All analyses were run using Mx (Neale et al., 2003). Model selection was determined by the −2 log-likelihood difference method. For each parameter dropped, the −2 log-likelihood of that model was compared to the −2 log-likelihood of the saturated model. If the submodel’s −2 log-likelihood differed significantly according to a 1 degree of freedom chi-square test (p < 0.05) from the saturated model, the model fit was judged to be significantly worse and the parameter should be retained in the model.
