A complete revision to the theory, practice and applications of factor analysis in chemistry--a mathematical technique for studying matrices of data. Methods of factor analysis that are quicker, more cost effective and easier as a result of new computer applications are included. Topics added include A and R model analysis, singular value decomposition, NIPALS decomposition and iterative key set factor analysis. New methods for rank determination, statistical methods for target testing, errors in factor loadings and weighted factor analysis are also treated in this edition. Special methods of factor analysis such as classical factor analysis, common factors, communality, partial least squares, and modeling and self modeling methods of evolutionary factor analysis are also included.