Methods of varimax rotation in factor analysis with applications in clinical and food chemistry

Orthogonal rotations, e.g. the varimax rotation, are common practice in factor anlaysis. However, the term varimax rotation does not refer to a unique procedure, since several different types of rotation are possible. In this paper six different types of rotation are examined (raw varimax of loadings, normal varimax of loadings, raw and normal varimax of scores, eigenvalue-weighted varimax of loadings and Arthur varimax) from both a theoretical and practical point of view. It can be concluded that an adequate application of these methods can often simplify the interpretation of the calculated factors.