Great thanks it worked a treat; a lot of time in R being pointed to the correct package / function is all that is needed.
Chris -----Original Message----- From: Roger Bivand [mailto:[email protected]] Sent: 01 July 2013 12:12 To: Chris Mcowen Cc: [email protected] Subject: Re: [R-sig-Geo] spatially clustered factors? On Mon, 1 Jul 2013, Chris Mcowen wrote: > Dear list, first let me apologise, i am an ecologist and this is my > first foray into spatial statistics. > > > > I have, for a number of regions, the factor that best explains > variation in the yield (fisheries catch) obtained within that region, > the factor has 4 levels - ChlA, SST, Effort or none. See joincount.test for single comparisons, or joincount.multi for multiple comparisons by join "colours" in spdep. You'll also need neighbour lists, explained in: vignette("nb") in the most recent version of that package. Hope this helps, Roger > > > > What i am essentially wanting to know is, is there a spatial pattern > to the data? (clumped, over-dispersed or random) > > > > For example if region 1 is classed as Effort, is it more or less > likely that the adjoining region (region 2) will be of the same > factor, or does it makes no difference. > > > > I have seen lots of packages that allow this to be done for numerical > data but have not found one for factors. > > > > Please see below for an example of the data. Where latitude is the > centroid of the region and factor is the source of variation. > > > > clusters <- structure(list(Latitude = c(4.8261, 26.127123, 3.409063, > -31.964573, 11.524328, 10.857926, 30.95066, 6.322733, 40.963009, > -4.370738, 53.77057, -46.270909, 51.431808, 50.091992, -12.606217, > 16.26404, -27.513126, -40.976427, -40.491914, -35.169487, -16.739053, > -22.651113, 30.445027, -27.701939, -17.154608, -10.147356, -29.117245, > 57.472215, 45.538569, 65.31731, 75.308501, 54.063299, 45.194528, > 41.079154, -35.169487, 51.431808, 24.647845, 68.201714, 41.262656, > 24.976371, 33.251908, 16.347456, 30.95066, -1.408364, 37.054319, > 23.843305, 57.400753, 8.712258), Factor = structure(c(1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 4L, 4L, 4L, > 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L), .Label = c("ChlA", "Effort", > "SST", "Unidentified"), class = "factor")), .Names = c("Latitude", > > "Factor"), class = "data.frame", row.names = c(NA, -48L)) > > > > > > Thanks, > > > > Chris > > > > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-Geo mailing list > [email protected] > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > -- Roger Bivand Department of Economics, NHH Norwegian School of Economics, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: [email protected] _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
