i) Point or georeferenced data, where each point in space has a unique spatial identifier (e.g. longitude and latitude coordinates) and where the vector of observations is random and varies continuously over a fixed space. This is often referred to as geostatistical data. We thus have a continuous fixed space where the location of each data point is random. ii) Point pattern data, similar to georeferenced data but where the space is also random. Such datasets are, for example, used to count events and their clustering. iii) Areal (or lattice) data, where the space (of a regular or irregular shape) is fixed but partitioned into a finite number of areal units with well-defined boundaries, for example census (or other administrative) tracts.