Latent Variable Modelling: Old and New Approaches

To find he precursor of contemporary latent variable modelling one must go back to the beginning of the 20th century and Charles Spearman’s invention of factor analysis. This was followed, half a century later, by latent class and latent trait analysis and, from the 1960’s onwards, by covariance structure analysis. The most recent additions to the family have been in the area of time series. We shall briefly review each of these fields in turn as a foundation for the evaluations and comparisons which we shall need to make later.