The lavaan model syntax describes a latent variable model. Often, the user wants to see the covariance matrix generated by their model for diagnostic purposes. However, their data may have far more columns of information than what is contained in their model.
inspectSampleCov(model, data, ...)The model that will be fit by lavaan.
The data frame being used to fit the model.
Other arguments to sem for how to deal with
multiple groups, missing values, etc.
One must supply both a model, coded with proper model.syntax and
a data frame from which a covariance matrix will be calculated. This function
essentially calls sem, but doesn't fit the model, then uses
lavInspect to get the sample covariance matrix and meanstructure.