[R-sig-Geo] circular window for spatial statistics (spatstat package)

[Michael Friendly]

Hi list,

A biology student I'm trying to help has done a study planting 20 seeds 
in circular pots under varying conditions and wants to analyze the 
degree of clustering
(and other measures) in the seeds that germinate (0-20) in relation to
the factors that differentiate pots (treatment, type of seed, ...)

The data structure is something like a data frame for all the 
germinating seeds, recording (X,Y) location and maybe some other
measure like size after xx days:

PotID Treatment SeedType  X    Y  size

Assume that the (X,Y) locations are referred to a circle of fixed radius, R.
I'm not very familiar with analysis of spatial point processes, but it 
seems that the spatstat package could handle this.  (Is there something
better?)  I've read the documentation, but can't find an example of how 
to specify a circular window for the ppp object that would contain the
data and the window.

thanks,
-Michael

-- 
Michael Friendly     Email: friendly AT yorku DOT ca
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
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