
192 Spatial Point Patterns: Methodology and Applications with R
maximum likelihood estimator is the Allard-Fraley [11] cluster set. The Dirichlet tessellation in-
duced by the point pattern is computed; the k sm allest tiles (ranked by tile area) are identified, where
k is determined b y maximising a likelihood criterion analogou s to the likelihood ratio test statistic
described a bove; the union of th ese k smallest tiles is the cluster set.
Figure 6.3 0. Artificial example o f high-intensity region . Left: simulated data from Poisson process
with intensity 100 inside the letter R, and intensity 20 outside. Right: Nonparametric (Allard-Fraley)
estimate ...