# [R] help on spatial data

Ronaldo Reis Jr. chrysopa at insecta.ufv.br
Wed May 21 18:41:26 CEST 2003

```Hi,

I have a dataset with x and y coordinates and in each point I have an
identity of point, in some cases I can have more then one identity by point.

My dataset is something like this:

> x <- rep(c(1:4),4)
> y <- rep(c(1:4),c(4,4,4,4))
> area1 <- sample(factor(rep(c("a","b","c","d"),4)))
> area2 <-
as.factor(c(rep(c("a","b"),c(2,2)),rep(c("a","b"),c(2,2)),rep(c("c","d"),c(2,2)),rep(c("c","d"),c(2,2))))

to view the spatial grid:

> plot(y~x,pch=levels(area1)[codes(area1)])
> plot(y~x,pch=levels(area2)[codes(area2)])

I have several areas with different distribution.

I need to compute the distance and the diference between points.

My hypothesis is that the diference between two points increase with the
distance between these points.

In this example, the fisrt area (area1) have a random distribution, and my
hypothesis is false, in second area (area2) I have an aggregated distribution
and my hypothesis is true.

I real data I can have several levels of aggregation, I need testing these
difference of aggregations.

I try to use the Kfn from spatial package, but I dont succeed.

R have any package to make this analyse?

What I need to read for this?

Thanks for all

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