MEdims                 package:nlme                 R Documentation

_C_a_l_c_u_l_a_t_e _d_i_m_e_n_s_i_o_n_s _i_n _m_i_x_e_d-_e_f_f_e_c_t_s

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

     Calculate the dimensions of various arrays used to represent a
     mixed-effects model.

_U_s_a_g_e:

     MEdims(groups, ncols)

_V_a_l_u_e:

     a list of dimensions 

       N: total number of observations in the original data.

  ZXrows: number of rows in the `ZXy' array.  This can be different
          from `N' if the condensed linear model has been decomposed by
          `MEdecomp'.

  ZXcols: number of columns in the `ZXy' array.

       Q: number of levels of random effects.

 StrRows: total number of rows in the arrays to be stored if
          conditional estimates of random effects and fixed effects are
          to be calculated.

    qvec: a vector of length `Q+2' giving the number of columns in the
          model matrices for each level of random effects, the fixed
          effects and the response.

   ngrps: a vector of length `Q' giving the number of groups at each
          level of the random effects.

   DmOff: a vector of length `Q' giving the offsets into the
          concatenated relative precision factor arrays.

   ncols: a vector of length `Q' giving the number of columns in the
          model matrices at each level of random effects.

    nrot: a vector of length `Q+2' giving the number of columns to the
          right of the current level in the `ZXy' array that must be
          rotated in the decomposition.

   ZXoff: a list of vectors of length `Q+2' giving the offsets into the
          `ZXy' array for the beginning of the model matrix in each
          group at each level.

   ZXlen: a list of vectors of length `Q+2' giving the lengths (number
          of rows) of the model matrix in each group at each level.

   SToff: a list of vectors of length `Q+2' giving the offsets into the
          stored data array for the beginning of the model matrix in
          each group at each level.

  DecOff: a list of vectors of length `Q+2' giving the offsets into the
          decomposed data array for the beginning of the model matrix
          in each group at each level.  These offsets differ from
          `SToff' when there are nested random effects.  The `DecOff'
          entry for an outer grouping factor points to the beginning of
          the block and the `SToff' entry points to the beginning of
          the last section of the block.

  DecLen: a list of vectors of length `Q+2' giving the lengths (number
          of rows) in the block to be decomposed for each group at each
          level.

_A_u_t_h_o_r(_s):

     Douglas Bates bates@stat.wisc.edu

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

     `MEestimate'

