Hi Jesús. I think of this as something of an open research problem, so I'm curious to hear what others have to say. I looked at the reference you sent (which is new to me, looks interesting!)
Is your original data a spatial point pattern which you've smoothed into a map (as in spatial point processes)? Or do you have variables observed for spatial regions (as in geostatistics)? Seth On Thu, Feb 20, 2014 at 1:51 PM, Jesús Muñoz <[email protected]> wrote: > Dear colleagues, > > I needed to measure the association degree (and ideally its p-value) between > two maps, one representing richness of European bryophytes and the other > vascular plant richeness. From the maps it is clear the two patterns are > reversed: bryophytes 'rule' in the north, and vascular plant richness is > higher in southern Europe. > > I have used isodata algorithm followed by a Maximum-likelihood > classification to generate a map showing four different areas in Europe > (lowbryo-lowvasc, lowbryo-highvasc, highbryo-lowvasc, and > highbryo-highvasc). Additionally, I would like to run a correlation analysis > but corrected for the univariate spatial correlation of each variable > (bryophytes and vascular plant richness); a global correlation map-to-map is > meaningless here. > > I found a statistic that would suit my needs (Lee, S.-I. 2001. Developing a > bivariate spatial association measure: An integration of Pearson's r and > Moran's I. Journal of Geographical Systems 3(4): 369-385). It is implemented > in 'The Map Comparison Kit' (http://www.riks.nl/mck/), but it return values > outside the -1 to 1 values, which makes me think there is something wrong in > the code or the statistic. > > Can somebody guide me to a R package allowing me to measure the association > between these two grids? > > thanks in advance, > > Jesús > > > > > > ************************************************************************* > > Jesús Muñoz PhD e-mail: [email protected] > > Real Jardín Botánico (CSIC) > > C/ Claudio Moyano 1 tlf. +34 91 420 3017 > > E-28014 Madrid fax. +34 91 420 0157 > > ESPAÑA (Spain) > > > > http://www.masterenbiodiversidad.org > > > > http://www.rjb.csic.es/jardinbotanico/jardin/contenido.php?Pag=413&tipo=cien > tifico&cod=66 > > > > KRAKEN research group (environmental modelling, data processing & analysis): > > http://www.unex.es/investigacion/grupos/kraken > > > > SYNTHESYS: EU funds short visits to our institution: > > http://www.synthesys.info/index.htm > > ************************************************************************* > > > > > > __________ Información de ESET Endpoint Security, versión de la base de > firmas de virus 9449 (20140220) __________ > > ESET Endpoint Security ha comprobado este mensaje. > > http://www.eset.com > > > [[alternative HTML version deleted]] > > > _______________________________________________ > R-sig-Geo mailing list > [email protected] > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
