amacrine
Hughes' Amacrine Cell Data
Austin Hughes' data: a point pattern of displaced amacrine cells in the retina of a rabbit. A marked point pattern.
Usage
data(amacrine)format
An object of class "ppp"
representing the point pattern of cell locations.
Entries include
x Cartesian $x$-coordinate of cell
y Cartesian $y$-coordinate of cell
marks factor with levels off and on
indicating ``off'' and ``on'' cells
}
See ppp.object for details of the format.
source
Peter Diggle, personal communication
Notes
Austin Hughes' data: a point pattern of displaced amacrine cells in the retina of a rabbit. 152 ``on'' cells and 142 ``off'' cells in a rectangular sampling frame.
The true dimensions of the rectangle are 1060 by 662 microns. The coordinates here are scaled to a rectangle of height 1 and width $1060/662 = 1.601$ so the unit of measurement is approximately 662 microns.
The data were analysed by Diggle (1986).
References
Diggle, P. J. (1986). Displaced amacrine cells in the retina of a rabbit: analysis of a bivariate spatial point pattern. J. Neurosci. Meth. 18, 115--125.