<Dd> z a = ∑ p l a p F p + ε a (\ displaystyle \ mathbf (z) _ (a) = \ sum _ (p) \ ell _ (ap) \ mathbf (F) _ (p) + (\ boldsymbol (\ varepsilon)) _ (a)) </Dd> <P> and the independence of the factors and the errors: F p ⋅ ε a = 0 (\ displaystyle \ mathbf (F) _ (p) \ cdot (\ boldsymbol (\ varepsilon)) _ (a) = 0). In the above example, the hyperplane is just a 2 - dimensional plane defined by the two factor vectors . The projection of the data vectors onto the hyperplane is given by </P> <Dl> <Dd> z ^ a = ∑ p l a p F p (\ displaystyle (\ hat (\ mathbf (z))) _ (a) = \ sum _ (p) \ ell _ (ap) \ mathbf (F) _ (p)) </Dd> </Dl> <Dd> z ^ a = ∑ p l a p F p (\ displaystyle (\ hat (\ mathbf (z))) _ (a) = \ sum _ (p) \ ell _ (ap) \ mathbf (F) _ (p)) </Dd>

Who used factor analysis technique for classification of personality