The longleaf data as used in Rathburn and Cressie (1994) is now also part of the "spatstat" package in R. The description below is taken from the package.
The data record the locations and diameters of 584 Longleaf pine (Pinus palustris) trees in a 200 x 200 metre region in southern Georgia (USA). They were collected and analysed by Platt, Evans and Rathbun (1988). This is a marked point pattern; the mark associated with a tree is its diameter at breast height (dbh), a convenient measure of its size. Several analyses have considered only the “adult” trees which are conventionally defined as those trees with dbh greater than or equal to 30 cm. The pattern is regarded as spatially inhomogeneous.
The csv file contains three columns:
- x: x-coordinate in metres
- y: y-coordinate in metres
- marks: tree diameter at breast height
Rathbun, Stephen L., and Noel Cressie. "A space-time survival point process for a longleaf pine forest in southern Georgia." Journal of the American Statistical Association 89.428 (1994): 1164-1174.