A SPATIAL SCAN STATISTIC FOR STOCHASTIC SCAN PARTITIONS

This article develops a spatial scan statistic for homogeneity analysi s of point processes that utilizes stochastic scan partitions. The der ivation of the sampling distribution for the statistic yields an exact test. This test has the potential for improved power over conventiona l alternatives when the point process is embedded in an underlying con tinuous random field and is recommended in situations for which the lo cation of subregions of nonhomogeneity in the point process correspond to regions in the underlying field that can be segmented as distinct from their surroundings. The application to the detection of clustered microcalcifications in digital mammography is investigated as a motiv ating example.