[R] code for automating the sem package

Greetings, I am wondering if anyone has written programs to automate model fitting with the sem package, where one could specify a 'saturated' model and sequentially fit models with different combinations of parameters removed, while outputting fit data/parameters involved for each model. Than

[R] Summarizing dummy coefficients in sem package

Greetings, I am working in the sem package on a model with 3 exogenous variables (2 are nominal-categorical), and 4 endogenous, continuous variables. To use sem with the nominal variables, I created dummy variables. Now, in my sem output I have estimates for path coefficients for the relatio

[R] appropriate covariance matrix for multiple nominal exogenous and multiple continuous endogenous variables in SEM

Hi, I would like to use the sem package to perform a path analysis (no latent variables) with a mixture of 2 nominal exogenous, 1 continuous exogenous, and 4 continuous endogenous variables. I seek advice as to how to calculate the appropriate covariance matrix for use with the sem package.