Hi Arthur, this is the classical task of clustering/classification algorithms (like SVM, k-means, etc.)
For R take a look at the Cluster task page [1] for unsupervised classification, and Machine Learning [2] for some supervised methods. In Grass the classification/clustering methods are mostly directed to imagery data, and their objective is to classify spectral images [3] [4]. Anyway you could use it with other kind of imagery... You also could take a look to this Python/C project, quite easy to use, for supervised clasification: https://mlpy.fbk.eu/ And LIBSVM, which has various interfaces (Python, R, etc.): http://www.csie.ntu.edu.tw/~cjlin/libsvm/ Hope it helps, giovanni [1] http://cran.r-project.org/web/views/Cluster.html [2] http://cran.r-project.org/web/views/MachineLearning.html [3] http://grass.osgeo.org/grass64/manuals/html64_user/i.cluster.html [4] http://grass.osgeo.org/grass64/manuals/html64_user/i.maxlik.html Il 10 dicembre 2009 17.08, HINTERMEISTER, ARTHUR W. (Artie) <[email protected]> ha scritto: > Hello, > > > > I currently have a map that looks something like this: > > > > ----------------------------------------- > > | x x o x o x | > > | x x x x a o a | > > | a x o o x | > > | x x o o o a | > > | x x x o a o a o| > > | x x o x o x a a a | > > | x x o o a a a | > > ----------------------------------------- > > > > x = low risk > > o = moderate risk > > a = high risk > > > > Each letter represents a person, and the entire map represents a state. Each > person’s “risk score” is a continuous numeric value, but I have categorized > it into low, moderate, and high for visual simplicity. What I’m hoping to do > is draw lines that will divide out the categories. The lines do not have to > necessarily be straight, but I would like them to be simple enough. I figure > that I would have to account for any overlapping or outlying persons. This > is my initial idea of how the map would turn out: > > > > ----------------------------------------- > > | / / | > > | / / | > > | x / o / a | > > | / / | > > | / / | > > | / / | > > | / / | > > ----------------------------------------- > > > > I have downloaded and installed GRASS and R, but I am not sure what type of > spatial method or analysis to use. Could someone please offer me advice on > how to get started with this project? Thanks so much! > > > > > > ------------------------------------------------------ > > Arthur Hintermeister > > [email protected] > > > > > > _______________________________________________ > grass-stats mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/grass-stats > > _______________________________________________ grass-stats mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-stats
