Austin Hughes' data: a point pattern of displaced amacrine cells in the retina of a rabbit. A marked point pattern.

`data(amacrine)`

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` |

See `ppp.object`

for details of the format.

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).

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.