Hitherto latent variable modelling has hovered on the fringes of the statistical
mainstream but if the purpose of statistics is to deal with real problems, there
is every reason for it to move closer to centre stage. In the social sciences
especially, latent variables are common and if they are to be handled in a truly
scientific manner, statistical theory must be developed to include them. This
book aims to show how that should be done.This second edition is a complete
re-working of the book of the same name which appeared in the Griffin's
Statistical Monographs in 1987. Since then there has been a surge of