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 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).