Ripley's K function
Encyclopedia of environmetrics, (2002)Abstract
Ripley’s Kt function is a tool for analyzing com-
pletely mapped spatial point process data (see Point
processes, spatial), i.e. data on the locations of
events. These are usually recorded in two dimensions,
but they may be locations along a line or in space.
Here I will only describe Kt for two-dimensional
spatial data. Completely mapped data include the
locations of all events in a predefined study area.
Ripley’s Kt function can be used to summarize
a point pattern, test hypotheses about the pattern,
estimate parameters and fit models. Bivariate or
multivariate generalizations can be used to describe
relationships between two or more point patterns.
Applications include spatial patterns of trees 10, 20,
29, herbaceous plants 28, bird nests 11 and dis-
ease cases 7. Details of various theoretical aspects
of Kt are in books by Ripley 26, Diggle 6,
Cressie 4, Stoyan and Stoyan 30. Examples of
computation and interpretation can be found in those
books and also in Upton and Fingleton 32.