The rotation tag has no wiki summary.
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0answers
43 views
Procrustes Analysis of 3d point cloud without defined landmarks
I am working with several hundred 3d point clouds generated using a 3d scanner and would like to be able to compare their shapes using something like a procrustes analysis. Instead of manually ...
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vote
1answer
45 views
How to output varimax-rotated data in R?
I have ran PCA on 25 variables and selected the top 7 PCs using 'prcomp'.
prc <- prcomp(pollutions, center=T, scale=T)
I have then done varimax rotation on ...
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2answers
30 views
How many PCs should varimax rotation be applied to?
I have a list of 25 air pollutants many of which are strongly correlated. I was hoping to reduce down to a short list of eigenvectors which would each be composed of a small number of the pollutants.
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2
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1answer
50 views
A textbook error w.r.t structure and pattern loadings
I have this picture in Lattin representing structure and pattern loadings in factor analysis. If $Z$ (an observed variable) $=w_1 F_1+w_2 F_2$ (according to factor model), then the pattern loadings of ...
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1answer
91 views
To rotate or not to rotate post-PCA and pre-cluster analysis
Questions in respect to rotation post-PCA have been answered before -> its all in the hands of the researcher... Same answer to the question if rotation (orthogonal or not) makes sense before plugging ...
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1answer
1k views
Exploratory factor analysis - promax & factor cross-loadings
I have a question regarding the best practice for dealing with cross-loadings on factors after conducting an exploratory factor analysis using a promax rotation. Just to give a bit of background ...
3
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1answer
231 views
Is it acceptable to rotate factors with PCA for binary data?
What issues, if any, might there be in rotating factors in order to obtain factor/component loadings of binary data? Is it acceptable to rotate the factors when doing a traditional PCA? (Assuming I’m ...
2
votes
1answer
869 views
Can I somehow compute variance explained by PC after Oblique rotation in PCA?
Let´s say that my PCA analysis extracted 2 components, which explain 80% of the variance before rotation. The components were then rotated using oblique (Direct Oblimin) rotation, so SPSS cannot ...
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0answers
174 views
How is the proof that the Quartimax/Varimax-rotation converges?
Empirically the quartimax-/varimax-rotation has proven useful and it was always converging in my applications. But from my readings years ago I have a vague remembering, that the fact of a proof of ...
3
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1answer
203 views
Detecting reflection in non-orthogonal rotation
I've known that, in orthogonal rotation, if the rotation matrix has determinant of -1 then reflection is present. Otherwise the determinant is +1 and we have pure rotation. May I extend this ...
3
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2answers
200 views
Rotation matrices and prior invariance for arbitrary dimensions
I have a question about a rotation matrix, which can be represented in 2 dimensions as:
$$R_{2}(\theta)=\begin{bmatrix} \cos\theta & \sin\theta \\ -\sin\theta & \cos\theta \end{bmatrix}$$
For ...
