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I am indebted to numerous programmers with greater skills who have been kind enough to post open-source code. Over the years, I have found myself writing various conversion programs and batch processors that have helped me automate tasks. I am posting the code (or links to the code) here to make these tools available to others who might find them useful.

ArcView and ArcGIS tools:

    FragStatsBatch for ArcGIS 8    

    FragStatsBatch for ArcGIS 9

This program is designed for use with FragStats when users have a large landscape but are only interested in getting FragStats metrics for certain regions within the landscape. These regions are defined by points, lines, or polygons that are buffered by this program. Users should create a map in ArcGIS that includes a landscape raster and a shapefile containing unbuffered features. This program cycles through all of the features in the shapefile, buffers the features, and creates a smaller landscape file consisting of the buffered feature and a border (with negative values) that extends beyond the edge of the buffered feature. The program then calls FragStats via command line control. The program continues until FragStats has run for all of the buffered features.  There are now versions for ArcGIS 8 and 9, and the newer version (March 2005) adds the feature ID (FID) and feature name to the FragStats output.  Also note that Kevin McGarigal is hoping to incorporate this functionality into future releases of FragStats (current release is 3.3).

    Locate II to Shapefile Converter for ArcView 3.x

    Locate II to Shapefile Converter for ArcGIS

These scripts use output from the radio telemetry triangulation program Locate II that has been processed using gis.exe (gis.exe is included in the Locate II download). The script converts the Locate II output into shapefiles containing location error ellipses and location coordinates. Locate II and gis.exe are freeware.  Locate III (also free for desktop computers; a Palm version is for sale) has recently been released.  Locate III does not currently export error ellipses to shapefiles, but it can produce a file that can be used with gis.exe.  

    Calhome to ArcView 3.x Converter

    Calhome to ArcView 3.x Batch Converter

These avenue scripts for ArcView GIS 3.x accept one or more output files from program Calhome and convert the files into shapefiles. Calhome is a shareware program used for computing home ranges of animals based on location data.  Please note that I do not endorse the use of Calhome for home ranges.  For a variety of reasons, I feel that fixed kernel home ranges are the best tool currently available for calculating animal home ranges, and Calhome does not include a fixed kernel option.  If you are interested in freeware software that calculates fixed kernel home ranges, try KernelHR or Home Ranger, or the Home Range Extension.  I do not recommend Biotas or Animal Movement Extension at this time; versions of these 2 packages that I tested in late 2003 produced results that differed from each other and the other packages (see article here).

Model Averaging and Model Selection tools:

Model Averaging Spreadsheet (updated 11/2008)

I developed this spreadsheet for my course on the analysis of natural resources data, a seminar I taught in the spring of 2005 to introduce graduate students to model selection and multi-model inference.  This spreadsheet includes pages for model selection, predictor averaging, and response averaging.  A good familiarity with Ken Burnham and David Anderson's approach to model averaging and model selection is essential to understanding how to use this spreadsheet properly!

The November 2008 update includes an updated response averaging ("Model Average Y") page that will model average response variables after applying a number of common link functions (e.g., logistic link). It also includes a "Scenarios" page that will quickly calculate the model-averaged response for a large number of scenarios (combinations of predictor variables).




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