Maximum Likelihood Factor Analysis Example -- Harman -- pg 


Variables:
y1 total population
y2 median school years
y3 total employment
y4 misc. profess services
y5 median value house


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data socfac (type=corr);
  _type_='corr';
input _name_ $ y1 y2 y3 y4 y5;
cards;
y1 1.00000 0.00975 0.97245 0.43887 0.02241
y2 0.00975 1.00000 0.15428 0.69141 0.86307
y3 0.97245 0.15428 1.00000 0.51472 0.12193
y4 0.43887 0.69141 0.51472 1.00000 0.77765
y5 0.02241 0.86307 0.12193 0.77765 1.00000
;
proc factor method=ml priors=smc heywood rotate=varimax rotate=promax;
  title 'ML Factor Analysis Example';
run;

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                        ML Factor Analysis Example                      

Initial Factor Method: Maximum Likelihood

                   Prior Communality Estimates: SMC

                    Y1        Y2        Y3        Y4        Y5
              0.968593  0.822273  0.969182  0.785718  0.847008

    Preliminary Eigenvalues:  Total = 76.1173815  Average = 15.2234763

                        1           2           3           4           5
 Eigenvalue       63.7028     13.0539      0.3275     -0.3473     -0.6195
 Difference       50.6489     12.7263      0.6748      0.2722
 Proportion        0.8369      0.1715      0.0043     -0.0046     -0.0081
 Cumulative        0.8369      1.0084      1.0127      1.0081      1.0000

          2 factors will be retained by the PROPORTION criterion.

Iter Criterion    Ridge   Change   Communalities
  1    0.34305    0.000  0.04710   1.00000 0.80672 0.95058 0.79348 0.89411
  2    0.30713    0.000  0.03069   1.00000 0.80821 0.96024 0.81047 0.92480
  3    0.30670    0.000  0.00629   1.00000 0.81149 0.95949 0.81676 0.92023
  4    0.30665    0.000  0.00218   1.00000 0.80985 0.95963 0.81498 0.92241
  5    0.30665    0.000  0.00071   1.00000 0.81019 0.95956 0.81569 0.92187


                     Convergence criterion satisfied.


Initial Factor Method: Maximum Likelihood

     Significance tests based on 10000 observations:

        Test of H0: No common factors.
             vs HA: At least one common factor.

        Chi-square = 63803.130   df = 10   Prob>chi**2 = 0.0001

        Test of H0: 2 Factors are sufficient.
             vs HA: More factors are needed.

        Chi-square = 3065.006   df = 1   Prob>chi**2 = 0.0001

     Chi-square without Bartlett's correction = 3066.1812237
     Akaike's Information Criterion = 3064.1812237
     Schwarz's Bayesian Criterion = 3056.9708833
     Tucker and Lewis's Reliability Coefficient = 0.5196965955


Initial Factor Method: Maximum Likelihood

                      Squared Canonical Correlations

                              FACTOR1   FACTOR2
                             1.000000  0.951887

          Eigenvalues of the Weighted Reduced Correlation Matrix:
                  Total = 19.7845481  Average = 4.94613703

                        1           2           3           4           5
 Eigenvalue         .         19.7845      0.5431     -0.0398     -0.5033
 Difference         .         19.2414      0.5829      0.4636
 Proportion         .          1.0000      0.0275     -0.0020     -0.0254
 Cumulative         .          1.0000      1.0275      1.0254      1.0000


Initial Factor Method: Maximum Likelihood

                              Factor Pattern

                                  FACTOR1    FACTOR2
                       Y1         1.00000*   0.00000   total population
                       Y2         0.00975    0.90003*  median school years
                       Y3         0.97245*   0.11797   total employment
                       Y4         0.43887    0.78930*  misc. profess services
                       Y5         0.02241    0.95989*  median value house

                     Variance explained by each factor

                                   FACTOR1   FACTOR2
                      Weighted   24.435550 19.784547
                      Unweighted  2.138863  2.368350


Initial Factor Method: Maximum Likelihood

             Final Communality Estimates and Variable Weights
      Total Communality: Weighted = 44.220097   Unweighted = 4.507214

