* An example with SPSS.
* from DeCarlo, L. T. (1998). Signal detection theory and
  generalized linear models. Psychological Methods, 3, 186-205.
set width=80 length=none.
title "Example 2a from Macmillan & Creelman, 1991, p.31".
* Note - responses are coded yes=1 and no=0.
data list list /hypno signal yes count *.
begin data
0 0 0 69
0 0 1 31
0 1 0 31
0 1 1 69
1 0 0 41
1 0 1 59
1 1 0 11
1 1 1 89
end data.
compute sighypno=signal*hypno.
weight by count.
logistic regression yes with hypno signal sighypno
  /criteria lcon(0).
* Next is the restricted model without the interaction term.
* The -2 log L can be used to test for constant dj.
logistic regression yes with hypno signal
  /criteria lcon(0).