wardinit {ClustGeo}

Ward aggregation measures between singletons

Description

This function calculates the Ward aggregation measures between pairs of singletons.

Usage

wardinit(D, wt = NULL)

Arguments

D

a object of class "dist" with the dissimilarities between the n obsevations. The function as.dist can be used to transform an object of class matrix to object of class "dist".

wt

vector with the weights of the observations. By default, wt=NULL corresponds to the case where all observations are weighted by 1/n.

Details

The Ward agreggation measure between to singletons i and j weighted by wi and wj is : (wiwj)/(wi+wj)dij^2 where dij is the dissimilarity between i and j.

Value

Returns an object of class dist with the Ward aggregation measures between the n singletons.

References

M. Chavent, V. Kuentz-Simonet, A. Labenne, J. Saracco. ClustGeo: an R package for hierarchical clustering with spatial constraints. Comput Stat (2018) 33: 1799-1822.