some tectonic signal (or none), plus realistic noise. One way to produce these would be to add tectonic signals to actual data from the California continuous GPS network (CCGPSN), but there are two problems with this: using the same background series for all datasets makes it easy to isolate signals by differencing, and we would not know if there was a transient already present in the data. Instead, fully synthetic datasets were used, each of which had a different realization of the noise added to a different signal known only to the creator of the dataset. The Fakenet package was written to provide software for creating these datasets.
In developing Fakenet, the goals were to be able to:
Replicate, at least approximately, the observed statistical properties of Global Positioning Systems (GPS) data.
Create multiple realizations, with different non‐tectonic fluctuations. Testing a detection algorithm can then be done by examining its success or failure for datasets with the same signal but different versions of the noise.
Allow a wide range of source locations, types, and time histories.
Provide a log file to document the inputs for a particular simulation. This is useful for debugging, but more importantly it provides complete reproducibility (Mesirov, 2010; Lees, 2012): given the information in the log file, we can rerun the code to get the same results.
This paper describes the procedures used in this package, as well as outlining its structure. A user’s manual is available in the electronic supplement to this paper. It describes the details of operation, installation procedures, and the file formats. The supplement also includes the software itself, …