ISM Research Memorandum
No.
1104
Title:
On parameter estimation based on the contact distance for certain superposed Neyman-Scott cluster fields
Author(s):
TANAKA, Ushio (The Institute of Statistical Mathematics)
Key words:
superposed Neyman-Scott cluster field; contact distance; nearest neighbor distance function; J-function; NND intensity analysis; unimodality; parameter estimation
Abstract:
We consider parameter estimation of the superposed Neyman-Scott cluster field.
This is typical of cluster point pattern model.
We show that parameters of this model whose J-functions satisfy certain
condition can be determined completely via an isotropic and non-homogeneous
Poisson maximum likelihood analysis based on contact distance,
which is defined as the shortest distance from the given location to the
nearest point. The J-function is known as a useful tool assigning an index
to spatial point pattern interaction. A sufficient condition for our method
to hold is that the maximum log-likelihood function is unimodal.
For such a cluster field, the proposed estimation procedure also
enables us to generalize the number of the superposition.