Independent pathway model, which allows the covariance structure to differ among the 4 sectors; specifically, this model allows the 4 sector variables to load independently onto the latent genetic and environmental factors. ECindicates latent unique environmental factor common to all sectors; ES, unique environmental factor specific for a given sector; FC, familial factor common to all sectors; FS, familial factor specific for a given sector. Observed variables are in rectangles and latent variables are in circles.