Multitype Markov point processes: some approximations

Approximations are derived for some simple properties of a Strauss-type spatial point process with two types of point, on the assumption that the interactions between points are fairly weak and that boundary effects are negligible. In particular, expansions are obtained of the reduced second moment measure Kij used in the statistical analysis of spatial point patterns. It is found that these expansions may be useful in the estimation of the inter-point interactions and their ranges.