spgwr (version 0.6-36)

gwr.tricube: GWR tricube weights function

Description

The function returns a vector of weights using the tricube scheme:

$$w_{ij}(g) = (1 - (d_{ij}/d)^3)^3 $$ if \(d_{ij} <= d\) else \(w_{ij}(g) = 0\), where \(d_{ij}\) are the distances between the observations and \(d\) is the distance at which weights are set to zero.

Usage

gwr.tricube(dist2, d)

Value

matrix of weights.

Arguments

dist2

vector of squared distances between observations

d

distance at which weights are set to zero

Author

Roger Bivand

References

Fotheringham, A.S., Brunsdon, C., and Charlton, M.E., 2000, Quantitative Geography, London: Sage; C. Brunsdon, A.Stewart Fotheringham and M.E. Charlton, 1996, "Geographically Weighted Regression: A Method for Exploring Spatial Nonstationarity", Geographical Analysis, 28(4), 281-298; http://gwr.nuim.ie/

See Also

gwr.sel, gwr

Examples

plot(seq(-10,10,0.1), gwr.tricube(seq(-10,10,0.1)^2, 6.0), type="l")