                          Y1        Y2        Y3        Y4        Y5
      Communality   1.000000  0.810150  0.959576  0.815599  0.921888
      Weight         .        5.268444 24.727338  5.425519 12.798798


Prerotation Method: Varimax

                     Orthogonal Transformation Matrix

                                     1         2
                           1      0.02133   0.99977
                           2      0.99977  -0.02133

                          Rotated Factor Pattern

                                  FACTOR1    FACTOR2
                       Y1         0.02133    0.99977*  total population
                       Y2         0.90003*  -0.00945   median school years
                       Y3         0.13869    0.96971*  total employment
                       Y4         0.79848*   0.42193   misc. profess services
                       Y5         0.96015*   0.00193   median value house


Prerotation Method: Varimax

                     Variance explained by each factor

                                   FACTOR1   FACTOR2
                      Weighted   20.001570 24.218527
                      Unweighted  2.389209  2.118004

             Final Communality Estimates and Variable Weights
      Total Communality: Weighted = 44.220097   Unweighted = 4.507214

                          Y1        Y2        Y3        Y4        Y5
      Communality   1.000000  0.810150  0.959576  0.815599  0.921888
      Weight         .        5.268444 24.727338  5.425519 12.798798


Rotation Method: Promax

               Target Matrix for Procrustean Transformation

                                  FACTOR1   FACTOR2
                       Y1         0.00001   1.00000
                       Y2         0.99984  -0.00000
                       Y3         0.00284   0.97075
                       Y4         0.69117   0.10205
                       Y5         1.00000   0.00000

                     Procrustean Transformation Matrix

                                     1         2

                           1      1.03022  -0.09567
                           2     -0.10099   0.95877


Rotation Method: Promax

                 Normalized Oblique Transformation Matrix

                                     1         2

                           1     -0.07781   1.01233
                           2      1.01678  -0.12288

                         Inter-factor Correlations

                                  FACTOR1   FACTOR2
                       FACTOR1    1.00000   0.19589
                       FACTOR2    0.19589   1.00000


Rotation Method: Promax

                  Rotated Factor Pattern (Std Reg Coefs)

                                  FACTOR1    FACTOR2
                       Y1        -0.07781    1.01233*  total population
                       Y2         0.91438*  -0.10072   median school years
                       Y3         0.04428    0.96994*  total employment
                       Y4         0.76840*   0.34729   misc. profess services
                       Y5         0.97426*  -0.09526   median value house

                        Reference Axis Correlations

                                  FACTOR1   FACTOR2
                       FACTOR1    1.00000  -0.19589
                       FACTOR2   -0.19589   1.00000


Rotation Method: Promax

              Reference Structure (Semipartial Correlations)

                                  FACTOR1   FACTOR2
                       Y1        -0.07630   0.99271
                       Y2         0.89666  -0.09877
                       Y3         0.04343   0.95115
                       Y4         0.75351   0.34056
                       Y5         0.95538  -0.09342

        Variance explained by each factor eliminating other factors

                                   FACTOR1   FACTOR2
                      Weighted   19.045100 23.162829
                      Unweighted  2.292243  2.024633


Rotation Method: Promax

                      Factor Structure (Correlations)

                                  FACTOR1    FACTOR2
                       Y1         0.12050    0.99708*  total population
                       Y2         0.89465*   0.07840   median school years
                       Y3         0.23429    0.97862*  total employment
                       Y4         0.83643*   0.49782   misc. profess services
                       Y5         0.95559*   0.09559   median value house

         Variance explained by each factor ignoring other factors

                                   FACTOR1   FACTOR2
                      Weighted   21.057268 25.174997
                      Unweighted  2.482581  2.214971


Rotation Method: Promax

             Final Communality Estimates and Variable Weights
      Total Communality: Weighted = 44.220097   Unweighted = 4.507214

                          Y1        Y2        Y3        Y4        Y5
      Communality   1.000000  0.810150  0.959576  0.815599  0.921888
      Weight         .        5.268444 24.727338  5.425519 12.798798