Ncontributors with holding-indicatorThe aggregates (columns of x) are grouped by a holding indicator.
Within each holding group, the number of unique groups (output) is set to be equal.
NcontributorsHolding(x, groups, holdingInd = NULL)Vector of numbers of unique groups
A (sparse) dummy matrix
Vector of group categories
Vector of holding group categories
Øyvind Langsrud
A representative within the holding group is used to calculate output by Ncontributors.
The one with maximal column sum of x is chosen as the representative.
Normally this will be an aggregate representing the holding group total.
When holdingInd is NULL (default), the function is equivalent to Ncontributors.