Analysing spatial point patterns in R - CSIRO

22 Introduction to spatstat
X
> X
Simply typing the name of the dataset gives you some basic information:
planar point pattern: 71 points
window: rectangle = [0, 96] x [0, 100] units (one unit = 0.1 metres)
Let’s study the intensity (density of points) in this point pattern. For a few basic summary
statistics, type
> summary(X)
Planar point pattern: 71 points
Average intensity 0.0074 points per square unit (one unit = 0.1 metres)
Window: rectangle = [0, 96]x[0, 100]units
Window area = 9600 square units
Unit of length: 0.1 metres
The coordinates are expressed in decimetres (0.1 metre), so the average intensity is 0.0074
trees per square decimetre or 0.74 trees per square metre.
To get an impression of local spatial variations in intensity, we can plot a kernel estimate of
intensity:
> plot(density(X, 10))
density(X, 10)
0.002 0.004 0.006 0.008 0.01 0.012 0.014
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