A neighbor is “somebody” who is:
See Anselin & Rey (2014) for an in-detail discussion and more types of W.
Sharing boundaries to any extent
Weight is (inversely) proportional to distance between observations
Weights are assigned based on discretionary rules loosely related to geography
No neighbors receive zero weight: wij = 0
Neighbors, it depends, wij can be:
One wij = 1 → Binary
Some proportion (0 < wij < 1, continuous) which can be a function of:
Should be based on and reflect the underlying channels of interaction for the question at hand.
In some applications (e.g. spatial autocorrelation) it is common to standardize W
The most widely used standardization is row-based: divide every element by the sum of the row:
where wi· is the sum of a row.
A course on Geographic Data Science by Dani Arribas-Bel is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.