The Ghost in the Model

From here you can download the software used in the paper presented at the First conference of the European Social Simulation Association, and submitted to the Journal of Artificial Societies and Social Simulation. A local version of the conference paper is available if you cannot access it through the ESSA-1 website.

In the paper, we analyse a problem we had in FEARLUS with floating point arithmetic, finding that converting to interval arithmetic allows us to detect and warn when there is an issue instead of continuing on regardless into a situation in which the model gets into an invalid state. We also show that making some simple modifications to the Artificial Stock Market changes the output. Interval arithmetic has since proved less effective at dealing with the problems in the ASM than it did in FEARLUS.

The software is released under the GNU General Public Licence. Clicking any of the source download links will be taken as an assertion that you agree to abide by the terms of this licence.

The software is designed to work on a Sun Solaris platform, and should, but may not work on other Unix platforms. Versions for Intel Cygwin are provided where available. Swarm version 2.1.1 is used for FEARLUS on a PC, whilst the testing version dated 2001-12-18 has been used on a Solaris platform for FEARLUS and ASM-2.2.1. ASM-2.4 has been compiled successfully on an XP PC running Swarm 2.2 prerelease 10.

PackageDescriptionSun SolarisIntel CygwinParameters
FEARLUS 0-7A version of FEARLUS model 0-6-4 that uses interval arithmetic instead of floating point.downloaddownloaddownload
FEARLUS 0-6-2The version of the FEARLUS model that creates ghost agents due to floating point errors for certain parameters that are not exactly representable in double precision floating point arithmetic.downloadUse the Sun version.
ASM 2.2.1-fpThree versions of the Artificial Stock Market (version 2.2.1) converted for use in the conference paper.downloadDoes not work on Cygwin.Included in source tarball.
ASM 2.2.1-iThe Artificial Stock Market (version 2.2.1) converted for use with interval arithmetic.downloadDoes not work on Cygwin.download
ASM 2.4-fpThree versions of the Artificial Stock Market (version 2.4) converted for use in the JASSS paper.Use the Cygwin version (with an appropriate version of Swarm)downloadIncluded in source tarball.
lu1lu2sequence.cA short program to implement a check of sequences of Land Uses applied by a particular kind of agent as discussed in the papers.downloadUse the Sun version.Not applicable

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Software downloaded  model0-7  model0-6-2  ASM 2.2.1-fp  ASM 2.2.1-i  ASM 2.4-fp
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