[R] SpatStat Kest - Error Message help

[Rolf Turner]

(1) Questions about contributed packages (such as spatstat) should in the
first instance be directed to the authors/maintainers of the package (in
this case Adrian Baddeley and myself) rather than to the list.

(2) It's very hard to say what's causing your problem without digging into
the specifics.  If you could email the problematic data set (it's only 17
points, after all!) to me and/or Adrian, we could probably figure out
what's causing the hiccup.

(3) It sound's like you are using roll-your-own code to create
(effectively) a critical envelope for your estimated K function. Why
aren't you using the built-in function envelope()?

(4) I believe that 999 replicates is usually overkill for Monte Carlo
inference; 99 reps is probably adequate.  Other uncertainties that are
always present in any real data set dwarf the lack of precision resulting
from using ``only'' 99 reps.  (Ninety-nine reps is the default in
envelope(); but you can set the number of reps to anything you want,
including 999 if you insist.)

(5) What does ``statistical significance of a point pattern'' mean?

			cheers,

				Rolf Turner
				rolf at math.unb.ca

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On Thu, 1 Sep 2005, DrakeGis wrote:

> Hi I'm working with the function Kest in the package SpatStat (under LINUX
> with R 2.1.0). In order to evaluate the statistical significance of my
> point pattern I'm doing 999 Montecarlo replications. The script that use
> the Kest function runs OK for most of the different point patterns that I
> have but for a particular point pattern, which have only 17 points, it
> runs until the 34th iteration and then I receive this message:
>
> Error in "[<-"(`*tmp*`, index, value = NULL) :
> 	incompatible types (1000) in subassignment type fix
> Execution halted
>
> Do you have any idea about what could be the cause of this ? Thanks in
> advance.