  The calculation of common factor means in structured means analysis (SMM) is
considered. The SMM equations imply that the unique factors are defined as
having zero means. It was shown within the one factor solution that this
definition implies larger absolute common factor loadings to co-occur with
larger absolute expectations of the observed variables in the single group
case. This result was illustrated by means of a small simulation study. It is
argued that the proportionality of factor loadings and observed means should be
critically examined in the context of SMM. It is recommended that researchers
should freely estimate the observed expectations, whenever, the proportionality
of loadings and observed means does not make sense. It was also shown that for
a given size of observed expectations, smaller common factor loadings result in
larger common factor mean estimates. It should therefore be checked whether
variables with very small factor loadings occur when SMM results in very large
absolute common factor means.
