[GRASSLIST:738] Re: Spatial Clustering or Network Problem?

[Hamish]

> I have an interesting problem and after spending some time looking
> through the clustering documentation in R, I'm not sure that is the
> right approach.
> 
> I have a region for which a series of bird surveys were conducted
> within a vector defined grid. The coverage is not complete and I want
> to assess how best to clump the grid squares based on a survey
> completeness. Thus some grid squares will have a had no survey and
> others will be partial and others will be complete. I want to group
> them irregularly so that I end up with groups of squares that have had
> n number of completed surveys conducted. 
> 
> When I first thought of this problem I thought of R and using some
> clustering mechanism, but it would appear to me that these are all
> based on the idea of grouping data based on similarity of value and
> specifying at the outset how many groups you will end up with at the
> end. My problem is the opposite in that I want to value for each group
> to be as close to each other as possible, but I don't know how many
> groups I will end up with.
> 
> Then I started wondering about turning the centroids of these squares
> into a network using v.delaunay and using a network approach
> to the problem, although I'm not sure how I might do this.

set the region resolution to match the vector grid size and run
s.cellstats from GRASS 5.4. Then clustering/r.neighbors etc in GRASS 6.

???

Hamish