Example (CSLOGISTIC command)

Suppose that dependent variable Z has three categories, and factors A and B each have three levels.

CSLOGISTIC z BY a b
  /PLAN FILE='/survey/myfile.csplan'
  /CUSTOM LABEL = ‘Effect A for All Logits’
     LMATRIX = a 1 0 -1; a 0 1 –1
  /CUSTOM LABEL = ‘Effect A for 1st Logit, Effect B for 2nd Logit’
     LMATRIX = ALL 0 1 0 –1 0 0 0 0 0 0 0 1 0 –1;
       ALL 0 0 1 –1 0 0 0 0 0 0 0 0 1 –1
     KMATRIX = 0; 0.
  • The dependent variable Z has three categories, so there will be two logits.
  • The MODEL subcommand is not specified; thus the default model—which includes the intercept and main effects for A and B—is used.
  • The first CUSTOM subcommand tests whether the effect of factor A is 0 across both logits.
  • The second CUSTOM subcommand specifies different contrast coefficients for each logit. In particular, the L matrix tests the effect of factor A for the first logit and factor B for the second logit. The KMATRIX keyword explicitly states that each linear combination that is formed from the contrast coefficients and the parameter estimates is tested against the value 0.