This function pools together individuals with the same encounter capture-recapture history along specified directions given by columns.
group_data_gen(X, effX, s)
matrix with grouped capture-recapture histories and counts in the last column
matrix of capture-recapture histories
vector with numbers of individuals with that particular capture-recapture history
scalar or vector of columns along which the grouping should be done
Olivier Gimenez <olivier.gimenez@cefe.cnrs.fr>, Roger Pradel, Rémi Choquet