# The FACTOR Procedure

### Time Requirements

The time required to compute…

is roughly proportional to

an overall factor analysis

the correlation matrix

PRIORS=SMC or ASMC

PRIORS=MAX

eigenvalues

final eigenvectors

generalized Crawford-Ferguson

family of rotations,

PROMAX, or HK

ROTATE=PROCRUSTES

Each iteration in the PRINIT or ALPHA method requires computation of eigenvalues and f eigenvectors.

Each iteration in the ML or ULS method requires computation of eigenvalues and eigenvectors.

The amount of time that PROC FACTOR takes is roughly proportional to the cube of the number of variables. Factoring 100 variables, therefore, takes about 1000 times as long as factoring 10 variables. Iterative methods (PRINIT, ALPHA, ULS, ML) can also take 100 times as long as noniterative methods (PRINCIPAL, IMAGE, HARRIS).