Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!umich!samsung!brutus.cs.uiuc.edu!psuvax1!psuvm!auvm!WATDCS!U5GE91MA From: u5ge91ma@WATDCS.UWATERLOO.CA (Graham Dudley) Newsgroups: bit.listserv.gis-l Subject: Cluster analysis and GIS Message-ID: Date: 7 Feb 90 11:19:25 GMT Sender: Geographic Information Systems Discussion List Reply-To: Geographic Information Systems Discussion List Lines: 23 Approved: NETNEWS@AUVM Gateway At this point, the object is to use an agglomerative cluster analysis as a possible way to address the modifiable areal unit problem. As such, the objects to be clustered would be either points or small areas (e.g., census enumeration areas). Currently, I use SAS to perform the cluster analysis and then use a micro-based mapping package to present the results (this is being done in an exploratory way using census tracts as the basic statistical unit). I realize that the mapping of areal information can be done using SASGRAPH but I find this rather inflexible. I also would like to tried SYSTAT on the MAC but my version (3.2) does not allow for the importing of boundary files (contrary to what the manual says). Ideally, I would like to be able to view interactively what is happening spatially as the observations are agglomerated into fewer and fewer clusters (i.e., as the level of resolution decreases). I would also, at some point, like to apply this idea with a raster-based system as an alternative approach to performing overlay operations. ..graham -------- Graham Dudley BITNET: U5GE91MA@WATDCS.UWaterloo.ca Department of Geography CONNECT: DUDLEYG University of Waterloo Waterloo, Ontario, Canada N2L 3G1