Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Thomas Lumley
You asked earlier about nnclust: it does single-linkage rather than complete-linkage clustering, that is, it defines clusters so that each point in the cluster has a nearest neighbour in the cluster closer than the threshold distance. This produces much less circular clusters than complete-l

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Hans Ekbrand
On Wed, Apr 21, 2010 at 03:14:46PM +0200, Roger Bivand wrote: > On Wed, 21 Apr 2010, Hans Ekbrand wrote: [...] >> Well, hclust was useful, once I understood how cutree works. What >> would be the benefit of dnearneigh(), is it faster? >> > > For larger data sets, hclust needs a triangular distanc

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Roger Bivand
On Wed, 21 Apr 2010, Hans Ekbrand wrote: On Wed, Apr 21, 2010 at 01:42:05PM +0200, Roger Bivand wrote: So you do not want hclust at all, really. Look at dnearneigh() in spdep, setting a 100m bound. Then use n.comp.nb() to see which points belong to which graph component, using perhaps plot.nb w

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Hans Ekbrand
On Wed, Apr 21, 2010 at 01:42:05PM +0200, Roger Bivand wrote: > So you do not want hclust at all, really. Look at dnearneigh() in spdep, > setting a 100m bound. Then use n.comp.nb() to see which points belong to > which graph component, using perhaps plot.nb with colours to distinguish > the

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Roger Bivand
On Wed, 21 Apr 2010, Hans Ekbrand wrote: On Tue, Apr 20, 2010 at 11:13:22PM +0200, Hans Ekbrand wrote: Roger Bivand wrote: On Tue, 20 Apr 2010, Hans Ekbrand wrote: I have just read about clustering on wikipedia, and learnt that what I want is: Agglomerative hierarchical clustering, with com

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-21 Thread Hans Ekbrand
On Tue, Apr 20, 2010 at 11:13:22PM +0200, Hans Ekbrand wrote: > Roger Bivand wrote: > > On Tue, 20 Apr 2010, Hans Ekbrand wrote: > > > >> I have just read about clustering on wikipedia, and learnt that what I > >> want is: > >> > >> Agglomerative hierarchical clustering, with complete linkage > > >

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-20 Thread Hans Ekbrand
Roger Bivand wrote: > On Tue, 20 Apr 2010, Hans Ekbrand wrote: > >> I have just read about clustering on wikipedia, and learnt that what I >> want is: >> >> Agglomerative hierarchical clustering, with complete linkage > > library(cluster) > ?hclust > > is for clustering with moderate numbers of poi

Re: [R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-20 Thread Roger Bivand
On Tue, 20 Apr 2010, Hans Ekbrand wrote: I have just read about clustering on wikipedia, and learnt that what I want is: Agglomerative hierarchical clustering, with complete linkage library(cluster) ?hclust is for clustering with moderate numbers of points. Below: in UTM, the units are metr

[R-sig-Geo] complete linkage Agglomerative hierarchical clustering, nnclust, spatclus or something else?

2010-04-20 Thread Hans Ekbrand
I have just read about clustering on wikipedia, and learnt that what I want is: Agglomerative hierarchical clustering, with complete linkage I searched for suitable r-packages for this and found nnclust, and spatclus. Are those the packages that you could recommend for clustering events data (the