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Please see the request below, which I am forwarding from my son. He is a Forest Service research ecologist who is also moving into areas that will include human, as well as invasive species,  network analysis.  He is in the process of becoming a member of INSA, but also has grant and data analysis deadlines to meet.  Please feel free to copy him on any responses, and I will copy him on any general responses to the list serve.  Thanks. Bob Trotter


Greetings!  I'm hoping members of the SOCNET listserve might be able to send me in the right direction, as I am new to network analyses.  My research is focused on identifying and evaluating patterns of spread for invasive species (mostly insects) across the landscape, a process that is essentially a spatially based network study.  Currently, I am attempting to do something that is probably quite simple, but being new to the network software available, I'm hoping to get some suggestions for the best software to use for the following data parameters.

Essentially, I would like to determine the pattern of spread between nodes (which in this case are centroids in counties in the eastern U.S.), using the following assumptions.

1) The first node (county) with the invasive species is known.
2) The species can move to new nodes (counties), only if the counties share a physical border, I have a nodelist/adjacency matrix with this information.
3) A new node (county) is infested following the infestation of a neighboring node (county).
4) If two neighbors are infested at the same time, the source of infestation will be the closest county centroid, such that nodes (counties) are only infested by a single source.

Which network programs would you recommend to create an appropriate data set to analyze, and to visualize, this process.

If there are software packages out there that can animate this process, that would be even better.  Many thanks!

R Talbot Trotter III, Ph.D.
Research Ecologist
Northern Research Station
USDA Forest Service

Associate Research Scientist
Yale School of Forestry and Environmental Studies
New Haven, CT

Phone: 203-432-3978
Mobile: 928-380-6812
Fax: 203-230-4315
[log in to unmask]<mailto:[log in to unmask]>
51 Mill Pond Road, Hamden CT 06514

Robert T. Trotter, II Ph.D.
Regents' Professor and Chair
Department of Anthropology
Room 101G
575 East Pine Knoll Drive
Northern Arizona University
Flagstaff, AZ 86011
Email: [log in to unmask]<mailto:[log in to unmask]>
Phone: 928-523-4521
Mobile: 928-380-8684
Fax: 928-523-9135

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