Suppose I have two sets of (x,y) points like this: x1<-runif(n=10) y1<-runif(n=10) A<-cbind(x1,y1)
x2<-runif(n=10) y2<-runif(n=10) B<-cbind(x2,y2) I would like to measure how similar the two sets of points are. Something like a correlation coefficient, where 0 means the two patterns are unrelated, and 1 means they are identical. And in addition I'd like to be able to assign a p-value to the calculated statistic. cor(x1,x2) cor(y1,y2) gives two numbers instead of one. cor(A,B) gives a correlation matrix I have looked a little at spatial statistics. I have seen methods that, for each point, search in some neighbourhood around it and then compute the correlation as a function of search radius. That is not what I am looking for. I would like a single number that summarises the strength of the relationship between the two patterns. I will do procrustes on the two point sets first, so that if A is just a rotated, translated, scaled, reflected version of B the two patterns will superimpose and the statistic I'm looking for will say there is perfect correspondence. Thanks very much for any help in finding such a statistic and calculating it using R. Bill ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
