

members(multiv)                              R Documentation

_C_l_u_s_t_e_r _M_e_m_b_e_r_s_h_i_p_s

_D_e_s_c_r_i_p_t_i_o_n_:

     From a succession of agglomerations produced by a hier-
     archical routine in function `hierclust' or `hclust',
     determine cluster assignments of all objects, at all
     levels of the hierarchy.

_U_s_a_g_e_:

     members(a)

_A_r_g_u_m_e_n_t_s_:

       a: output produced by functions `hierclust' (or
          'hclust' or `mclust').

_V_a_l_u_e_:

     matrix of dimensions `n' by `n-2' giving cluster
     assignments to the 2, 3, ...{} n-1 cluster partitions
     of the hierarchy.  This corresponds to levels `n-2' to
     2.  The observations correspond to the rows, and are in
     sequence, `1, 2, ...{}'.  Column `j' specifies which of
     the `2, 3, ...{} j-1' clusters each observation is
     associated with at the level `j-1' of the agglomerative
     process.  The two clusters which merge in going from
     level `j-1' to `j-2' are replaced in the `j-2'nd column
     with the lower of the two cluster sequence numbers.

_N_O_T_E_:

     The time requirement of 'members' is `O(n^3)'.  Sample
     time for Sun SPARCstation 1, with 600 observations: 303
     secs.

_S_e_e _A_l_s_o_:

     Functions `hierclust', `hclust', or `mclust' produce
     the array containing the sequence of agglomerations
     which can be used as input for `members'.

_E_x_a_m_p_l_e_s_:

     h <- hierclust(a, method=2)
     k <- members(h)

