Dear list members, We have a bivariate point pattern (two tree species) in a linear transect and would like to obtain a null model equivalent to the one provided by rshift in 2D to test the independence of both populations (in spatstat)
We are using spatstat, but this option does not seem available at the moment, or we can't find it (the option available tests the complete spatial randomness of one population (p) once the other population is fixed (s) but does not keep the pattern of the second population (p) unchanged- which is a problem because both populations are clustered in our case) An example of our code follows: T1 is a point pattern on a linear transect as follows: > T1 Point pattern on linear network 232 points Multitype, with possible types: p, s Linear network with 2 vertices and 1 line Enclosing window: rectangle = [-1, 101] x [-1, 1] units We used multiple pair correlation functions (linearpfccross) We computed an envelope to test the hypothesis of complete spatial randomness and independance: T1.env = envelope.lpp ( T1, fun = linearpcfcross , nsim = 30 , i = "s", j = "p") If anybody has experienced a similar problem or has some hints on how to proceed we would be very grateful Thanks in advance cheers, Ignacio? [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo