I have data for participants from 12 different countries. As this number is too small for TYPE=COMPLEX or TYPE=TWOLEVEL analyses, I have been trying to account for the clustering using dummy variables.
ANALYSIS: TYPE = GENERAL; MODEL: y ON x1 x2 x3 x1byx2 x1byx3 x2byx3 d1-d11;
However, when I add the 11 dummy variables to my model, as above, I get the following warnings/errors:
WARNING: THE SAMPLE COVARIANCE OF THE INDEPENDENT VARIABLES IS SINGULAR. PROBLEM INVOLVING VARIABLE D11.
THE MODEL ESTIMATION TERMINATED NORMALLY
THE STANDARD ERRORS OF THE MODEL PARAMETER ESTIMATES COULD NOT BE COMPUTED. THE MODEL MAY NOT BE IDENTIFIED. CHECK YOUR MODEL. PROBLEM INVOLVING THE FOLLOWING PARAMETER: Parameter 18, Y ON D11