MARG Call

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MARG Call

evaluates marginal totals in a multiway contingency table

CALL MARG( locmar, marginal, dim, table, config);

The inputs to the MARG subroutine are as follows:

dim: specifies a vector containing the number of variables and the number of their possible levels in a contingency table. If dim is 1 ×v, then there are v variables, and the value of the ith element is the number of levels of the ith variable.
table: specifies an array containing the number of observations at each level of each variable. Variables are nested across columns and then across rows.
config: specifies an array containing the marginal totals to be evaluated. Each column specifies a distinct marginal.
locmar: returns a vector of indices to each new set of marginal totals specified by config. A marginal total is exhibited for each level of the specified marginal. These indices help locate particular totals.
marginal: returns a vector of marginal totals.

The matrix table must conform in size to the contingency table specified in dim. In particular, if table is n ×m, the product of the entries in the dim vector must equal nm. In addition, there must be some integer k such that the product of the first k entries in dim equals m. See the description of the IPF function for more information on specifying table.

For example, consider the no-three-factor-effect model for Bartlett's data as described in Bishop, Fienberg, and Holland (1975):

   dim={2 2 2};
   table={156   84   84  156,
          107  133   31  209};
   config={1 1 2,
           2 3 3};
   call marg(locmar,marginal,dim,table,config);

These statements return

        LOCMAR      1 row     3 cols  (numeric)

                      1       5       9

      MARGINAL    1 row    12 cols  (numeric)

   263     217     115     365     240     240     138
  :342     240     240     240     240

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