Hello, Mr Hammer,
Promax is an olique rotation method, i.e. the factors can be correlated
after rotation. Then loadings of items on factors and correlations of
items with factors are different from each other. Hence, there are two
matrices of coefficients: the structure matrix, i.e. the matrix of
correlations of items with factors, and the pattern matrix, i.e. the
matrix of loadings of items on factors. With uncorrelated factors both
matrices are the same and only one of them has to be printed.
The sum of squared loadings is not meaningful with correlated factors.
With uncorrelated factors the sum of squared loadings of a factor
indicates the proportion of variance explained by a factor, but not with
correlated factors.
Kind regards,
Dr. Oliver Walter
Am 13.04.2024 um 22:20 schrieb Andreas Hammer:
Hello,
The manual specifies Promax as a rotation method for the factor
analysis. I cannot call up this method via the menu. If I enter it via
the syntax, a factor analysis can be run - but in my dataset:
1) the sum of squared loadings is not calculated,
2) instead of a rotated matrix I get a "pattern matrix
(Mustermatrix)". Maybe it's the same?
With Varimax there is no problem.
What have I overlooked?
Thank you.
Kind regards
Andreas Hammer
Systeminformation
╭────────────────────────┬──────────────────────────────────╮
│Version │GNU pspp 2.0.0-g4c33fd │
│Hostsystem │x86_64-w64-mingw32 │
│Build System │x86_64-pc-linux-gnu │
│Lokale Sprachverzeichnis│C:\Program Files\PSPP/share/locale│
│Compilerversion │10-win32 20210110 │
╰────────────────────────┴──────────────────────────────────╯
I use win 11.
---------------------------------
Syntax like this:
FACTOR
/VARIABLES= WW02_29 WW02_02 WW02_03 WW02_30 [and more items,
totaly 64]
/CRITERIA = MINEIGEN (1) ITERATE (25)
/EXTRACTION =PAF
/METHOD = CORRELATION
/PLOT = EIGEN
/PRINT = INITIAL EXTRACTION ROTATION SIG AIC KMO
/CRITERIA = ITERATE (25)
/ROTATION = VARIMAX.
