ABSTRACT
The methods presented in previous chapters were primarily concerned with examining item-to-item correlations or correlations among multi-item or single-item domains. Items in multi-item scales in the previous chapter are often based upon and con„rmed by factor analysis. Afactor is alatent variable, that is, an unobserved or hidden variable; the term factor may be de„ned and interchanged with the terms domain, construct, or concept. A latent variable is ahypothetical construct that is not directly observed, but whose existence is inferred from the way that it in¦uences the observed or manifest variables. Examples of a latent variable include depression and anxiety.
